Programs & Examples On #External url

Anything related to external Uniform Resource Locators (URLS), i.e. URLs pointing to resources external to the website where the URLs appears.

Doing HTTP requests FROM Laravel to an external API

We can use package Guzzle in Laravel, it is a PHP HTTP client to send HTTP requests.

You can install Guzzle through composer

composer require guzzlehttp/guzzle:~6.0

Or you can specify Guzzle as a dependency in your project's existing composer.json

{
   "require": {
      "guzzlehttp/guzzle": "~6.0"
   }
}

Example code in laravel 5 using Guzzle as shown below,

use GuzzleHttp\Client;
class yourController extends Controller {

    public function saveApiData()
    {
        $client = new Client();
        $res = $client->request('POST', 'https://url_to_the_api', [
            'form_params' => [
                'client_id' => 'test_id',
                'secret' => 'test_secret',
            ]
        ]);
        echo $res->getStatusCode();
        // 200
        echo $res->getHeader('content-type');
        // 'application/json; charset=utf8'
        echo $res->getBody();
        // {"type":"User"...'
}

Changing image on hover with CSS/HTML

_x000D_
_x000D_
.hover_image:hover {text-decoration: none} /* Optional (avoid undesired underscore if a is used as wrapper) */_x000D_
.hide {display:none}_x000D_
/* Do the shift: */_x000D_
.hover_image:hover img:first-child{display:none}_x000D_
.hover_image:hover img:last-child{display:inline-block}
_x000D_
<body> _x000D_
    <a class="hover_image" href="#">_x000D_
        <!-- path/to/first/visible/image: -->_x000D_
        <img src="http://farmacias.dariopm.com/cc2/_cc3/images/f1_silverstone_2016.jpg" />_x000D_
        <!-- path/to/hover/visible/image: -->_x000D_
        <img src="http://farmacias.dariopm.com/cc2/_cc3/images/f1_malasia_2016.jpg" class="hide" />_x000D_
    </a>_x000D_
</body>
_x000D_
_x000D_
_x000D_

To try to improve this Rashid's good answer I'm adding some comments:

The trick is done over the wrapper of the image to be swapped (an 'a' tag this time but maybe another) so the 'hover_image' class has been put there.

Advantages:

  • Keeping both images url together in the same place helps if they need to be changed.

  • Seems to work with old navigators too (CSS2 standard).

  • It's self explanatory.

  • The hover image is preloaded (no delay after hovering).

Redis command to get all available keys?

Get All Keys In Redis

Get all keys using the --scan option:

$ redis-cli --scan --pattern '*'

List all keys using the KEYS command:

$ redis-cli KEYS '*'

How can I delete a user in linux when the system says its currently used in a process

First use pkill or kill -9 <pid> to kill the process.

Then use following userdel command to delete user,

userdel -f cafe_fixer

According to userdel man page:

-f, --force

This option forces the removal of the user account, even if the user is still logged in. It also forces userdel to remove the user's home directory and mail spool, even if another user uses the same home directory or if the mail spool is not owned by the specified user. If USERGROUPS_ENAB is defined to yes in /etc/login.defs and if a group exists with the same name as the deleted user, then this group will be removed, even if it is still the primary group of another user.

Edit 1: (by @Ajedi32)

Note: This option (i.e. --force) is dangerous and may leave your system in an inconsistent state.

Edit 2: (by @socketpair)

In spite of the description about some files, this key allows removing the user while it is in use. Don't forget to chdir / before, because this command will also remove home directory.

How to hide reference counts in VS2013?

Another option is to use mouse, right click on "x reference". Context menu "CodeLens Options" will appear, saving all the navigation headache.

How to check if a char is equal to an empty space?

You could use

Character.isWhitespace(c)

or any of the other available methods in the Character class.

  if (c == ' ')

also works.

PHP Regex to check date is in YYYY-MM-DD format

If it is of any help, here is a regex for j-n-Y format (year has to be greater than 2018):

if (preg_match('/^([1-9]|[1-2][0-9]|[3][0-1])\-([1-9]|[1][0-2])\-(?:20)([1][8-9]|[2-9][0-9])$/', $date)) {
   // Do stuff
}

navbar color in Twitter Bootstrap

An excellent resource to see how to theme bootstrap is: bootswatch.com. It has nice examples and shows code as well. In short, they use lessc to recompile the bootstrap.css to your new color-theme.css. The nice thing of their approach is that is build on top of bootstrap, so when bootstrap is updated, you just recompile.

Links about using lessc and bootstrap:

Vue.js - How to properly watch for nested data

Personally I prefer this clean implementation:

watch: {
  myVariable: {
     handler(newVal, oldVal){  // here having access to the new and old value
       // do stuff
     },
     deep: true,
     immediate: true //  Also very important the immediate in case you need it, the callback will be called immediately after the start of the observation

  }
}

WPF Check box: Check changed handling

What about the Checked event? Combine that with AttachedCommandBehaviors or something similar, and a DelegateCommand to get a function fired in your viewmodel everytime that event is called.

difference between primary key and unique key

Unique key :- It should be used when you have to give unique value.In the case of unique key it means null values are also allowed.Unique keys are those keys which are unique and non similar in that column like for example your pet name.it can be nothing like null and if you are asking in context of database then it must be noted that every null is different from another null in the database.EXCEPT-SQL Server where null=null is true


primary key :- It should be used when you have to give uniquely identify a row.primary is key which unique for every row in a database constraint is that it doesn't allow null in it.so, you might have seen that the database have a column which is auto increment and it is the primary key of the table. plus it can be used as a foreign key in another table.example can be orderId on a order Table,billId in a bill Table.

now coming back to situation when to use it:-

1) primary key in the column which can not be null in the table and you are using as foreign key in another table for creating relationship

2) unique key in table where it doesn't affect in table or in the whole database whether you take the null for the particular column like snacks in the restaurant it is possible you don't take snacks in a restaurant

Reading value from console, interactively

I've used another API for this purpose..

var readline = require('readline');
var rl = readline.createInterface(process.stdin, process.stdout);
rl.setPrompt('guess> ');
rl.prompt();
rl.on('line', function(line) {
    if (line === "right") rl.close();
    rl.prompt();
}).on('close',function(){
    process.exit(0);
});

This allows to prompt in loop until the answer is right. Also it gives nice little console.You can find the details @ http://nodejs.org/api/readline.html#readline_example_tiny_cli

Why is "throws Exception" necessary when calling a function?

Java requires that you handle or declare all exceptions. If you are not handling an Exception using a try/catch block then it must be declared in the method's signature.

For example:

class throwseg1 {
    void show() throws Exception {
        throw new Exception();
    }
}

Should be written as:

class throwseg1 {
    void show() {
        try {
            throw new Exception();
        } catch(Exception e) {
            // code to handle the exception
        }
    }
}

This way you can get rid of the "throws Exception" declaration in the method declaration.

Allow 2 decimal places in <input type="number">

Try this for allowing only 2 decimal in input type

<input type="number" step="0.01" class="form-control"  />

Or Use jQuery as suggested by @SamohtVII

$( "#ELEMENTID" ).blur(function() {
    this.value = parseFloat(this.value).toFixed(2);
});

Customize UITableView header section

call this delegate method

-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{

return @"Some Title";
}

this will give a chance to automatically add a default header with dynamic title .

You may use reusable and customizable header / footer .

https://github.com/sourov2008/UITableViewCustomHeaderFooterSection

How can I find all *.js file in directory recursively in Linux?

Use find on the command line:

find /my/directory -name '*.js'

Indent multiple lines quickly in vi

:line_num_start,line_num_end>

For example,

14,21> shifts line number 14 to 21 to one tab

Increase the '>' symbol for more tabs.

For example,

14,21>>> for three tabs

What is the meaning of "int(a[::-1])" in Python?

The notation that is used in

a[::-1]

means that for a given string/list/tuple, you can slice the said object using the format

<object_name>[<start_index>, <stop_index>, <step>]

This means that the object is going to slice every "step" index from the given start index, till the stop index (excluding the stop index) and return it to you.

In case the start index or stop index is missing, it takes up the default value as the start index and stop index of the given string/list/tuple. If the step is left blank, then it takes the default value of 1 i.e it goes through each index.

So,

a = '1234'
print a[::2]

would print

13

Now the indexing here and also the step count, support negative numbers. So, if you give a -1 index, it translates to len(a)-1 index. And if you give -x as the step count, then it would step every x'th value from the start index, till the stop index in the reverse direction. For example

a = '1234'
print a[3:0:-1]

This would return

432

Note, that it doesn't return 4321 because, the stop index is not included.

Now in your case,

str(int(a[::-1]))

would just reverse a given integer, that is stored in a string, and then convert it back to a string

i.e "1234" -> "4321" -> 4321 -> "4321"

If what you are trying to do is just reverse the given string, then simply a[::-1] would work .

How to programmatically take a screenshot on Android?

You can try the following library: http://code.google.com/p/android-screenshot-library/ Android Screenshot Library (ASL) enables to programmatically capture screenshots from Android devices without requirement of having root access privileges. Instead, ASL utilizes a native service running in the background, started via the Android Debug Bridge (ADB) once per device boot.

How to change Hash values?

There's a method for that in ActiveSupport v4.2.0. It's called transform_values and basically just executes a block for each key-value-pair.

Since they're doing it with a each I think there's no better way than to loop through.

hash = {sample: 'gach'}

result = {}
hash.each do |key, value|
  result[key] = do_stuff(value)
end

Update:

Since Ruby 2.4.0 you can natively use #transform_values and #transform_values!.

How to check the gradle version in Android Studio?

File->Project Structure->Project pane->"Android plugin version".

Make sure you don't confuse the Gradle version with the Android plugin version. The former is the build system itself, the latter is the plugin to the build system that knows how to build Android projects

When to use SELECT ... FOR UPDATE?

The only portable way to achieve consistency between rooms and tags and making sure rooms are never returned after they had been deleted is locking them with SELECT FOR UPDATE.

However in some systems locking is a side effect of concurrency control, and you achieve the same results without specifying FOR UPDATE explicitly.


To solve this problem, Thread 1 should SELECT id FROM rooms FOR UPDATE, thereby preventing Thread 2 from deleting from rooms until Thread 1 is done. Is that correct?

This depends on the concurrency control your database system is using.

  • MyISAM in MySQL (and several other old systems) does lock the whole table for the duration of a query.

  • In SQL Server, SELECT queries place shared locks on the records / pages / tables they have examined, while DML queries place update locks (which later get promoted to exclusive or demoted to shared locks). Exclusive locks are incompatible with shared locks, so either SELECT or DELETE query will lock until another session commits.

  • In databases which use MVCC (like Oracle, PostgreSQL, MySQL with InnoDB), a DML query creates a copy of the record (in one or another way) and generally readers do not block writers and vice versa. For these databases, a SELECT FOR UPDATE would come handy: it would lock either SELECT or the DELETE query until another session commits, just as SQL Server does.

When should one use REPEATABLE_READ transaction isolation versus READ_COMMITTED with SELECT ... FOR UPDATE?

Generally, REPEATABLE READ does not forbid phantom rows (rows that appeared or disappeared in another transaction, rather than being modified)

  • In Oracle and earlier PostgreSQL versions, REPEATABLE READ is actually a synonym for SERIALIZABLE. Basically, this means that the transaction does not see changes made after it has started. So in this setup, the last Thread 1 query will return the room as if it has never been deleted (which may or may not be what you wanted). If you don't want to show the rooms after they have been deleted, you should lock the rows with SELECT FOR UPDATE

  • In InnoDB, REPEATABLE READ and SERIALIZABLE are different things: readers in SERIALIZABLE mode set next-key locks on the records they evaluate, effectively preventing the concurrent DML on them. So you don't need a SELECT FOR UPDATE in serializable mode, but do need them in REPEATABLE READ or READ COMMITED.

Note that the standard on isolation modes does prescribe that you don't see certain quirks in your queries but does not define how (with locking or with MVCC or otherwise).

When I say "you don't need SELECT FOR UPDATE" I really should have added "because of side effects of certain database engine implementation".

How to make a text box have rounded corners?

This can be done with CSS3:

<input type="text" />

input
{
  -moz-border-radius: 15px;
 border-radius: 15px;
    border:solid 1px black;
    padding:5px;
}

http://jsfiddle.net/UbSkn/1/


However, an alternative would be to put the input inside a div with a rounded background, and no border on the input

How to get Javascript Select box's selected text

Just use

$('#SelectBoxId option:selected').text(); For Getting text as listed

$('#SelectBoxId').val(); For Getting selected Index value

Saving an image in OpenCV

If you use C++, it is best to use C++ interface:

using namespace cv;
// Capture the Image from the webcam
VideoCapture cap(0);

// Get the frame
Mat save_img; cap >> save_img;

if(save_img.empty())
{
  std::cerr << "Something is wrong with the webcam, could not get frame." << std::endl;
}
// Save the frame into a file
imwrite("test.jpg", save_img); // A JPG FILE IS BEING SAVED

Best data type to store money values in MySQL

Storing money as BIGINT multiplied by 100 or more with the reason to use less storage space makes no sense in all "normal" situations.

How to extract IP Address in Spring MVC Controller get call?

You can get the IP address statically from the RequestContextHolder as below :

HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes())
        .getRequest();

String ip = request.getRemoteAddr();

Deserializing JSON Object Array with Json.net

For those who don't want to create any models, use the following code:

var result = JsonConvert.DeserializeObject<
  List<Dictionary<string, 
    Dictionary<string, string>>>>(content);

Note: This doesn't work for your JSON string. This is not a general solution for any JSON structure.

JavaScript blob filename without link

The only way I'm aware of is the trick used by FileSaver.js:

  1. Create a hidden <a> tag.
  2. Set its href attribute to the blob's URL.
  3. Set its download attribute to the filename.
  4. Click on the <a> tag.

Here is a simplified example (jsfiddle):

var saveData = (function () {
    var a = document.createElement("a");
    document.body.appendChild(a);
    a.style = "display: none";
    return function (data, fileName) {
        var json = JSON.stringify(data),
            blob = new Blob([json], {type: "octet/stream"}),
            url = window.URL.createObjectURL(blob);
        a.href = url;
        a.download = fileName;
        a.click();
        window.URL.revokeObjectURL(url);
    };
}());

var data = { x: 42, s: "hello, world", d: new Date() },
    fileName = "my-download.json";

saveData(data, fileName);

I wrote this example just to illustrate the idea, in production code use FileSaver.js instead.

Notes

  • Older browsers don't support the "download" attribute, since it's part of HTML5.
  • Some file formats are considered insecure by the browser and the download fails. Saving JSON files with txt extension works for me.

pip not working in Python Installation in Windows 10

I faced a problem upgrading pip from version 9.0.1 to 9.0.3 The upgrade failed middle way(after uninstalling version 9.0.1 and without installing version 9.0.3). This usually creates a broken pip file. Broken pip can be solved by the command-->

easy_install pip

Which usually installs the latest version of pip, and solves the issue. In order to confirm, type

pip --version

Hope this was helpfull...

Is it possible to run an .exe or .bat file on 'onclick' in HTML

You can do it on Internet explorer with OCX component and on chrome browser using a chrome extension chrome document in any case need additional settings on the client system!

Important part of chrome extension source:

var port = chrome.runtime.connectNative("your.app.id"); 
      port.onMessage.addListener(onNativeMessage); 
      port.onDisconnect.addListener(onDisconnected);
      port.postMessage("send some data to STDIO");

permission file:

{
      "name": "your.app.id",
      "description": "Name of your extension",
      "path": "myapp.exe",
      "type": "stdio",
      "allowed_origins": [
            "chrome-extension://IDOFYOUREXTENSION_lokldaeplkmh/"
      ]
}

and windows registry settings:

HKEY_CURRENT_USER\Software\Google\Chrome\NativeMessagingHosts\your.app.id
REG_EXPAND_SZ : c:\permissionsettings.json

/usr/bin/ld: cannot find

When you make the call to gcc it should say

g++ -Wall -I/home/alwin/Development/Calculator/ -L/opt/lib main.cpp -lcalc -o calculator

not -libcalc.so 

I have a similar problem with auto-generated makes.

You can create a soft link from your compile directory to the library directory. Then the library becomes "local".

cd /compile/directory

ln -s  /path/to/libcalc.so libcalc.so

Pass Model To Controller using Jquery/Ajax

//C# class

public class DashBoardViewModel 
{
    public int Id { get; set;} 
    public decimal TotalSales { get; set;} 
    public string Url { get; set;} 
     public string MyDate{ get; set;} 
}

//JavaScript file
//Create dashboard.js file
$(document).ready(function () {

    // See the html on the View below
    $('.dashboardUrl').on('click', function(){
        var url = $(this).attr("href"); 
    });

    $("#inpDateCompleted").change(function () {   

        // Construct your view model to send to the controller
        // Pass viewModel to ajax function 

        // Date
        var myDate = $('.myDate').val();

        // IF YOU USE @Html.EditorFor(), the myDate is as below
        var myDate = $('#MyDate').val();
        var viewModel = { Id : 1, TotalSales: 50, Url: url, MyDate: myDate };


        $.ajax({
            type: 'GET',
            dataType: 'json',
            cache: false,
            url: '/Dashboard/IndexPartial',
            data: viewModel ,
            success: function (data, textStatus, jqXHR) {
                //Do Stuff 
                $("#DailyInvoiceItems").html(data.Id);
            },
            error: function (jqXHR, textStatus, errorThrown) {
                //Do Stuff or Nothing
            }
        });

    });
});

//ASP.NET 5 MVC 6 Controller
public class DashboardController {

    [HttpGet]
    public IActionResult IndexPartial(DashBoardViewModel viewModel )
    {
        // Do stuff with my model
        var model = new DashBoardViewModel {  Id = 23 /* Some more results here*/ };
        return Json(model);
    }
}

// MVC View 
// Include jQuerylibrary
// Include dashboard.js 
<script src="~/Scripts/jquery-2.1.3.js"></script>
<script src="~/Scripts/dashboard.js"></script>
// If you want to capture your URL dynamically 

<div>
    <a class="dashboardUrl" href ="@Url.Action("IndexPartial","Dashboard")"> LinkText </a>
</div>
<div>
    <input class="myDate" type="text"/>
//OR
   @Html.EditorFor(model => model.MyDate) 
</div>

What's the difference between ISO 8601 and RFC 3339 Date Formats?

There are lots of differences between ISO 8601 and RFC 3339. Here is some examples to give you an idea:

2020-12-09T16:09:53+00:00 is a date time value that is compliant both both standards.

2020-12-09 16:09:53+00:00 uses a space to separate the date and time. This is allowed by RFC 3339 but not allowed by ISO 8601.

2020-12-09T16:09:53-00:00 has a negative sign in the time offset. This is allowed by RFC 3339 but not allowed by ISO 8601.

20201209T160953Z omits the hyphens. This is allowed by ISO 8601 but not allowed by RFC 3339.

ISO 8601 allows for things like ordinal dates such as 2020-344 which represents the 344th day of year 2020. RFC 3339 doesn't allow for that.

For your questions:

Is one just an extension?

No. As shown above each standard supports syntax variations not supported by the the other standard. So one syntax is not a superset or an extension of the other.

Should I use one over the other?

Of course this depends on your scenario. A safe general strategy is to generate date time strings that are valid by both standards.

Another good general strategy is to use an existing standard library for parsing/formatting date time strings and not write custom implementations unless you are addressing a genuinely custom scenario.

Do I really need to care that bad?

Well, that's up to you. Most regular developers who deal with date time strings should have a high level understanding but don't need to dive into the details.

PHP how to get value from array if key is in a variable

$value = ( array_key_exists($key, $array) && !empty($array[$key]) ) 
         ? $array[$key] 
         : 'non-existant or empty value key';

Delete commit on gitlab

Supose you have the following scenario:

* 1bd2200 (HEAD, master) another commit
* d258546 bad commit
* 0f1efa9 3rd commit
* bd8aa13 2nd commit
* 34c4f95 1st commit

Where you want to remove d258546 i.e. "bad commit".

You shall try an interactive rebase to remove it: git rebase -i 34c4f95

then your default editor will pop with something like this:

 pick bd8aa13 2nd commit
 pick 0f1efa9 3rd commit
 pick d258546 bad commit
 pick 1bd2200 another commit

 # Rebase 34c4f95..1bd2200 onto 34c4f95
 #
 # Commands:
 #  p, pick = use commit
 #  r, reword = use commit, but edit the commit message
 #  e, edit = use commit, but stop for amending
 #  s, squash = use commit, but meld into previous commit
 #  f, fixup = like "squash", but discard this commit's log message
 #  x, exec = run command (the rest of the line) using shell
 #
 # These lines can be re-ordered; they are executed from top to bottom.
 #
 # If you remove a line here THAT COMMIT WILL BE LOST.
 #
 # However, if you remove everything, the rebase will be aborted.
 #
 # Note that empty commits are commented out

just remove the line with the commit you want to strip and save+exit the editor:

 pick bd8aa13 2nd commit
 pick 0f1efa9 3rd commit
 pick 1bd2200 another commit
 ...

git will proceed to remove this commit from your history leaving something like this (mind the hash change in the commits descendant from the removed commit):

 * 34fa994 (HEAD, master) another commit
 * 0f1efa9 3rd commit
 * bd8aa13 2nd commit
 * 34c4f95 1st commit

Now, since I suppose that you already pushed the bad commit to gitlab, you'll need to repush your graph to the repository (but with the -f option to prevent it from being rejected due to a non fastforwardeable history i.e. git push -f <your remote> <your branch>)

Please be extra careful and make sure that none coworker is already using the history containing the "bad commit" in their branches.

Alternative option:

Instead of rewrite the history, you may simply create a new commit which negates the changes introduced by your bad commit, to do this just type git revert <your bad commit hash>. This option is maybe not as clean, but is far more safe (in case you are not fully aware of what are you doing with an interactive rebase).

HtmlSpecialChars equivalent in Javascript?

Reversed one:

function decodeHtml(text) {
    return text
        .replace(/&amp;/g, '&')
        .replace(/&lt;/ , '<')
        .replace(/&gt;/, '>')
        .replace(/&quot;/g,'"')
        .replace(/&#039;/g,"'");
}

What do I need to do to get Internet Explorer 8 to accept a self signed certificate?

This may help someone I am on IE11 windows 7 and what I did In addition to install the certificate is Going to internet options ==> advance tab == > security ==> "remove the check " from warn about certificate address mismatch in addition to below - dont forget to close All IE instances and restart- after finishing :

1-Start Internet Explorer running .

2-Browse to server computer using the computer name (ignore certificate warnings)

3-Click the ”Certificate Error” text in the top of the screen and select ”View certificates”

4-In the Certificate dialog, click Install Certificate -> Next

5-Select Place all certificates in the following store -> Browse

6-Install to the trusted root Certification ..

then restart .

Hope this help someone .

Replacing last character in a String with java

You can simply use :

if(fieldName.endsWith(","))
{
   StringUtils.chop(fieldName);
}

from commons-lang

Is there a Public FTP server to test upload and download?

There's lots of FTP sites you can get into with the 'anonymous' account and download, but a 'public' site that allows anonymous uploads would be utterly swamped with pr0n and warez in short order.

It's easy enough to set up your own FTP server for testing uploads. There's plenty of them for most any desktop OS. There's one built into IIS, for instance.

How do I attach events to dynamic HTML elements with jQuery?

You can bind a single click event to a page for all elements, no matter if they are already on that page or if they will arrive at some future time, like that:

$(document).bind('click', function (e) {
   var target = $(e.target);
   if (target.is('.myclass')) {
      e.preventDefault(); // if you want to cancel the event flow
      // do something
   } else if (target.is('.myotherclass')) {
      e.preventDefault();
      // do something else
   }
});

Been using it for a while. Works like a charm.

In jQuery 1.7 and later, it is recommended to use .on() in place of bind or any other event delegation method, but .bind() still works.

How to bind event listener for rendered elements in Angular 2?

@HostListener('window:click', ['$event']) onClick(event){ }

check this below link to detect CapsLock on click, keyup and keydown on current window. No need to add any event in html doc

Detect and warn users about caps lock is on

How to "z-index" to make a menu always on top of the content

You most probably don't need z-index to do that. You can use relative and absolute positioning.

I advise you to take a better look at css positioning and the difference between relative and absolute positioning... I saw you're setting position: absolute; to an element and trying to float that element. It won't work friend! When you understand positioning in CSS it will make your work a lot easier! ;)

Edit: Just to be clear, positioning is not a replacement for them and I do use z-index. I just try to avoid using them. Using z-indexes everywhere seems easy and fun at first... until you have bugs related to them and find yourself having to revisit and manage z-indexes.

Illegal Character when trying to compile java code

  1. If using an IDE, specify the java file encoding (via the properties panel)
  2. If NOT using an IDE, use an advanced text-editor (I can recommend Notepad++) and set the encoding to "UTF without BOM", or "ANSI", if that suits you.

Makefile If-Then Else and Loops

Have you tried the GNU make documentation? It has a whole section about conditionals with examples.

How to margin the body of the page (html)?

Yeah a CSS primer will not hurt here so you can do two things: 1 - within the tags of your html you can open a style tag like this:

<style type="text/css">
  body {
   margin: 0px;
  }
  /*
   * this is the same as writing
   * body { margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;}
   * I'm adding px here for clarity sake but the unit is not really needed if you have 0
   * look into em, pt and % for other unit types 
   * the rules are always clockwise: top, right, bottom, left
  */
</style>

2- the above though will only work on the page you have this code embeded, so if if you wanted to reuse this in 10 files, then you will have to copy it over on all 10 files, and if you wanted to make a change let's say have a margin of 5px instead, you would have to open all those files and make the edit. That's why using an external style sheet is a golden rule in front end coding. So save the body declaration in a separate file named style.css for example and from your add this to your html instead:

<link rel="stylesheet" type="text/css" href="style.css"/>

Now you can put this in the of all pages that will benefit from these styles and whenever needed to change them you will only need to do so in one place. Hope it helps. Cheers

Maven Unable to locate the Javac Compiler in:

I tried all of the above suggestions, which did not work for me, but I found how to fix the error in my case.

The following steps made the project compile succesfully:

In project explorer, right-click on project, select “properties” In the tree on the right, go to Java build path. Select the tab “libraries”. Click “Add library”. Select JRE system library. Click next. Select radio button Alternate JRE. Click “installed JRE’s”. Select the JRE with the right version. Click Appy and close. In the next screen, click finish. In the properties window, click Apply and close. In the project explorer, right-click your pom.xml and select run as > maven build In the goal textbox, write “install”. Click Run.

This made the project build succesfully in my case.

Error "gnu/stubs-32.h: No such file or directory" while compiling Nachos source code

From the GNU UPC website:

Compiler build fails with fatal error: gnu/stubs-32.h: No such file or directory

This error message shows up on the 64 bit systems where GCC/UPC multilib feature is enabled, and it indicates that 32 bit version of libc is not installed. There are two ways to correct this problem:

  • Install 32 bit version of glibc (e.g. glibc-devel.i686 on Fedora, CentOS, ..)
  • Disable 'multilib' build by supplying "--disable-multilib" switch on the compiler configuration command

Adding a 'share by email' link to website

Easiest: http://www.addthis.com/

Best? Well. probably not, But If you don't want to design something bespoke this is the best there is...

SQL LIKE condition to check for integer?

Tested on PostgreSQL 9.5 :

-- only digits

select * from books where title ~ '^[0-9]*$';

or,

select * from books where title SIMILAR TO '[0-9]*';

-- start with digit

select * from books where title ~ '^[0-9]+';

Failed to load the JNI shared Library (JDK)

And for PDT users - avoid the Zend download page - it doesn't have any 64-bit downloads linked.

Use the Elipse site itself.

The above link had an older 3.6 Eclipse which then failed to update itself due to Eclipse Bug #317785.

My solution was to just install 32-bit Java alongside 64-bit - this allowed the Zend installer to work.

It's depressing that amount of Java / Eclipse cruft one has to go through to get a PHP IDE.

Useful example of a shutdown hook in Java?

Shutdown Hooks are unstarted threads that are registered with Runtime.addShutdownHook().JVM does not give any guarantee on the order in which shutdown hooks are started.For more info refer http://techno-terminal.blogspot.in/2015/08/shutdown-hooks.html

Convert negative data into positive data in SQL Server

UPDATE mytbl
SET a = ABS(a)
where a < 0

How do check if a parameter is empty or null in Sql Server stored procedure in IF statement?

that is the right behavior.

if you set @item1 to a value the below expression will be true

IF (@item1 IS NOT NULL) OR (LEN(@item1) > 0)

Anyway in SQL Server there is not a such function but you can create your own:

CREATE FUNCTION dbo.IsNullOrEmpty(@x varchar(max)) returns bit as
BEGIN
IF @SomeVarcharParm IS NOT NULL AND LEN(@SomeVarcharParm) > 0
    RETURN 0
ELSE
    RETURN 1
END

Multi-Line Comments in Ruby?

  def idle
    <<~aid
    This is some description of what idle does.

    It does nothing actually, it's just here to show an example of multiline
    documentation. Thus said, this is something that is more common in the
    python community. That's an important point as it's good to also fit the
    expectation of your community of work. Now, if you agree with your team to
    go with a solution like this one for documenting your own base code, that's
    fine: just discuss about it with them first.

    Depending on your editor configuration, it won't be colored like a comment,
    like those starting with a "#". But as any keyword can be used for wrapping
    an heredoc, it is easy to spot anyway. One could even come with separated
    words for different puposes, so selective extraction for different types of
    documentation generation would be more practical. Depending on your editor,
    you possibly could configure it to use the same syntax highlight used for
    monoline comment when the keyword is one like aid or whatever you like.

    Also note that the squiggly-heredoc, using "~", allow to position
    the closing term with a level of indentation. That avoids to break the visual reading flow, unlike this far too long line.
    aid
  end

Note that at the moment of the post, the stackoverflow engine doesn't render syntax coloration correctly. Testing how it renders in your editor of choice is let as an exercise. ;)

SQL Error: ORA-12899: value too large for column

example : 1 and 2 table is available

1 table delete entry and select nor 2 table records and insert to no 1 table . when delete time no 1 table dont have second table records example emp id not available means this errors appeared

JavaScript: Parsing a string Boolean value?

Personally I think it's not good, that your function "hides" invalid values as false and - depending on your use cases - doesn't return true for "1".

Another problem could be that it barfs on anything that's not a string.

I would use something like this:

function parseBool(value) {
  if (typeof value === "string") {
     value = value.replace(/^\s+|\s+$/g, "").toLowerCase();
     if (value === "true" || value === "false")
       return value === "true";
  }
  return; // returns undefined
}

And depending on the use cases extend it to distinguish between "0" and "1".

(Maybe there is a way to compare only once against "true", but I couldn't think of something right now.)

How to pass a querystring or route parameter to AWS Lambda from Amazon API Gateway

My goal was to pass a query string similar to:

 protodb?sql=select * from protodb.prototab

to a Node.js 12 Lambda function via a URL from the API gateway. I tried a number of the ideas from the other answers but really wanted to do something in the most API gateway UI native way possible, so I came up with this that worked for me (as of the UI for API Gateway as of December 2020):

On the API Gateway console for a given API, under resources, select the get method. Then select its Integration Request and fill out the data for the lambda function at the top of the page.

Scroll to the bottom and open up the mapping templates section. Choose Request Body Passthrough when there are no templates defined (recommended).

Click on Add mapping templates and create one with the content-type of application/json and hit the check mark button.

For that mapping template, choose the Method Request passthrough on the drop down list for generate template which will fill the textbox under it with AWS' general way to pass everything.

Hit the save button.

Now when I tested it, I could not get the parameter to come through as event.sql under node JS in the Lambda function. It turns out that when the API gateway sends the URL sql query parameter to the Lambda function, it comes through for Node.js as:

 var insql = event.params.querystring.sql;

So the trick that took some time for me was to use JSON.stringify to show the full event stack and then work my way down through the sections to be able to pull out the sql parameter from the query string.

So basically you can use the default passthrough functionality in the API gateway with the trick being how the parameters are passed when you are in the Lambda function.

Rounding to two decimal places in Python 2.7?

You can use str.format(), too:

>>> print "financial return of outcome 1 = {:.2f}".format(1.23456)
financial return of outcome 1 = 1.23

Programmatically register a broadcast receiver

Create a broadcast receiver

[BroadcastReceiver(Enabled = true, Exported = false)]

public class BCReceiver : BroadcastReceiver
{

    BCReceiver receiver;

    public override void OnReceive(Context context, Intent intent)
    {
        //Do something here
    }
}

From your activity add this code:

LocalBroadcastManager.getInstance(ApplicationContext)
    .registerReceiver(receiver, filter);

Where do I find the bashrc file on Mac?

The .bashrc file is in your home directory.

So from command line do:

cd
ls -a

This will show all the hidden files in your home directory. "cd" will get you home and ls -a will "list all".

In general when you see ~/ the tilda slash refers to your home directory. So ~/.bashrc is your home directory with the .bashrc file.

And the standard path to homebrew is in /usr/local/ so if you:

cd /usr/local
ls | grep -i homebrew

you should see the homebrew directory (/usr/local/homebrew). Source

Yes sometimes you may have to create this file and the typical format of a .bashrc file is:

# .bashrc

# User specific aliases and functions
. .alias
alias ducks='du -cks * | sort -rn | head -15'

# Source global definitions
if [ -f /etc/bashrc ]; then
    . /etc/bashrc
fi

PATH=$PATH:/home/username/bin:/usr/local/homebrew
export PATH

If you create your own .bashrc file make sure that the following line is in your ~/.bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi

Getting a union of two arrays in JavaScript

If you use the library underscore you can write like this

_x000D_
_x000D_
var unionArr = _.union([34,35,45,48,49], [48,55]);_x000D_
console.log(unionArr);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"></script>
_x000D_
_x000D_
_x000D_

Ref: http://underscorejs.org/#union

How to sign in kubernetes dashboard?

TL;DR

To get the token in a single oneliner:

kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | awk '/^deployment-controller-token-/{print $1}') | awk '$1=="token:"{print $2}'

This assumes that your ~/.kube/config is present and valid. And also that kubectl config get-contexts indicates that you are using the correct context (cluster and namespace) for the dashboard you are logging into.

Explanation

I derived this answer from what I learned from @silverfox's answer. That is a very informative write up. Unfortunately it falls short of telling you how to actually put the information into practice. Maybe I've been doing DevOps too long, but I think in shell. It's much more difficult for me to learn or teach in English.

Here is that oneliner with line breaks and indents for readability:

kubectl -n kube-system describe secret $(
  kubectl -n kube-system get secret | \
  awk '/^deployment-controller-token-/{print $1}'
) | \
awk '$1=="token:"{print $2}'

There are 4 distinct commands and they get called in this order:

  • Line 2 - This is the first command from @silverfox's Token section.
  • Line 3 - Print only the first field of the line beginning with deployment-controller-token- (which is the pod name)
  • Line 1 - This is the second command from @silverfox's Token section.
  • Line 5 - Print only the second field of the line whose first field is "token:"

How to build a 'release' APK in Android Studio?

AndroidStudio is alpha version for now. So you have to edit gradle build script files by yourself. Add next lines to your build.gradle

android {

    signingConfigs {

        release {

            storeFile file('android.keystore')
            storePassword "pwd"
            keyAlias "alias"
            keyPassword "pwd"
        }
    }

    buildTypes {

       release {

           signingConfig signingConfigs.release
       }
    }
}

To actually run your application at emulator or device run gradle installDebug or gradle installRelease.

You can create helloworld project from AndroidStudio wizard to see what structure of gradle files is needed. Or export gradle files from working eclipse project. Also this series of articles are helpfull http://blog.stylingandroid.com/archives/1872#more-1872

How to lay out Views in RelativeLayout programmatically?

call

tv1.setId(1) 

after

tv1.setText("A");

Switching between GCC and Clang/LLVM using CMake

You definitely don't need to use the various different llvm-ar etc programs:

SET (CMAKE_AR      "/usr/bin/llvm-ar")
SET (CMAKE_LINKER  "/usr/bin/llvm-ld")
SET (CMAKE_NM      "/usr/bin/llvm-nm")
SET (CMAKE_OBJDUMP "/usr/bin/llvm-objdump")
SET (CMAKE_RANLIB  "/usr/bin/llvm-ranlib")

These are made to work on the llvm internal format and as such aren't useful to the build of your application.

As a note -O4 will invoke LTO on your program which you may not want (it will increase compile time greatly) and clang defaults to c99 mode so that flag isn't necessarily needed either.

Activity restart on rotation Android

add this code to your menufests.xml .

this is your activity.

<activity
....
..
android:configChanges="orientation|screenSize"/>

How do I get the number of elements in a list?

The len() function can be used with several different types in Python - both built-in types and library types. For example:

>>> len([1, 2, 3])
3

Email Address Validation for ASP.NET

You can use a RegularExpression validator. The ValidationExpression property has a button you can press in Visual Studio's property's panel that gets lists a lot of useful expressions. The one they use for email addresses is:

\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*

Android intent for playing video?

I have come across this with the Hero, using what I thought was a published API. In the end, I used a test to see if the intent could be received:

private boolean isCallable(Intent intent) {
    List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent, 
        PackageManager.MATCH_DEFAULT_ONLY);
    return list.size() > 0;
}

In use when I would usually just start the activity:

final Intent intent = new Intent("com.android.camera.action.CROP");
intent.setClassName("com.android.camera", "com.android.camera.CropImage");
if (isCallable(intent)) {
    // call the intent as you intended.
} else {
    // make alternative arrangements.
}

obvious: If you go down this route - using non-public APIs - you must absolutely provide a fallback which you know definitely works. It doesn't have to be perfect, it can be a Toast saying that this is unsupported for this handset/device, but you should avoid an uncaught exception. end obvious.


I find the Open Intents Registry of Intents Protocols quite useful, but I haven't found the equivalent of a TCK type list of intents which absolutely must be supported, and examples of what apps do different handsets.

Using .Select and .Where in a single LINQ statement

Did you add the Select() after the Where() or before?

You should add it after, because of the concurrency logic:

 1 Take the entire table  
 2 Filter it accordingly  
 3 Select only the ID's  
 4 Make them distinct.  

If you do a Select first, the Where clause can only contain the ID attribute because all other attributes have already been edited out.

Update: For clarity, this order of operators should work:

db.Items.Where(x=> x.userid == user_ID).Select(x=>x.Id).Distinct();

Probably want to add a .toList() at the end but that's optional :)

How to Resize a Bitmap in Android?

try this this code :

BitmapDrawable drawable = (BitmapDrawable) imgview.getDrawable();
Bitmap bmp = drawable.getBitmap();
Bitmap b = Bitmap.createScaledBitmap(bmp, 120, 120, false);

I hope it's useful.

SQL Server insert if not exists best practice

Ok, this was asked 7 years ago, but I think the best solution here is to forego the new table entirely and just do this as a custom view. That way you're not duplicating data, there's no worry about unique data, and it doesn't touch the actual database structure. Something like this:

CREATE VIEW vw_competitions
  AS
  SELECT
   Id int
   CompetitionName nvarchar(75)
   CompetitionType nvarchar(50)
   OtherField1 int
   OtherField2 nvarchar(64)  --add the fields you want viewed from the Competition table
  FROM Competitions
GO

Other items can be added here like joins on other tables, WHERE clauses, etc. This is most likely the most elegant solution to this problem, as you now can just query the view:

SELECT *
FROM vw_competitions

...and add any WHERE, IN, or EXISTS clauses to the view query.

Shell script "for" loop syntax

Here it worked on Mac OS X.

It includes the example of a BSD date, how to increment and decrement the date also:

for ((i=28; i>=6 ; i--));
do
    dat=`date -v-${i}d -j "+%Y%m%d"` 
    echo $dat
done

Chrome Extension: Make it run every page load

You can put your script into a content-script, see

Contains method for a slice

Not sure generics are needed here. You just need a contract for your desired behavior. Doing the following is no more than what you would have to do in other languages if you wanted your own objects to behave themselves in collections, by overriding Equals() and GetHashCode() for instance.

type Identifiable interface{
    GetIdentity() string
}

func IsIdentical(this Identifiable, that Identifiable) bool{
    return (&this == &that) || (this.GetIdentity() == that.GetIdentity())
}

func contains(s []Identifiable, e Identifiable) bool {
    for _, a := range s {
        if IsIdentical(a,e) {
            return true
        }
    }
    return false
}

How do I convert Int/Decimal to float in C#?

You can just do a cast

int val1 = 1;
float val2 = (float)val1;

or

decimal val3 = 3;
float val4 = (float)val3;

How to decode HTML entities using jQuery?

Suppose you have below String.

Our Deluxe cabins are warm, cozy &amp; comfortable

var str = $("p").text(); // get the text from <p> tag
$('p').html(str).text();  // Now,decode html entities in your variable i.e 

str and assign back to

tag.

that's it.

Pandas aggregate count distinct

'nunique' is an option for .agg() since pandas 0.20.0, so:

df.groupby('date').agg({'duration': 'sum', 'user_id': 'nunique'})

Conversion hex string into ascii in bash command line

Make a script like this:

#!/bin/bash

echo $((0x$1)).$((0x$2)).$((0x$3)).$((0x$4))

Example:

sh converthextoip.sh c0 a8 00 0b

Result:

192.168.0.11

Gcc error: gcc: error trying to exec 'cc1': execvp: No such file or directory

I fixed this problem by explicitly installing g++:

sudo apt-get install g++

Problem was encountered on Ubuntu 12.04 while installing pandas. (Thanks perilbrain.)

HTML anchor tag with Javascript onclick event

Use following code to show menu instead go to href addres

_x000D_
_x000D_
function show_more_menu(e) {_x000D_
  if( !confirm(`Go to ${e.target.href} ?`) ) e.preventDefault();_x000D_
}
_x000D_
<a href='more.php' onclick="show_more_menu(event)"> More >>> </a>
_x000D_
_x000D_
_x000D_

How to create a multiline UITextfield?

Ok I did it with some trick ;) First build a UITextField and increased it's size like this :

CGRect frameRect = textField.frame;
        frameRect.size.height = 53;
        textField.frame = frameRect;

Then build a UITextView exactly in the same area that u made my UITextField, and deleted its background color. Now it looks like that u have a multiple lines TextField !

Pretty-Print JSON in Java

I used org.json built-in methods to pretty-print the data.

JSONObject json = new JSONObject(jsonString); // Convert text to object
System.out.println(json.toString(4)); // Print it with specified indentation

The order of fields in JSON is random per definition. A specific order is subject to parser implementation.

Warning :-Presenting view controllers on detached view controllers is discouraged

In my case, I've a sampleViewController's view added as a subview, then tries to present a popover from the view of sampleViewController (here self instead a UIViewController instance):

[self.view addSubview:sampleViewController.view];

The right way should be below:

// make sure the vc has been added as a child view controller as well
[self addChildViewController:sampleViewController];
[self.view addSubview:sampleViewController.view];
[sampleViewController didMoveToParentViewController:self];

B.t.w., this also works for the case that present a popover form a tableview cell, you just need to make sure the tableview controller has been added as child view controller as well.

C convert floating point to int

my_var = (int)my_var;

As simple as that. Basically you don't need it if the variable is int.

What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?

I have tried to make note about these and have collected and written examples from a java perspective.

HTTP for Java Developers

Reverse Ajax - Old style

Async Handling on server side

Reverse Ajax - New style

Server Sent Events

Putting it here for any java developer who is looking into the same subject.

How to set env variable in Jupyter notebook

A related (short-term) solution is to store your environment variables in a single file, with a predictable format, that can be sourced when starting a terminal and/or read into the notebook. For example, I have a file, .env, that has my environment variable definitions in the format VARIABLE_NAME=VARIABLE_VALUE (no blank lines or extra spaces). You can source this file in the .bashrc or .bash_profile files when beginning a new terminal session and you can read this into a notebook with something like,

import os
env_vars = !cat ../script/.env
for var in env_vars:
    key, value = var.split('=')
    os.environ[key] = value

I used a relative path to show that this .env file can live anywhere and be referenced relative to the directory containing the notebook file. This also has the advantage of not displaying the variable values within your code anywhere.

Get top first record from duplicate records having no unique identity

Using DISTINCT should do it:

SELECT DISTINCT id, uname, tel
FROM YourTable

Though you could really do with having a primary key on that table, a way to uniquely identify each record. I'd be considering sticking an IDENTITY column on the table

How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?

You can do this easily with ReSharper 8 or later. The ctorf, ctorp, and ctorfp snippets generate constructors that populate all the fields, properties, or fields and properties of a class.

How can I clone an SQL Server database on the same server in SQL Server 2008 Express?

Script based on Joe answer (detach, copy files, attach both).

  1. Run Managment Studio as Administrator account.

It's not necessary, but maybe access denied error on executing.

  1. Configure sql server for execute xp_cmdshel
EXEC sp_configure 'show advanced options', 1
GO
RECONFIGURE
GO
EXEC sp_configure 'xp_cmdshell', 1
GO
RECONFIGURE
GO
  1. Run script, but type your db names in @dbName and @copyDBName variables before.
USE master;
GO 

DECLARE @dbName NVARCHAR(255) = 'Products'
DECLARE @copyDBName NVARCHAR(255) = 'Products_branch'

-- get DB files
CREATE TABLE ##DBFileNames([FileName] NVARCHAR(255))
EXEC('
    INSERT INTO ##DBFileNames([FileName])
    SELECT [filename] FROM ' + @dbName + '.sys.sysfiles')

-- drop connections
EXEC('ALTER DATABASE ' + @dbName + ' SET OFFLINE WITH ROLLBACK IMMEDIATE')

EXEC('ALTER DATABASE ' + @dbName + ' SET SINGLE_USER')

-- detach
EXEC('EXEC sp_detach_db @dbname = ''' + @dbName + '''')

-- copy files
DECLARE @filename NVARCHAR(255), @path NVARCHAR(255), @ext NVARCHAR(255), @copyFileName NVARCHAR(255), @command NVARCHAR(MAX) = ''
DECLARE 
    @oldAttachCommand NVARCHAR(MAX) = 
        'CREATE DATABASE ' + @dbName + ' ON ', 
    @newAttachCommand NVARCHAR(MAX) = 
        'CREATE DATABASE ' + @copyDBName + ' ON '

DECLARE curs CURSOR FOR 
SELECT [filename] FROM ##DBFileNames
OPEN curs  
FETCH NEXT FROM curs INTO @filename
WHILE @@FETCH_STATUS = 0  
BEGIN
    SET @path = REVERSE(RIGHT(REVERSE(@filename),(LEN(@filename)-CHARINDEX('\', REVERSE(@filename),1))+1))
    SET @ext = RIGHT(@filename,4)
    SET @copyFileName = @path + @copyDBName + @ext

    SET @command = 'EXEC master..xp_cmdshell ''COPY "' + @filename + '" "' + @copyFileName + '"'''
    PRINT @command
    EXEC(@command);

    SET @oldAttachCommand = @oldAttachCommand + '(FILENAME = "' + @filename + '"),'
    SET @newAttachCommand = @newAttachCommand + '(FILENAME = "' + @copyFileName + '"),'

    FETCH NEXT FROM curs INTO @filename
END
CLOSE curs 
DEALLOCATE curs

-- attach
SET @oldAttachCommand = LEFT(@oldAttachCommand, LEN(@oldAttachCommand) - 1) + ' FOR ATTACH'
SET @newAttachCommand = LEFT(@newAttachCommand, LEN(@newAttachCommand) - 1) + ' FOR ATTACH'

-- attach old db
PRINT @oldAttachCommand
EXEC(@oldAttachCommand)

-- attach copy db
PRINT @newAttachCommand
EXEC(@newAttachCommand)

DROP TABLE ##DBFileNames

Pandas: Appending a row to a dataframe and specify its index label

The name of the Series becomes the index of the row in the DataFrame:

In [99]: df = pd.DataFrame(np.random.randn(8, 4), columns=['A','B','C','D'])

In [100]: s = df.xs(3)

In [101]: s.name = 10

In [102]: df.append(s)
Out[102]: 
           A         B         C         D
0  -2.083321 -0.153749  0.174436  1.081056
1  -1.026692  1.495850 -0.025245 -0.171046
2   0.072272  1.218376  1.433281  0.747815
3  -0.940552  0.853073 -0.134842 -0.277135
4   0.478302 -0.599752 -0.080577  0.468618
5   2.609004 -1.679299 -1.593016  1.172298
6  -0.201605  0.406925  1.983177  0.012030
7   1.158530 -2.240124  0.851323 -0.240378
10 -0.940552  0.853073 -0.134842 -0.277135

mysql stored-procedure: out parameter

SET out_number=SQRT(input_number); 

Instead of this write:

select SQRT(input_number); 

Please don't write SET out_number and your input parameter should be:

PROCEDURE `test`.`my_sqrt`(IN input_number INT, OUT out_number FLOAT) 

How to get HTTP Response Code using Selenium WebDriver

It is possible to get the response code of a http request using Selenium and Chrome or Firefox. All you have to do is start either Chrome or Firefox in logging mode. I will show you some examples below.

java + Selenium + Chrome Here is an example of java + Selenium + Chrome, but I guess that it can be done in any language (python, c#, ...).

All you need to do is tell chromedriver to do "Network.enable". This can be done by enabling Performance logging.

LoggingPreferences logPrefs = new LoggingPreferences();
logPrefs.enable(LogType.PERFORMANCE, Level.ALL);
cap.setCapability(CapabilityType.LOGGING_PREFS, logPrefs);

After the request is done, all you have to do is get and iterate the Perfomance logs and find "Network.responseReceived" for the requested url:

LogEntries logs = driver.manage().logs().get("performance");

Here is the code:

import java.util.Iterator;
import java.util.logging.Level;

import org.json.JSONException;
import org.json.JSONObject;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.chrome.ChromeOptions;
import org.openqa.selenium.logging.LogEntries;
import org.openqa.selenium.logging.LogEntry;
import org.openqa.selenium.logging.LogType;
import org.openqa.selenium.logging.LoggingPreferences;
import org.openqa.selenium.remote.CapabilityType;
import org.openqa.selenium.remote.DesiredCapabilities;

public class TestResponseCode
{
    public static void main(String[] args)
    {
        // simple page (without many resources so that the output is
        // easy to understand
        String url = "http://www.york.ac.uk/teaching/cws/wws/webpage1.html";

        DownloadPage(url);
    }

    private static void DownloadPage(String url)
    {
        ChromeDriver driver = null;

        try
        {
            ChromeOptions options = new ChromeOptions();
            // add whatever extensions you need
            // for example I needed one of adding proxy, and one for blocking
            // images
            // options.addExtensions(new File(file, "proxy.zip"));
            // options.addExtensions(new File("extensions",
            // "Block-image_v1.1.crx"));

            DesiredCapabilities cap = DesiredCapabilities.chrome();
            cap.setCapability(ChromeOptions.CAPABILITY, options);

            // set performance logger
            // this sends Network.enable to chromedriver
            LoggingPreferences logPrefs = new LoggingPreferences();
            logPrefs.enable(LogType.PERFORMANCE, Level.ALL);
            cap.setCapability(CapabilityType.LOGGING_PREFS, logPrefs);

            driver = new ChromeDriver(cap);

            // navigate to the page
            System.out.println("Navigate to " + url);
            driver.navigate().to(url);

            // and capture the last recorded url (it may be a redirect, or the
            // original url)
            String currentURL = driver.getCurrentUrl();

            // then ask for all the performance logs from this request
            // one of them will contain the Network.responseReceived method
            // and we shall find the "last recorded url" response
            LogEntries logs = driver.manage().logs().get("performance");

            int status = -1;

            System.out.println("\nList of log entries:\n");

            for (Iterator<LogEntry> it = logs.iterator(); it.hasNext();)
            {
                LogEntry entry = it.next();

                try
                {
                    JSONObject json = new JSONObject(entry.getMessage());

                    System.out.println(json.toString());

                    JSONObject message = json.getJSONObject("message");
                    String method = message.getString("method");

                    if (method != null
                            && "Network.responseReceived".equals(method))
                    {
                        JSONObject params = message.getJSONObject("params");

                        JSONObject response = params.getJSONObject("response");
                        String messageUrl = response.getString("url");

                        if (currentURL.equals(messageUrl))
                        {
                            status = response.getInt("status");

                            System.out.println(
                                    "---------- bingo !!!!!!!!!!!!!! returned response for "
                                            + messageUrl + ": " + status);

                            System.out.println(
                                    "---------- bingo !!!!!!!!!!!!!! headers: "
                                            + response.get("headers"));
                        }
                    }
                } catch (JSONException e)
                {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }

            System.out.println("\nstatus code: " + status);
        } finally
        {
            if (driver != null)
            {
                driver.quit();
            }
        }
    }
}

The output looks like this:

    Navigate to http://www.york.ac.uk/teaching/cws/wws/webpage1.html

    List of log entries:

    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameAttached","params":{"parentFrameId":"172.1","frameId":"172.2"}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameStartedLoading","params":{"frameId":"172.2"}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameNavigated","params":{"frame":{"securityOrigin":"://","loaderId":"172.1","name":"chromedriver dummy frame","id":"172.2","mimeType":"text/html","parentId":"172.1","url":"about:blank"}}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameStoppedLoading","params":{"frameId":"172.2"}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameStartedLoading","params":{"frameId":"3928.1"}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.requestWillBeSent","params":{"request":{"headers":{"Upgrade-Insecure-Requests":"1","User-Agent":"Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36"},"initialPriority":"VeryHigh","method":"GET","mixedContentType":"none","url":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html"},"frameId":"3928.1","requestId":"3928.1","documentURL":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html","initiator":{"type":"other"},"loaderId":"3928.1","wallTime":1.47619492749007E9,"type":"Document","timestamp":20226.652971}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.responseReceived","params":{"frameId":"3928.1","requestId":"3928.1","response":{"headers":{"Accept-Ranges":"bytes","Keep-Alive":"timeout=4, max=100","Cache-Control":"max-age=300","Server":"Apache/2.2.22 (Ubuntu)","Connection":"Keep-Alive","Content-Encoding":"gzip","Vary":"Accept-Encoding","Expires":"Tue, 11 Oct 2016 14:13:47 GMT","Content-Length":"1957","Date":"Tue, 11 Oct 2016 14:08:47 GMT","Content-Type":"text/html"},"connectionReused":false,"timing":{"pushEnd":0,"workerStart":-1,"proxyEnd":-1,"workerReady":-1,"sslEnd":-1,"pushStart":0,"requestTime":20226.65335,"sslStart":-1,"dnsStart":0,"sendEnd":31.6569999995409,"connectEnd":31.4990000006219,"connectStart":0,"sendStart":31.5860000009707,"dnsEnd":0,"receiveHeadersEnd":115.645999998378,"proxyStart":-1},"encodedDataLength":-1,"remotePort":80,"mimeType":"text/html","headersText":"HTTP/1.1 200 OK\r\nDate: Tue, 11 Oct 2016 14:08:47 GMT\r\nServer: Apache/2.2.22 (Ubuntu)\r\nAccept-Ranges: bytes\r\nCache-Control: max-age=300\r\nExpires: Tue, 11 Oct 2016 14:13:47 GMT\r\nVary: Accept-Encoding\r\nContent-Encoding: gzip\r\nContent-Length: 1957\r\nKeep-Alive: timeout=4, max=100\r\nConnection: Keep-Alive\r\nContent-Type: text/html\r\n\r\n","securityState":"neutral","requestHeadersText":"GET /teaching/cws/wws/webpage1.html HTTP/1.1\r\nHost: www.york.ac.uk\r\nConnection: keep-alive\r\nUpgrade-Insecure-Requests: 1\r\nUser-Agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36\r\nAccept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8\r\nAccept-Encoding: gzip, deflate, sdch\r\nAccept-Language: en-GB,en-US;q=0.8,en;q=0.6\r\n\r\n","url":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html","protocol":"http/1.1","fromDiskCache":false,"fromServiceWorker":false,"requestHeaders":{"Accept":"text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8","Upgrade-Insecure-Requests":"1","Connection":"keep-alive","User-Agent":"Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36","Host":"www.york.ac.uk","Accept-Encoding":"gzip, deflate, sdch","Accept-Language":"en-GB,en-US;q=0.8,en;q=0.6"},"remoteIPAddress":"144.32.128.84","statusText":"OK","connectionId":11,"status":200},"loaderId":"3928.1","type":"Document","timestamp":20226.770012}}}
    ---------- bingo !!!!!!!!!!!!!! returned response for http://www.york.ac.uk/teaching/cws/wws/webpage1.html: 200
    ---------- bingo !!!!!!!!!!!!!! headers: {"Accept-Ranges":"bytes","Keep-Alive":"timeout=4, max=100","Cache-Control":"max-age=300","Server":"Apache/2.2.22 (Ubuntu)","Connection":"Keep-Alive","Content-Encoding":"gzip","Vary":"Accept-Encoding","Expires":"Tue, 11 Oct 2016 14:13:47 GMT","Content-Length":"1957","Date":"Tue, 11 Oct 2016 14:08:47 GMT","Content-Type":"text/html"}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.dataReceived","params":{"dataLength":2111,"requestId":"3928.1","encodedDataLength":1460,"timestamp":20226.770425}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameNavigated","params":{"frame":{"securityOrigin":"http://www.york.ac.uk","loaderId":"3928.1","id":"3928.1","mimeType":"text/html","url":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html"}}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.dataReceived","params":{"dataLength":1943,"requestId":"3928.1","encodedDataLength":825,"timestamp":20226.782673}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.loadingFinished","params":{"requestId":"3928.1","encodedDataLength":2285,"timestamp":20226.770199}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.loadEventFired","params":{"timestamp":20226.799391}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.frameStoppedLoading","params":{"frameId":"3928.1"}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Page.domContentEventFired","params":{"timestamp":20226.845769}}}
    {"webview":"3b8eaedb-bd0f-4baa-938d-4aee4039abfe","message":{"method":"Network.requestWillBeSent","params":{"request":{"headers":{"Referer":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html","User-Agent":"Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36"},"initialPriority":"High","method":"GET","mixedContentType":"none","url":"http://www.york.ac.uk/favicon.ico"},"frameId":"3928.1","requestId":"3928.2","documentURL":"http://www.york.ac.uk/teaching/cws/wws/webpage1.html","initiator":{"type":"other"},"loaderId":"3928.1","wallTime":1.47619492768527E9,"type":"Other","timestamp":20226.848174}}}

    status code: 200

java + Selenium + Firefox I have finally found the trick for Firefox too. You need to start firefox using MOZ_LOG and MOZ_LOG_FILE environment variables, and log http requests at debug level (4 = PR_LOG_DEBUG) - map.put("MOZ_LOG", "timestamp,sync,nsHttp:4"). Save the log in a temporary file. After that, get the content of the saved log file and parse it for the response code (using some simple regular expressions). First detect the start of the request, identifying its id (nsHttpChannel::BeginConnect [this=000000CED8094000]), then at the second step, find the response code for that request id (nsHttpChannel::ProcessResponse [this=000000CED8094000 httpStatus=200]).

import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.io.FileUtils;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.firefox.GeckoDriverService;

public class TestFirefoxResponse
{
  public static void main(String[] args)
      throws InterruptedException, IOException
  {
    GeckoDriverService service = null;

    // tell firefox to log http requests
    // at level 4 = PR_LOG_DEBUG: debug messages, notices
    // you could log everything at level 5, but the log file will 
    // be larger. 
    // create a temporary log file that will be parsed for
    // response code
    Map<String, String> map = new HashMap<String, String>();
    map.put("MOZ_LOG", "timestamp,sync,nsHttp:4");
    File tempFile = File.createTempFile("mozLog", ".txt");    
    map.put("MOZ_LOG_FILE", tempFile.getAbsolutePath());      

    GeckoDriverService.Builder builder = new GeckoDriverService.Builder();
    service = builder.usingAnyFreePort()
      .withEnvironment(map)
      .build();

    service.start();      

    WebDriver driver = new FirefoxDriver(service);

    // test 200
     String url = "https://api.ipify.org/?format=text";
    // test 404
    // String url = "https://www.advancedwebranking.com/lsdkjflksdjfldksfj";
    driver.get(url);

    driver.quit();

    String logContent = FileUtils.readFileToString(tempFile);

    ParseLog(logContent, url);
  }

  private static void ParseLog(String logContent, String url) throws MalformedURLException
  {
    // this is how the log looks like when the request starts
    // I have to get the id of the request using a regular expression
    // and use that id later to get the response
    //
    //    2017-11-02 14:14:01.170000 UTC - [Main Thread]: D/nsHttp nsHttpChannel::BeginConnect [this=000000BFF27A5000]
    //    2017-11-02 14:14:01.170000 UTC - [Main Thread]: D/nsHttp host=api.ipify.org port=-1
    //    2017-11-02 14:14:01.170000 UTC - [Main Thread]: D/nsHttp uri=https://api.ipify.org/?format=text
    String pattern = "BeginConnect \\[this=(.*?)\\](?:.*?)uri=(.*?)\\s";

    Pattern p = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
    Matcher m = p.matcher(logContent);

    String urlID = null;
    while (m.find())
    {
      String id = m.group(1);
      String uri = m.group(2);

      if (uri.equals(url))
      {
        urlID = id;
        break;
      }      
    }

    System.out.println("request id = " + urlID);

    // this is how the response looks like in the log file
    // ProcessResponse [this=000000CED8094000 httpStatus=200]
    // I will use another regular espression to get the httpStatus
    //
    //    2017-11-02 14:45:39.296000 UTC - [Main Thread]: D/nsHttp nsHttpChannel::OnStartRequest [this=000000CED8094000 request=000000CED8014BB0 status=0]
    //    2017-11-02 14:45:39.296000 UTC - [Main Thread]: D/nsHttp nsHttpChannel::ProcessResponse [this=000000CED8094000 httpStatus=200]    

    pattern = "ProcessResponse \\[this=" + urlID + " httpStatus=(.*?)\\]";

    p = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
    m = p.matcher(logContent);

    if (m.find())
    {
      String responseCode = m.group(1);
      System.out.println("response code found " + responseCode);
    }
    else
    {
      System.out.println("response code not found");
    }
  }
}

The output for this will be

request id = 0000007653D67000 response code found 200

The response headers can also be found in the log file. You can get them if you want.

    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp http response [
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   HTTP/1.1 404 Not Found
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Accept-Ranges: bytes
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Cache-control: no-cache="set-cookie"
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Content-Type: text/html; charset=utf-8
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Date: Thu, 02 Nov 2017 14:54:36 GMT
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   ETag: "7969-55bc076a61e80"
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Last-Modified: Tue, 17 Oct 2017 16:17:46 GMT
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Server: Apache/2.4.23 (Amazon) PHP/5.6.24
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Set-Cookie: AWSELB=5F256FFA816C8E72E13AE0B12A17A3D540582F804C87C5FEE323AF3C9B638FD6260FF473FF64E44926DD26221AAD2E9727FD739483E7E4C31784C7A495796B416146EE83;PATH=/
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Content-Length: 31081
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Connection: keep-alive
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp     OriginalHeaders
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Accept-Ranges: bytes
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Cache-control: no-cache="set-cookie"
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Content-Type: text/html; charset=utf-8
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Date: Thu, 02 Nov 2017 14:54:36 GMT
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   ETag: "7969-55bc076a61e80"
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Last-Modified: Tue, 17 Oct 2017 16:17:46 GMT
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Server: Apache/2.4.23 (Amazon) PHP/5.6.24
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Set-Cookie: AWSELB=5F256FFA816C8E72E13AE0B12A17A3D540582F804C87C5FEE323AF3C9B638FD6260FF473FF64E44926DD26221AAD2E9727FD739483E7E4C31784C7A495796B416146EE83;PATH=/
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Content-Length: 31081
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp   Connection: keep-alive
    2017-11-02 14:54:36.775000 UTC - [Socket Thread]: I/nsHttp ]
    2017-11-02 14:54:36.775000 UTC - [Main Thread]: D/nsHttp nsHttpChannel::OnStartRequest [this=0000008A65D85000 request=0000008A65D1F900 status=0]
    2017-11-02 14:54:36.775000 UTC - [Main Thread]: D/nsHttp nsHttpChannel::ProcessResponse [this=0000008A65D85000 httpStatus=404]

How do I change an HTML selected option using JavaScript?

You could also change select.options.selectedIndex DOM attribute like this:

_x000D_
_x000D_
function selectOption(index){ _x000D_
  document.getElementById("select_id").options.selectedIndex = index;_x000D_
}
_x000D_
<p>_x000D_
<select id="select_id">_x000D_
  <option selected>first option</option>_x000D_
  <option>second option</option>_x000D_
  <option>third option</option>_x000D_
</select>_x000D_
</p>_x000D_
<p>_x000D_
  <button onclick="selectOption(0);">Select first option</button>_x000D_
  <button onclick="selectOption(1);">Select second option</button>_x000D_
  <button onclick="selectOption(2);">Select third option</button>_x000D_
</p>
_x000D_
_x000D_
_x000D_

Conda environments not showing up in Jupyter Notebook

I encountered this problem when using vscode server. In the conda environment named "base", I installed the 1.2.0 version of opennmt-py, but I want to run jupyter notebook in the conda environment "opennmt2", which contains code using opennmt-py 2.0. I solved the problem by reinstalling jupyter in conda(opennmt2).

conda install jupyter

After reinstalling, executing jupyter notebook in the opennmt2 environment will execute the newly installed jupyter

where jupyter 
/root/miniconda3/envs/opennmt2/bin/jupyter
/root/miniconda3/bin/jupyter

How to search a string in a single column (A) in excel using VBA

Below are two methods that are superior to looping. Both handle a "no-find" case.

  1. The VBA equivalent of a normal function VLOOKUP with error-handling if the variable doesn't exist (INDEX/MATCH may be a better route than VLOOKUP, ie if your two columns A and B were in reverse order, or were far apart)
  2. VBAs FIND method (matching a whole string in column A given I use the xlWhole argument)

    Sub Method1()
    Dim strSearch As String
    Dim strOut As String
    Dim bFailed As Boolean
    
    strSearch = "trees"
    
    On Error Resume Next
    strOut = Application.WorksheetFunction.VLookup(strSearch, Range("A:B"), 2, False)
    If Err.Number <> 0 Then bFailed = True
    On Error GoTo 0
    
    If Not bFailed Then
    MsgBox "corresponding value is " & vbNewLine & strOut
    Else
    MsgBox strSearch & " not found"
    End If
    End Sub
    
    Sub Method2()
        Dim rng1 As Range
        Dim strSearch As String
        strSearch = "trees"
        Set rng1 = Range("A:A").Find(strSearch, , xlValues, xlWhole)
        If Not rng1 Is Nothing Then
            MsgBox "Find has matched " & strSearch & vbNewLine & "corresponding cell is " & rng1.Offset(0, 1)
        Else
            MsgBox strSearch & " not found"
        End If
    End Sub
    

How to get multiple selected values of select box in php?

foreach ($_POST["select2"] as $selectedOption)
{    
    echo $selectedOption."\n";  
}

Disable HTTP OPTIONS, TRACE, HEAD, COPY and UNLOCK methods in IIS

For anyone looking for a UI option using IIS Manager.

  1. Open the Website in IIS Manager
  2. Go To Request Filtering and open the Request Filtering Window.
  3. Go to Verbs Tab and Add HTTP Verbs to "Allow Verb..." or "Deny Verb...". This allow to add the HTTP Verbs in the "Deny Verb.." Collection.

Request Filtering Window in IIS Manager Request Filtering Window in IIS Manager

Add Verb... or Deny Verb... enter image description here

IFrame: This content cannot be displayed in a frame

The X-Frame-Options is defined in the Http Header and not in the <head> section of the page you want to use in the iframe.

Accepted values are: DENY, SAMEORIGIN and ALLOW-FROM "url"

How to pass a JSON array as a parameter in URL

I know this could be a later post, but, for new visitors I will share my solution, as the OP was asking for a way to pass a JSON object via GET (not POST as suggested in other answers).

  1. Take the JSON object and convert it to string (JSON.stringify)
  2. Take the string and encode it in Base64 (you can find some useful info on this here
  3. Append it to the URL and make the GET call
  4. Reverse the process. decode and parse it into an object

I have used this in some cases where I only can do GET calls and it works. Also, this solution is practically cross language.

PHP ini file_get_contents external url

The setting you are looking for is allow_url_fopen.

You have two ways of getting around it without changing php.ini, one of them is to use fsockopen(), and the other is to use cURL.

I recommend using cURL over file_get_contents() anyways, since it was built for this.

What is the best way to conditionally apply a class?

Here is another option that works well when ng-class can't be used (for example when styling SVG):

ng-attr-class="{{someBoolean && 'class-when-true' || 'class-when-false' }}"

(I think you need to be on latest unstable Angular to use ng-attr-, I'm currently on 1.1.4)

Join vs. sub-query

MSDN Documentation for SQL Server says

Many Transact-SQL statements that include subqueries can be alternatively formulated as joins. Other questions can be posed only with subqueries. In Transact-SQL, there is usually no performance difference between a statement that includes a subquery and a semantically equivalent version that does not. However, in some cases where existence must be checked, a join yields better performance. Otherwise, the nested query must be processed for each result of the outer query to ensure elimination of duplicates. In such cases, a join approach would yield better results.

so if you need something like

select * from t1 where exists select * from t2 where t2.parent=t1.id

try to use join instead. In other cases, it makes no difference.

I say: Creating functions for subqueries eliminate the problem of cluttter and allows you to implement additional logic to subqueries. So I recommend creating functions for subqueries whenever possible.

Clutter in code is a big problem and the industry has been working on avoiding it for decades.

PHP Get Site URL Protocol - http vs https

Because testing port number is not a good practice according to me, my solution is:

define('HTTPS', isset($_SERVER['HTTPS']) && filter_var($_SERVER['HTTPS'], FILTER_VALIDATE_BOOLEAN));

The HTTPSconstant returns TRUE if $_SERVER['HTTPS'] is set and equals to "1", "true", "on" or "yes". Returns FALSE otherwise.

Wpf DataGrid Add new row

Just simply use this Style of DataGridRow:

<DataGrid.RowStyle>
        <Style TargetType="DataGridRow">
            <Setter Property="IsEnabled" Value="{Binding RelativeSource={RelativeSource Self},Path=IsNewItem,Mode=OneWay}" />
        </Style>
</DataGrid.RowStyle>

Is there are way to make a child DIV's width wider than the parent DIV using CSS?

I used this:

HTML

<div class="container">
 <div class="parent">
  <div class="child">
   <div class="inner-container"></div>
  </div>
 </div>
</div>

CSS

.container {
  overflow-x: hidden;
}

.child {
  position: relative;
  width: 200%;
  left: -50%;
}

.inner-container{
  max-width: 1179px;
  margin:0 auto;
}

Android Studio and android.support.v4.app.Fragment: cannot resolve symbol

I'm running the most current version of AndroidStudio to date (11/10/2015) -- v1.4 (build AI-141.2288178, built on September 28, 2015) and I built my project and everything worked fine. Then after a few hours of my computer being inactive I came back, edited some code that had nothing to do with the support libraries and started seeing :

cannot resolve symbol 'fragmentactivity' and I was seeing red highlighted items related to fragmentactivity in the AndroidStudio editor.

The solution was to simply do a

Build...Rebuild Project...

I only mention this so others might see it and know it is happening out there.

Compile error: "g++: error trying to exec 'cc1plus': execvp: No such file or directory"

I had the same issue with gcc "gnat1" and it was due to the path being wrong. Gnat1 was on version 4.6 but I was executing version 4.8.1, which I had installed. As a temporary solution, I copied gnat1 from 4.6 and pasted under the 4.8.1 folder.

The path to gcc on my computer is /usr/lib/gcc/i686-linux-gnu/

You can find the path by using the find command:

find /usr -name "gnat1"

In your case you would look for cc1plus:

find /usr -name "cc1plus"

Of course, this is a quick solution and a more solid answer would be fixing the broken path.

How do I return an int from EditText? (Android)

First of all get a string from an EDITTEXT and then convert this string into integer like

      String no=myTxt.getText().toString();       //this will get a string                               
      int no2=Integer.parseInt(no);              //this will get a no from the string

Redirect to external URL with return in laravel

For Laravel 8 you can also use

Route::redirect('/here', '/there');
//or
Route::permanentRedirect('/here', '/there');

This also works with external URLs

See: https://austencam.com/posts/setting-up-an-m1-mac-for-laravel-development-with-homebrew-php-mysql-valet-and-redis

Getting "Lock wait timeout exceeded; try restarting transaction" even though I'm not using a transaction

mysql> set innodb_lock_wait_timeout=100

Query OK, 0 rows affected (0.02 sec)

mysql> show variables like 'innodb_lock_wait_timeout';
+--------------------------+-------+
| Variable_name            | Value |
+--------------------------+-------+
| innodb_lock_wait_timeout | 100   |
+--------------------------+-------+

Now trigger the lock again. You have 100 seconds time to issue a SHOW ENGINE INNODB STATUS\G to the database and see which other transaction is locking yours.

Can Flask have optional URL parameters?

@app.route('/', defaults={'path': ''})
@app.route('/< path:path >')
def catch_all(path):
    return 'You want path: %s' % path

http://flask.pocoo.org/snippets/57/

How to not wrap contents of a div?

Forcing the buttons stay in the same line will make them go beyond the fixed width of the div they are in. If you are okay with that then you can make another div inside the div you already have. The new div in turn will hold the buttons and have the fixed width of however much space the two buttons need to stay in one line.

Here is an example:

<div id="parentDiv" style="width: [less-than-what-buttons-need]px;">
    <div id="holdsButtons" style="width: [>=-than-buttons-need]px;">
       <button id="button1">1</button>
       <button id="button2">2</button>
    </div>
</div>

You may want to consider overflow property for the chunk of the content outside of the parentDiv border.

Good luck!

Clearing state es6 React

Problem

The accepted answer:

const initialState = {
    /* etc */
};

class MyComponent extends Component {
    constructor(props) {
        super(props)
        this.state = initialState;
    }
    reset() {
        this.setState(initialState);
    }
    /* etc */
}

unfortunately is not correct.

initialState is passed as a reference to this.state, so whenever you change state you also change initialState (const doesn't really matter here). The result is that you can never go back to initialState.

Solution

You have to deep copy initialState to state, then it will work. Either write a deep copy function yourself or use some existing module like this.

How to Allow Remote Access to PostgreSQL database

In order to remotely access a PostgreSQL database, you must set the two main PostgreSQL configuration files:

postgresql.conf
pg_hba.conf

Here is a brief description about how you can set them (note that the following description is purely indicative: To configure a machine safely, you must be familiar with all the parameters and their meanings)

First of all configure PostgreSQL service to listen on port 5432 on all network interfaces in Windows 7 machine:
open the file postgresql.conf (usually located in C:\Program Files\PostgreSQL\9.2\data) and sets the parameter

listen_addresses = '*'

Check the network address of WindowsXP virtual machine, and sets parameters in pg_hba.conf file (located in the same directory of postgresql.conf) so that postgresql can accept connections from virtual machine hosts.
For example, if the machine with Windows XP have 192.168.56.2 IP address, add in the pg_hba.conf file:

host all all 192.168.56.1/24 md5

this way, PostgreSQL will accept connections from all hosts on the network 192.168.1.XXX.

Restart the PostgreSQL service in Windows 7 (Services-> PosgreSQL 9.2: right click and restart sevice). Install pgAdmin on windows XP machine and try to connect to PostgreSQL.

HttpWebRequest-The remote server returned an error: (400) Bad Request

400 Bad request Error will be thrown due to incorrect authentication entries.

  1. Check if your API URL is correct or wrong. Don't append or prepend spaces.
  2. Verify that your username and password are valid. Please check any spelling mistake(s) while entering.

Note: Mostly due to Incorrect authentication entries due to spell changes will occur 400 Bad request.

Get Current date in epoch from Unix shell script

The Unix Date command will display in epoch time

the command is

date +"%s"

https://linux.die.net/man/1/date

Edit: Some people have observed you asked for days, so it's the result of that command divided by 86,400

How to save a plot into a PDF file without a large margin around

What do you mean by "the proper size"? MATLAB figures are like vector graphics, so you can basically choose the size you want on your plot.

You can set the size of the paper and the position of the figure with the function set.

Example:

plot(epx(1:5));
set(gcf, 'PaperPosition', [0 0 5 5]); %Position plot at left hand corner with width 5 and height 5.
set(gcf, 'PaperSize', [5 5]); %Set the paper to have width 5 and height 5.
saveas(gcf, 'test', 'pdf') %Save figure

Enter image description here

The above code will remove most of the borders, but not all. This is because the left-hand corner ([0 0] in the position vector) is not the "true" left-hand corner. To remove more of the borders, you can adjust the PaperPosition and PaperSize vectors.

Example:

plot(exp(1:5))
set(gcf, 'PaperPosition', [-0.5 -0.25 6 5.5]); %Position the plot further to the left and down. Extend the plot to fill entire paper.
set(gcf, 'PaperSize', [5 5]); %Keep the same paper size
saveas(gcf, 'test', 'pdf')

Enter image description here

Add two textbox values and display the sum in a third textbox automatically

Well, base on your code, you would put onkeyup=sum() in each text box txt1 and txt2

Counting unique / distinct values by group in a data frame

You can just use the built-in R functions tapply with length

tapply(myvec$order_no, myvec$name, FUN = function(x) length(unique(x)))

Child inside parent with min-height: 100% not inheriting height

This is what works for me with percentage-based height and parent still growing according to children height. Works fine in Firefox, Chrome and Safari.

_x000D_
_x000D_
.parent {_x000D_
  position: relative;_x000D_
  min-height: 100%;_x000D_
}_x000D_
_x000D_
.child {_x000D_
  min-height: 100vh;_x000D_
}
_x000D_
<div class="parent">_x000D_
    <div class="child"></div>_x000D_
  </div>
_x000D_
_x000D_
_x000D_

How to execute Python code from within Visual Studio Code

So there are four ways to run Python in Visual Studio Code so far:

  1. Via an integrated terminal (come on, it's integrated! So technically you run it from within Visual Studio Code ;)
  • No need to install any extension.
  • No need to create and configure anything (assuming that you already have python in your $PATH).
  • ^Space (open terminal) and python my_file.py (run file).
  1. Via custom Task (accepted Fenton's answer):
  • No need to install any extension.
  • Default Visual Studio Code's way of doing things.
  • Beware not to copy-paste the answer because its problemMatcher.pattern.regexp is broken and it hangs the editor. It's better to either delete problemMatcher or change the regexp to at least ^\\s+(.*)$.
  1. Via Code Runner extension (@JanHan's answer):
  • Need to configure code-runner.executorMap in User Settings (add path to your python).
  • Very helpful extension especially if you run not only Python in Visual Studio Code.
  1. Via Microsoft's official Python extension (vlad2135's answer):
  • Need to create launch.js (a couple of clicks in Visual Studio Code's Debug tab).
  • The extension is a must-have for those who wants to use Visual Studio Code as a primary IDE for Python.

Why em instead of px?

You probably want to use em for font sizes until IE6 is gone (from your site). Px will be alright when page zooming (as opposed to text zooming) becomes the standard behaviour.

Traingamer already provided the neccessary links.

How to push object into an array using AngularJS

You should try this way. It will definitely work.

(function() {

var app = angular.module('myApp', []);

 app.controller('myController', ['$scope', function($scope) {

    $scope.myText = "Object Push inside ";

    $scope.arrayText = [

        ];

    $scope.addText = function() {
        $scope.arrayText.push(this.myText);
    }

 }]);

})();

In your case $scope.arrayText is an object. You should initialize as a array.

Converting map to struct

I adapt dave's answer, and add a recursive feature. I'm still working on a more user friendly version. For example, a number string in the map should be able to be converted to int in the struct.

package main

import (
    "fmt"
    "reflect"
)

func SetField(obj interface{}, name string, value interface{}) error {

    structValue := reflect.ValueOf(obj).Elem()
    fieldVal := structValue.FieldByName(name)

    if !fieldVal.IsValid() {
        return fmt.Errorf("No such field: %s in obj", name)
    }

    if !fieldVal.CanSet() {
        return fmt.Errorf("Cannot set %s field value", name)
    }

    val := reflect.ValueOf(value)

    if fieldVal.Type() != val.Type() {

        if m,ok := value.(map[string]interface{}); ok {

            // if field value is struct
            if fieldVal.Kind() == reflect.Struct {
                return FillStruct(m, fieldVal.Addr().Interface())
            }

            // if field value is a pointer to struct
            if fieldVal.Kind()==reflect.Ptr && fieldVal.Type().Elem().Kind() == reflect.Struct {
                if fieldVal.IsNil() {
                    fieldVal.Set(reflect.New(fieldVal.Type().Elem()))
                }
                // fmt.Printf("recursive: %v %v\n", m,fieldVal.Interface())
                return FillStruct(m, fieldVal.Interface())
            }

        }

        return fmt.Errorf("Provided value type didn't match obj field type")
    }

    fieldVal.Set(val)
    return nil

}

func FillStruct(m map[string]interface{}, s interface{}) error {
    for k, v := range m {
        err := SetField(s, k, v)
        if err != nil {
            return err
        }
    }
    return nil
}

type OtherStruct struct {
    Name string
    Age  int64
}


type MyStruct struct {
    Name string
    Age  int64
    OtherStruct *OtherStruct
}



func main() {
    myData := make(map[string]interface{})
    myData["Name"]        = "Tony"
    myData["Age"]         = int64(23)
    OtherStruct := make(map[string]interface{})
    myData["OtherStruct"] = OtherStruct
    OtherStruct["Name"]   = "roxma"
    OtherStruct["Age"]    = int64(23)

    result := &MyStruct{}
    err := FillStruct(myData,result)
    fmt.Println(err)
    fmt.Printf("%v %v\n",result,result.OtherStruct)
}

There is an error in XML document (1, 41)

In my case I had a float value expected where xml had a null value so be sure to search for float and int data type in your xsd map

How to use Javascript to read local text file and read line by line?

Without jQuery:

document.getElementById('file').onchange = function(){

  var file = this.files[0];

  var reader = new FileReader();
  reader.onload = function(progressEvent){
    // Entire file
    console.log(this.result);

    // By lines
    var lines = this.result.split('\n');
    for(var line = 0; line < lines.length; line++){
      console.log(lines[line]);
    }
  };
  reader.readAsText(file);
};

HTML:

<input type="file" name="file" id="file">

Remember to put your javascript code after the file field is rendered.

Is there a link to the "latest" jQuery library on Google APIs?

You can use the latest version of the jQuery library by any of the following.

  • Google Ajax API CDN (also supports SSL via HTTPS)

    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2"></script>
    

    /jquery.min.js

  • Microsoft CDN (also aupports SSL via HTTPS)

    <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.7.2.min.js"></script>
    

    Ajax CDN Announcement, Microsoft Ajax CDN Documentation

  • jQuery CDN (via Media Temple)

     <script type="text/javascript" src=" http://code.jquery.com/jquery-1.7.2.min.js"></script>
    

    ** Minified version

     <script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.js"></script>
    

    ** Development (Full) version

How to open, read, and write from serial port in C?

For demo code that conforms to POSIX standard as described in Setting Terminal Modes Properly and Serial Programming Guide for POSIX Operating Systems, the following is offered.
This code should execute correctly using Linux on x86 as well as ARM (or even CRIS) processors.
It's essentially derived from the other answer, but inaccurate and misleading comments have been corrected.

This demo program opens and initializes a serial terminal at 115200 baud for non-canonical mode that is as portable as possible.
The program transmits a hardcoded text string to the other terminal, and delays while the output is performed.
The program then enters an infinite loop to receive and display data from the serial terminal.
By default the received data is displayed as hexadecimal byte values.

To make the program treat the received data as ASCII codes, compile the program with the symbol DISPLAY_STRING, e.g.

 cc -DDISPLAY_STRING demo.c

If the received data is ASCII text (rather than binary data) and you want to read it as lines terminated by the newline character, then see this answer for a sample program.


#define TERMINAL    "/dev/ttyUSB0"

#include <errno.h>
#include <fcntl.h> 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>

int set_interface_attribs(int fd, int speed)
{
    struct termios tty;

    if (tcgetattr(fd, &tty) < 0) {
        printf("Error from tcgetattr: %s\n", strerror(errno));
        return -1;
    }

    cfsetospeed(&tty, (speed_t)speed);
    cfsetispeed(&tty, (speed_t)speed);

    tty.c_cflag |= (CLOCAL | CREAD);    /* ignore modem controls */
    tty.c_cflag &= ~CSIZE;
    tty.c_cflag |= CS8;         /* 8-bit characters */
    tty.c_cflag &= ~PARENB;     /* no parity bit */
    tty.c_cflag &= ~CSTOPB;     /* only need 1 stop bit */
    tty.c_cflag &= ~CRTSCTS;    /* no hardware flowcontrol */

    /* setup for non-canonical mode */
    tty.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
    tty.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
    tty.c_oflag &= ~OPOST;

    /* fetch bytes as they become available */
    tty.c_cc[VMIN] = 1;
    tty.c_cc[VTIME] = 1;

    if (tcsetattr(fd, TCSANOW, &tty) != 0) {
        printf("Error from tcsetattr: %s\n", strerror(errno));
        return -1;
    }
    return 0;
}

void set_mincount(int fd, int mcount)
{
    struct termios tty;

    if (tcgetattr(fd, &tty) < 0) {
        printf("Error tcgetattr: %s\n", strerror(errno));
        return;
    }

    tty.c_cc[VMIN] = mcount ? 1 : 0;
    tty.c_cc[VTIME] = 5;        /* half second timer */

    if (tcsetattr(fd, TCSANOW, &tty) < 0)
        printf("Error tcsetattr: %s\n", strerror(errno));
}


int main()
{
    char *portname = TERMINAL;
    int fd;
    int wlen;
    char *xstr = "Hello!\n";
    int xlen = strlen(xstr);

    fd = open(portname, O_RDWR | O_NOCTTY | O_SYNC);
    if (fd < 0) {
        printf("Error opening %s: %s\n", portname, strerror(errno));
        return -1;
    }
    /*baudrate 115200, 8 bits, no parity, 1 stop bit */
    set_interface_attribs(fd, B115200);
    //set_mincount(fd, 0);                /* set to pure timed read */

    /* simple output */
    wlen = write(fd, xstr, xlen);
    if (wlen != xlen) {
        printf("Error from write: %d, %d\n", wlen, errno);
    }
    tcdrain(fd);    /* delay for output */


    /* simple noncanonical input */
    do {
        unsigned char buf[80];
        int rdlen;

        rdlen = read(fd, buf, sizeof(buf) - 1);
        if (rdlen > 0) {
#ifdef DISPLAY_STRING
            buf[rdlen] = 0;
            printf("Read %d: \"%s\"\n", rdlen, buf);
#else /* display hex */
            unsigned char   *p;
            printf("Read %d:", rdlen);
            for (p = buf; rdlen-- > 0; p++)
                printf(" 0x%x", *p);
            printf("\n");
#endif
        } else if (rdlen < 0) {
            printf("Error from read: %d: %s\n", rdlen, strerror(errno));
        } else {  /* rdlen == 0 */
            printf("Timeout from read\n");
        }               
        /* repeat read to get full message */
    } while (1);
}

For an example of an efficient program that provides buffering of received data yet allows byte-by-byte handing of the input, then see this answer.


MySQL error: key specification without a key length

DROP that table and again run Spring Project. That might help. Sometime you are overriding foreignKey.

How to compare two JSON objects with the same elements in a different order equal?

Decode them and compare them as mgilson comment.

Order does not matter for dictionary as long as the keys, and values matches. (Dictionary has no order in Python)

>>> {'a': 1, 'b': 2} == {'b': 2, 'a': 1}
True

But order is important in list; sorting will solve the problem for the lists.

>>> [1, 2] == [2, 1]
False
>>> [1, 2] == sorted([2, 1])
True

>>> a = '{"errors": [{"error": "invalid", "field": "email"}, {"error": "required", "field": "name"}], "success": false}'
>>> b = '{"errors": [{"error": "required", "field": "name"}, {"error": "invalid", "field": "email"}], "success": false}'
>>> a, b = json.loads(a), json.loads(b)
>>> a['errors'].sort()
>>> b['errors'].sort()
>>> a == b
True

Above example will work for the JSON in the question. For general solution, see Zero Piraeus's answer.

Heroku + node.js error (Web process failed to bind to $PORT within 60 seconds of launch)

In my case, neither the port nor the host was the problem. The index.js was divided into 2 files. server.js:

//server.js
const express = require('express')
const path = require('path')

const app = express()

app.use(express.static(path.resolve(__dirname, 'public')));
// and all the other stuff
module.exports = app

//app.js
const app = require('./server');
const port = process.env.PORT || 3000;
app.listen(port, '0.0.0.0', () => {
    console.log('Server is running s on port: ' + port)
});

from package.json we ran node app.js.

Apparently that was the problem. Once I combined the two into one file, the Heroku app deployed as expected.

How to find out if a Python object is a string?

For a nice duck-typing approach for string-likes that has the bonus of working with both Python 2.x and 3.x:

def is_string(obj):
    try:
        obj + ''
        return True
    except TypeError:
        return False

wisefish was close with the duck-typing before he switched to the isinstance approach, except that += has a different meaning for lists than + does.

Pyspark: Exception: Java gateway process exited before sending the driver its port number

I have the same error in running pyspark in pycharm. I solved the problem by adding JAVA_HOME in pycharm's environment variables.

jQuery get textarea text

Methinks the word "console" is causing the confusion.

If you want to emulate an old-style full/half duplex console, you'd use something like this:

$('console').keyup(function(event){
    $.get("url", { keyCode: event.which }, ... );
    return true;
});

event.which has the key that was pressed. For backspace handling, event.which === 8.

How can I solve the error LNK2019: unresolved external symbol - function?

Since I want my project to compile to a stand-alone EXE file, I linked the UnitTest project to the function.obj file generated from function.cpp and it works.

Right click on the 'UnitTest1' project ? Configuration Properties ? Linker ? Input ? Additional Dependencies ? add "..\MyProjectTest\Debug\function.obj".

Failed to resolve version for org.apache.maven.archetypes

The problem may also come from that you haven't set MAVEN_HOME environment variable. So the Maven embedded in Eclipse can't do its job to download the archetype.Check if that variable is set upfront.

Beautiful way to remove GET-variables with PHP?

You can use the server variables for this, for example $_SERVER['REQUEST_URI'], or even better: $_SERVER['PHP_SELF'].

Preferred Java way to ping an HTTP URL for availability

Consider using the Restlet framework, which has great semantics for this sort of thing. It's powerful and flexible.

The code could be as simple as:

Client client = new Client(Protocol.HTTP);
Response response = client.get(url);
if (response.getStatus().isError()) {
    // uh oh!
}

How to compute the similarity between two text documents?

If you are more interested in measuring semantic similarity of two pieces of text, I suggest take a look at this gitlab project. You can run it as a server, there is also a pre-built model which you can use easily to measure the similarity of two pieces of text; even though it is mostly trained for measuring the similarity of two sentences, you can still use it in your case.It is written in java but you can run it as a RESTful service.

Another option also is DKPro Similarity which is a library with various algorithm to measure the similarity of texts. However, it is also written in java.

code example:

// this similarity measure is defined in the dkpro.similarity.algorithms.lexical-asl package
// you need to add that to your .pom to make that example work
// there are some examples that should work out of the box in dkpro.similarity.example-gpl 
TextSimilarityMeasure measure = new WordNGramJaccardMeasure(3);    // Use word trigrams

String[] tokens1 = "This is a short example text .".split(" ");   
String[] tokens2 = "A short example text could look like that .".split(" ");

double score = measure.getSimilarity(tokens1, tokens2);

System.out.println("Similarity: " + score);

Difference between EXISTS and IN in SQL?

If you are using the IN operator, the SQL engine will scan all records fetched from the inner query. On the other hand if we are using EXISTS, the SQL engine will stop the scanning process as soon as it found a match.

How to use linux command line ftp with a @ sign in my username?

I simply type ftp hostdomain.com and the very next prompt asked me to enter a name, if it wasn't the same as my current user.

I guess it depends on how your FTP is configured. That is, whether it assumes the same username (if not provided) or asks. the good news is that even without a solution, next time you face this it might Just Work™ for you :D

Could not find module "@angular-devkit/build-angular"

In my case, the issue is, because of missing dependencies. The dependencies are missing, because I've forgotten to call:

npm install

After calling the above command, all required dependencies are loaded in node_modules, and that is no more issue

How can I encode a string to Base64 in Swift?

Swift 4.2

"abcd1234".data(using: .utf8)?.base64EncodedString()

Is there a way to use shell_exec without waiting for the command to complete?

On Windows 2003, to call another script without waiting, I used this:

$commandString = "start /b c:\\php\\php.EXE C:\\Inetpub\\wwwroot\\mysite.com\\phpforktest.php --passmsg=$testmsg"; 
pclose(popen($commandString, 'r'));

This only works AFTER giving changing permissions on cmd.exe - add Read and Execute for IUSR_YOURMACHINE (I also set write to Deny).

Reading content from URL with Node.js

try using the on error event of the client to find the issue.

var http = require('http');

var options = {
    host: 'google.com',
    path: '/'
}
var request = http.request(options, function (res) {
    var data = '';
    res.on('data', function (chunk) {
        data += chunk;
    });
    res.on('end', function () {
        console.log(data);

    });
});
request.on('error', function (e) {
    console.log(e.message);
});
request.end();

How to declare a type as nullable in TypeScript?

Union type is in my mind best option in this case:

interface Employee{
   id: number;
   name: string;
   salary: number | null;
}

// Both cases are valid
let employe1: Employee = { id: 1, name: 'John', salary: 100 };
let employe2: Employee = { id: 1, name: 'John', salary: null };

EDIT : For this to work as expected, you should enable the strictNullChecks in tsconfig.

What is the difference between HTTP_HOST and SERVER_NAME in PHP?

$_SERVER['SERVER_NAME'] is based on your web servers configuration. $_SERVER['HTTP_HOST'] is based on the request from the client.

Jackson how to transform JsonNode to ArrayNode without casting?

Yes, the Jackson manual parser design is quite different from other libraries. In particular, you will notice that JsonNode has most of the functions that you would typically associate with array nodes from other API's. As such, you do not need to cast to an ArrayNode to use. Here's an example:

JSON:

{
    "objects" : ["One", "Two", "Three"]
}

Code:

final String json = "{\"objects\" : [\"One\", \"Two\", \"Three\"]}";

final JsonNode arrNode = new ObjectMapper().readTree(json).get("objects");
if (arrNode.isArray()) {
    for (final JsonNode objNode : arrNode) {
        System.out.println(objNode);
    }
}

Output:

"One"
"Two"
"Three"

Note the use of isArray to verify that the node is actually an array before iterating. The check is not necessary if you are absolutely confident in your datas structure, but its available should you need it (and this is no different from most other JSON libraries).

Update row with data from another row in the same table

Update MyTable
Set Value = (
                Select Min( T2.Value )
                From MyTable As T2
                Where T2.Id <> MyTable.Id
                    And T2.Name = MyTable.Name
                )
Where ( Value Is Null Or Value = '' )
    And Exists  (
                Select 1
                From MyTable As T3
                Where T3.Id <> MyTable.Id
                    And T3.Name = MyTable.Name
                )

react-native :app:installDebug FAILED

In my case, I manually delete the app-debug.apk file and run it again.

Firing events on CSS class changes in jQuery

Just a proof of concept:

Look at the gist to see some annotations and stay up-to-date:

https://gist.github.com/yckart/c893d7db0f49b1ea4dfb

(function ($) {
  var methods = ['addClass', 'toggleClass', 'removeClass'];

  $.each(methods, function (index, method) {
    var originalMethod = $.fn[method];

    $.fn[method] = function () {
      var oldClass = this[0].className;
      var result = originalMethod.apply(this, arguments);
      var newClass = this[0].className;

      this.trigger(method, [oldClass, newClass]);

      return result;
    };
  });
}(window.jQuery || window.Zepto));

The usage is quite simple, just add a new listender on the node you want to observe and manipulate the classes as usually:

var $node = $('div')

// listen to class-manipulation
.on('addClass toggleClass removeClass', function (e, oldClass, newClass) {
  console.log('Changed from %s to %s due %s', oldClass, newClass, e.type);
})

// make some changes
.addClass('foo')
.removeClass('foo')
.toggleClass('foo');

Debugging "Element is not clickable at point" error

I had the same issue, tried all offered solutions but they did not work for me. eventually I used this:

JavascriptExecutor js = (JavascriptExecutor) driver;
js.executeScript("var evt = document.createEvent('MouseEvents');" + "evt.initMouseEvent('click',true, true, window, 0, 0, 0, 0, 0, false, false, false, false, 0,null);" + "arguments[0].dispatchEvent(evt);", findElement(element));

Hope this helps

ImproperlyConfigured: You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings

Django needs your application-specific settings. Since it is already inside your manage.py, just use that. The faster, but perhaps temporary, solution is:

python manage.py shell

React Native: Getting the position of an element

I needed to find the position of an element inside a ListView and used this snippet that works kind of like .offset:

const UIManager = require('NativeModules').UIManager;
const handle = React.findNodeHandle(this.refs.myElement);
UIManager.measureLayoutRelativeToParent(
  handle, 
  (e) => {console.error(e)}, 
  (x, y, w, h) => {
    console.log('offset', x, y, w, h);
  });

This assumes I had a ref='myElement' on my component.

Google Maps API v3 adding an InfoWindow to each marker

for Earth plugin APIs, create the balloon outside your loop and pass your counter to the function to get unique contents for each placemark!

function createBalloon(placemark, i, event) {
            var p = placemark;
            var j = i;
            google.earth.addEventListener(p, 'click', function (event) {
                    // prevent the default balloon from popping up
                    event.preventDefault();
                    var balloon = ge.createHtmlStringBalloon('');
                    balloon.setFeature(event.getTarget());

                    balloon.setContentString('iframePath#' + j);

                    ge.setBalloon(balloon);
            });
        }

Can I loop through a table variable in T-SQL?

Here is my version of the same solution...

    declare @id int

        SELECT @id = min(fPat.PatientID)
        FROM tbPatients fPat
        WHERE (fPat.InsNotes is not null AND DataLength(fPat.InsNotes)>0)

while @id is not null
begin
    SELECT fPat.PatientID, fPat.InsNotes
    FROM tbPatients fPat
    WHERE (fPat.InsNotes is not null AND DataLength(fPat.InsNotes)>0) AND fPat.PatientID=@id

    SELECT @id = min(fPat.PatientID)
    FROM tbPatients fPat
    WHERE (fPat.InsNotes is not null AND DataLength(fPat.InsNotes)>0)AND fPat.PatientID>@id

end

open program minimized via command prompt

Try:

start  "" "C:\Program Files (x86)\Microsoft Office\Office12\WINWORD.EXE" --new-window/min

I had the same problem, but I was trying to open chrome.exe maximized. If I put the /min anywhere else in the command line, like before or after the empty title, it was ignored.

How to set .net Framework 4.5 version in IIS 7 application pool

Go to "Run" and execute this:

%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -ir

NOTE: run as administrator.

Array[n] vs Array[10] - Initializing array with variable vs real number

In C++, variable length arrays are not legal. G++ allows this as an "extension" (because C allows it), so in G++ (without being -pedantic about following the C++ standard), you can do:

int n = 10;
double a[n]; // Legal in g++ (with extensions), illegal in proper C++

If you want a "variable length array" (better called a "dynamically sized array" in C++, since proper variable length arrays aren't allowed), you either have to dynamically allocate memory yourself:

int n = 10;
double* a = new double[n]; // Don't forget to delete [] a; when you're done!

Or, better yet, use a standard container:

int n = 10;
std::vector<double> a(n); // Don't forget to #include <vector>

If you still want a proper array, you can use a constant, not a variable, when creating it:

const int n = 10;
double a[n]; // now valid, since n isn't a variable (it's a compile time constant)

Similarly, if you want to get the size from a function in C++11, you can use a constexpr:

constexpr int n()
{
    return 10;
}

double a[n()]; // n() is a compile time constant expression

Remote branch is not showing up in "git branch -r"

I had the same issue. It seems the easiest solution is to just remove the remote, readd it, and fetch.

What would be the best method to code heading/title for <ul> or <ol>, Like we have <caption> in <table>?

how about making the heading a list-element with different styles like so

<ul>
 <li class="heading">heading</li>
 <li>list item</li>
 <li>list item</li>
 <li>list item</li>
 <li>list item</li>
</ul>

and the CSS

ul .heading {font-weight: normal; list-style: none;}

additionally, use a reset CSS to set margins and paddings right on the ul and li. here's a good reset CSS. once you've reset the margins and paddings, you can apply some margin on the list-elements other than the one's with the heading class, to indent them.

Why use prefixes on member variables in C++ classes

The main reason for a member prefix is to distinguish between a member function local and a member variable with the same name. This is useful if you use getters with the name of the thing.

Consider:

class person
{
public:
    person(const std::string& full_name)
        : full_name_(full_name)
    {}

    const std::string& full_name() const { return full_name_; }
private:
    std::string full_name_;
};

The member variable could not be called full_name in this case. You need to rename the member function to get_full_name() or decorate the member variable somehow.

JPA - Persisting a One to Many relationship

One way to do that is to set the cascade option on you "One" side of relationship:

class Employee {
   // 

   @OneToMany(cascade = {CascadeType.PERSIST})
   private Set<Vehicles> vehicles = new HashSet<Vehicles>();

   //
}

by this, when you call

Employee savedEmployee = employeeDao.persistOrMerge(newEmployee);

it will save the vehicles too.

OnClick vs OnClientClick for an asp:CheckBox?

For those of you who got here looking for the server-side OnClick handler it is OnCheckedChanged

PHP Warning Permission denied (13) on session_start()

It seems that you don't have WRITE permission on /tmp.

Edit the configuration variable session.save_path with the function session_save_path() to 1 directory above public_html (so external users wouldn't access the info).

Fastest way to download a GitHub project

When you are on a project page, you can press the 'Download ZIP' button which is located under the "Clone or Download" drop down:

enter image description here

This allows you to download the most recent version of the code as a zip archive.

If you aren't seeing that button, it is likely because you aren't on the main project page. To get there, click on the left-most tab labeled "<> Code".

How to use npm with node.exe?

Search all .npmrc file in your system.

Please verify that the path you have given is correct. If not please remove the incorrect path.

Print <div id="printarea"></div> only?

Best css to fit space empty height:

@media print {
  body * {
    visibility: hidden;
    height:0;
  }
  #section-to-print, #section-to-print * {
    visibility: visible;
    height:auto;
  }
  #section-to-print {
    position: absolute;
    left: 0;
    top: 0;
  }
}

Get current language in CultureInfo

I tried {CultureInfo currentCulture = Thread.CurrentThread.CurrentCulture;} but it didn`t work for me, since my UI culture was different from my number/currency culture. So I suggest you to use:

CultureInfo currentCulture = Thread.CurrentThread.CurrentUICulture;

This will give you the culture your UI is (texts on windows, message boxes, etc).

Foreach in a Foreach in MVC View

Assuming your controller's action method is something like this:

public ActionResult AllCategories(int id = 0)
{
    return View(db.Categories.Include(p => p.Products).ToList());
}

Modify your models to be something like this:

public class Product
{
    [Key]
    public int ID { get; set; }
    public int CategoryID { get; set; }
    //new code
    public virtual Category Category { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
    public string Path { get; set; }

    //remove code below
    //public virtual ICollection<Category> Categories { get; set; }
}

public class Category
{
    [Key]
    public int CategoryID { get; set; }
    public string Name { get; set; }
    //new code
    public virtual ICollection<Product> Products{ get; set; }
}

Then your since now the controller takes in a Category as Model (instead of a Product):

foreach (var category in Model)
{
    <h3><u>@category.Name</u></h3>
    <div>
        <ul>    
            @foreach (var product in Model.Products)
            {
                // cut for brevity, need to add back more code from original
                <li>@product.Title</li>
            }
        </ul>
    </div>
}

UPDATED: Add ToList() to the controller return statement.

Reverse order of foreach list items

array_reverse() does not alter the source array, but returns a new array. (See array_reverse().) So you either need to store the new array first or just use function within the declaration of your for loop.

<?php 
    $input = array('a', 'b', 'c');
    foreach (array_reverse($input) as $value) {
        echo $value."\n";
    }
?>

The output will be:

c
b
a

So, to address to OP, the code becomes:

<?php
    $j=1;     
    foreach ( array_reverse($skills_nav) as $skill ) {
        $a = '<li><a href="#" data-filter=".'.$skill->slug.'">';
        $a .= $skill->name;                 
        $a .= '</a></li>';
        echo $a;
        echo "\n";
        $j++;
}

Lastly, I'm going to guess that the $j was either a counter used in an initial attempt to get a reverse walk of $skills_nav, or a way to count the $skills_nav array. If the former, it should be removed now that you have the correct solution. If the latter, it can be replaced, outside of the loop, with a $j = count($skills_nav).

Powershell: convert string to number

Simply casting the string as an int won't work reliably. You need to convert it to an int32. For this you can use the .NET convert class and its ToInt32 method. The method requires a string ($strNum) as the main input, and the base number (10) for the number system to convert to. This is because you can not only convert to the decimal system (the 10 base number), but also to, for example, the binary system (base 2).

Give this method a try:

[string]$strNum = "1.500"
[int]$intNum = [convert]::ToInt32($strNum, 10)

$intNum

How to terminate a process in vbscript

The Win32_Process class provides access to both 32-bit and 64-bit processes when the script is run from a 64-bit command shell.

If this is not an option for you, you can try using the taskkill command:

Dim oShell : Set oShell = CreateObject("WScript.Shell")

' Launch notepad '
oShell.Run "notepad"
WScript.Sleep 3000

' Kill notepad '
oShell.Run "taskkill /im notepad.exe", , True

How to add new line into txt file

var Line = textBox1.Text + "," + textBox2.Text;

File.AppendAllText(@"C:\Documents\m2.txt", Line + Environment.NewLine);

What is the difference between URL parameters and query strings?

Parameters are key-value pairs that can appear inside URL path, and start with a semicolon character (;).

Query string appears after the path (if any) and starts with a question mark character (?).

Both parameters and query string contain key-value pairs.

In a GET request, parameters appear in the URL itself:

<scheme>://<username>:<password>@<host>:<port>/<path>;<parameters>?<query>#<fragment>

In a POST request, parameters can appear in the URL itself, but also in the datastream (as known as content).

Query string is always a part of the URL.

Parameters can be buried in form-data datastream when using POST method so they may not appear in the URL. Yes a POST request can define parameters as form data and in the URL, and this is not inconsistent because parameters can have several values.

I've found no explaination for this behavior so far. I guess it might be useful sometimes to "unhide" parameters from a POST request, or even let the code handling a GET request share some parts with the code handling a POST. Of course this can work only with server code supporting parameters in a URL.

Until you get better insights, I suggest you to use parameters only in form-data datastream of POST requests.

Sources:

What Every Developer Should Know About URLs

RFC 3986

Java constant examples (Create a java file having only constants)

This question is old. But I would like to mention an other approach. Using Enums for declaring constant values. Based on the answer of Nandkumar Tekale, the Enum can be used as below:

Enum:

public enum Planck {
    REDUCED();
    public static final double PLANCK_CONSTANT = 6.62606896e-34;
    public static final double PI = 3.14159;
    public final double REDUCED_PLANCK_CONSTANT;

    Planck() {
        this.REDUCED_PLANCK_CONSTANT = PLANCK_CONSTANT / (2 * PI);
    }

    public double getValue() {
        return REDUCED_PLANCK_CONSTANT;
    }
}

Client class:

public class PlanckClient {

    public static void main(String[] args) {
        System.out.println(getReducedPlanckConstant());
        // or using Enum itself as below:
        System.out.println(Planck.REDUCED.getValue());
    }

    public static double getReducedPlanckConstant() {
        return Planck.PLANCK_CONSTANT / (2 * Planck.PI);
    }

}

Reference : The usage of Enums for declaring constant fields is suggested by Joshua Bloch in his Effective Java book.

The I/O operation has been aborted because of either a thread exit or an application request

What I do when it happens is Disable the COM port into the Device Manager and Enable it again.

It stop the communications with another program or thread and become free for you.

I hope this works for you. Regards.

JavaScript: Alert.Show(message) From ASP.NET Code-behind

Your code does not compile. The string you have terminates unexpectedly;

string script = "<script type=";

That's effectively what you've written. You need to escape your double quotes:

string script = "<script type=\"text/javascript\">alert('" + cleanMessage + "');</script>";

This kind of thing should be painfully obvious since your source code coloring should be completely jacked.

How do I generate a random int number?

For strong random seed I always use CryptoRNG and not Time.

using System;
using System.Security.Cryptography;

public class Program
{
    public static void Main()
    {
        var random = new Random(GetSeed());
        Console.WriteLine(random.Next());
    }

    public static int GetSeed() 
    {
        using (var rng = new RNGCryptoServiceProvider())
        {
            var intBytes = new byte[4];
            rng.GetBytes(intBytes);
            return BitConverter.ToInt32(intBytes, 0);
        }
    }
}

How to understand nil vs. empty vs. blank in Ruby

Don't forget any? which is generally !empty?. In Rails I typically check for the presence of something at the end of a statement with if something or unless something then use blank? where needed since it seems to work everywhere.

SQL: sum 3 columns when one column has a null value?

looks like you want to SUM all the columns (I'm not sure where "sum 3 columns" comes from), not just TotalHoursM, so try this:

SELECT 
    SUM(    ISNULL(TotalHoursM  ,0)
          + ISNULL(TotalHoursT  ,0)
          + ISNULL(TotalHoursW  ,0)
          + ISNULL(TotalHoursTH ,0)
          + ISNULL(TotalHoursF  ,0) 
       ) AS TOTAL
    FROM LeaveRequest

Good examples using java.util.logging

There are many examples and also of different types for logging. Take a look at the java.util.logging package.

Example code:

import java.util.logging.Logger;

public class Main {

  private static Logger LOGGER = Logger.getLogger("InfoLogging");

  public static void main(String[] args) {
    LOGGER.info("Logging an INFO-level message");
  }
}

Without hard-coding the class name:

import java.util.logging.Logger;

public class Main {
  private static final Logger LOGGER = Logger.getLogger(
    Thread.currentThread().getStackTrace()[0].getClassName() );

  public static void main(String[] args) {
    LOGGER.info("Logging an INFO-level message");
  }
}

Inline elements shifting when made bold on hover

I use text-shadow solution as some others mentioned here:

text-shadow: 0 0 0.01px;

the difference is that I do not specify shadow color, so this solution is universal for all font colors.

How can I compare two time strings in the format HH:MM:SS?

I think you can put it like this.

_x000D_
_x000D_
var a = "10:20:45";_x000D_
var b = "5:10:10";_x000D_
_x000D_
var timeA = new Date();_x000D_
timeA.setHours(a.split(":")[0],a.split(":")[1],a.split(":")[2]);_x000D_
timeB = new Date();_x000D_
timeB.setHours(b.split(":")[0],b.split(":")[1],b.split(":")[2]);_x000D_
_x000D_
var x= "B is later than A";_x000D_
if(timeA>timeB) x = "A is later than B";_x000D_
document.getElementById("demo").innerHTML = x;
_x000D_
<p id="demo"></p>
_x000D_
_x000D_
_x000D_

Put text at bottom of div

I think that's better to use flex boxes (compatibility) than the absolute position. Here's example from me in pure css.

_x000D_
_x000D_
.container{_x000D_
  background-color:green;_x000D_
  height:500px;_x000D_
  _x000D_
  /*FLEX BOX */_x000D_
  display: -ms-flexbox;_x000D_
    display: -webkit-flex;_x000D_
    display: flex;_x000D_
    -webkit-flex-direction: column;_x000D_
    -ms-flex-direction: column;_x000D_
    flex-direction: column;_x000D_
    -webkit-flex-wrap: nowrap;_x000D_
    -ms-flex-wrap: nowrap;_x000D_
    flex-wrap: nowrap;_x000D_
    -webkit-justify-content: flex-start;_x000D_
    -ms-flex-pack: start;_x000D_
    justify-content: flex-start;_x000D_
    -webkit-align-content: stretch;_x000D_
    -ms-flex-line-pack: stretch;_x000D_
    align-content: stretch;_x000D_
    -webkit-align-items: flex-start;_x000D_
    -ms-flex-align: start;_x000D_
    align-items: flex-start;_x000D_
}_x000D_
_x000D_
.elem1{_x000D_
  background-color:red;_x000D_
  padding:20px;_x000D_
  _x000D_
   /*FLEX BOX CHILD */_x000D_
 -webkit-order: 0;_x000D_
    -ms-flex-order: 0;_x000D_
    order: 0;_x000D_
    -webkit-flex: 0 1 auto;_x000D_
    -ms-flex: 0 1 auto;_x000D_
    flex: 0 1 auto;_x000D_
    -webkit-align-self: flex-end;_x000D_
    -ms-flex-item-align: end;_x000D_
    align-self: flex-end;_x000D_
 _x000D_
}
_x000D_
<div class="container">_x000D_
 TOP OF CONTAINER _x000D_
<div class="elem1">_x000D_
  Nam pretium turpis et arcu. Sed a libero. Sed mollis, eros et ultrices tempus, mauris ipsum aliquam libero, non adipiscing dolor urna a orci._x000D_
_x000D_
Mauris sollicitudin fermentum libero. Pellentesque libero tortor, tincidunt et, tincidunt eget, semper nec, quam. Quisque id mi._x000D_
_x000D_
Donec venenatis vulputate lorem. Maecenas ullamcorper, dui et placerat feugiat, eros pede varius nisi, condimentum viverra felis nunc et lorem. Curabitur vestibulum aliquam leo._x000D_
</div>_x000D_
_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to sleep for five seconds in a batch file/cmd

Can't we do waitfor /T 180?

waitfor /T 180 pause will result in "ERROR: Timed out waiting for 'pause'."

waitfor /T 180 pause >nul will sweep that "error" under the rug

The waitfor command should be there in Windows OS after Win95

In the past I've downloaded a executable named sleep that will work on the command line after you put it in your path.

For example: sleep shutdown -r -f /m \\yourmachine although shutdown now has -t option built in

Validate select box

Just add a class of required to the select

<select id="select" class="required">

Speech input for visually impaired users without the need to tap the screen

The only way to get the iOS dictation is to sign up yourself through Nuance: http://dragonmobile.nuancemobiledeveloper.com/ - it's expensive, because it's the best. Presumably, Apple's contract prevents them from exposing an API.

The built in iOS accessibility features allow immobilized users to access dictation (and other keyboard buttons) through tools like VoiceOver and Assistive Touch. It may not be worth reinventing this if your users might be familiar with these tools.

How do you clear a stringstream variable?

This should be the most reliable way regardless of the compiler:

m=std::stringstream();

I can't find my git.exe file in my Github folder

The last update for "windows git" did move the git.exe file from the /bin folder to the /cmd folder. So, to use git with IDEs such as webStorm or Android Studio you can use the path :

C:\Users\<user>\AppData\Local\GitHub\PortableGit_<..numbers..>\cmd\git.exe

But if you want to have linux-like commands such as git, ssh, ls, cp under windows powerShell or cmd add to your windows PATH variables :

C:\Users\<user>\AppData\Local\GitHub\PortableGit_<...numbers...>\usr\bin

change <user> and <...numbers...> to your values and reboot!

Also, you will have to update this everytime git updates since it might change the portable folder name. If folder structure changes I will update this post.

Thx @dennisschagt for the comment above! ;)

Python: find position of element in array

As Aaron states, you can use .index(value), but because that will throw an exception if value is not present, you should handle that case, even if you're sure it will never happen. A couple options are by checking its presence first, such as:

if value in my_list:
    value_index = my_list.index(value)

or by catching the exception as in:

try:
    value_index = my_list.index(value)
except:
    value_index = -1

You can never go wrong with proper error handling.

How to manually send HTTP POST requests from Firefox or Chrome browser?

You can post requests directly from the browser with ReqBin. No plugin or desktop app is required.

https://reqbin.com

Change the class from factor to numeric of many columns in a data frame

Based on @SDahm's answer, this was an "optimal" solution for my tibble:

data %<>% lapply(type.convert) %>% as.data.table()

This requires dplyr and magrittr.

How to add "on delete cascade" constraints?

Usage:

select replace_foreign_key('user_rates_posts', 'post_id', 'ON DELETE CASCADE');

Function:

CREATE OR REPLACE FUNCTION 
    replace_foreign_key(f_table VARCHAR, f_column VARCHAR, new_options VARCHAR) 
RETURNS VARCHAR
AS $$
DECLARE constraint_name varchar;
DECLARE reftable varchar;
DECLARE refcolumn varchar;
BEGIN

SELECT tc.constraint_name, ccu.table_name AS foreign_table_name, ccu.column_name AS foreign_column_name 
FROM 
    information_schema.table_constraints AS tc 
    JOIN information_schema.key_column_usage AS kcu
      ON tc.constraint_name = kcu.constraint_name
    JOIN information_schema.constraint_column_usage AS ccu
      ON ccu.constraint_name = tc.constraint_name
WHERE constraint_type = 'FOREIGN KEY' 
   AND tc.table_name= f_table AND kcu.column_name= f_column
INTO constraint_name, reftable, refcolumn;

EXECUTE 'alter table ' || f_table || ' drop constraint ' || constraint_name || 
', ADD CONSTRAINT ' || constraint_name || ' FOREIGN KEY (' || f_column || ') ' ||
' REFERENCES ' || reftable || '(' || refcolumn || ') ' || new_options || ';';

RETURN 'Constraint replaced: ' || constraint_name || ' (' || f_table || '.' || f_column ||
 ' -> ' || reftable || '.' || refcolumn || '); New options: ' || new_options;

END;
$$ LANGUAGE plpgsql;

Be aware: this function won't copy attributes of initial foreign key. It only takes foreign table name / column name, drops current key and replaces with new one.

Parsing a comma-delimited std::string

Simple Copy/Paste function, based on the boost tokenizer.

void strToIntArray(std::string string, int* array, int array_len) {
  boost::tokenizer<> tok(string);
  int i = 0;
  for(boost::tokenizer<>::iterator beg=tok.begin(); beg!=tok.end();++beg){
    if(i < array_len)
      array[i] = atoi(beg->c_str());
    i++;
}