[javascript] Download and open PDF file using Ajax

I have an action class that generates a PDF. The contentType is set appropriately.

public class MyAction extends ActionSupport 
{
   public String execute() {
    ...
    ...
    File report = signedPdfExporter.generateReport(xyzData, props);

    inputStream = new FileInputStream(report);
    contentDisposition = "attachment=\"" + report.getName() + "\"";
    contentType = "application/pdf";
    return SUCCESS;
   }
}

I call this action through an Ajax call. I don't know the way to deliver this stream to browser. I tried a few things but nothing worked.

$.ajax({
    type: "POST",
    url: url,
    data: wireIdList,
    cache: false,
    success: function(response)
    {
        alert('got response');
        window.open(response);
    },
    error: function (XMLHttpRequest, textStatus, errorThrown) 
    {
        alert('Error occurred while opening fax template' 
              + getAjaxErrorString(textStatus, errorThrown));
    }
});

The above gives the error:

Your browser sent a request that this server could not understand.

Do you have to do it with Ajax? Coouldn't it be a possibility to load it in an iframe?

You could use this plugin which creates a form, and submits it, then removes it from the page.

jQuery.download = function(url, data, method) {
    //url and data options required
    if (url && data) {
        //data can be string of parameters or array/object
        data = typeof data == 'string' ? data : jQuery.param(data);
        //split params into form inputs
        var inputs = '';
        jQuery.each(data.split('&'), function() {
            var pair = this.split('=');
            inputs += '<input type="hidden" name="' + pair[0] +
                '" value="' + pair[1] + '" />';
        });
        //send request
        jQuery('<form action="' + url +
                '" method="' + (method || 'post') + '">' + inputs + '</form>')
            .appendTo('body').submit().remove();
    };
};


$.download(
    '/export.php',
    'filename=mySpreadsheet&format=xls&content=' + spreadsheetData
);

This worked for me. Found this plugin here

What worked for me is the following code, as the server function is retrieving File(memoryStream.GetBuffer(), "application/pdf", "fileName.pdf");:

$http.get( fullUrl, { responseType: 'arraybuffer' })
            .success(function (response) {
                var blob = new Blob([response], { type: 'application/pdf' });

                if (window.navigator && window.navigator.msSaveOrOpenBlob) {
                    window.navigator.msSaveOrOpenBlob(blob); // for IE
                }
                else {
                    var fileURL = URL.createObjectURL(blob);
                    var newWin = window.open(fileURL);
                    newWin.focus();
                    newWin.reload();
                }
});

This snippet is for angular js users which will face the same problem, Note that the response file is downloaded using a programmed click event. In this case , the headers were sent by server containing filename and content/type.

$http({
    method: 'POST', 
    url: 'DownloadAttachment_URL',
    data: { 'fileRef': 'filename.pdf' }, //I'm sending filename as a param
    headers: { 'Authorization': $localStorage.jwt === undefined ? jwt : $localStorage.jwt },
    responseType: 'arraybuffer',
}).success(function (data, status, headers, config) {
    headers = headers();
    var filename = headers['x-filename'];
    var contentType = headers['content-type'];
    var linkElement = document.createElement('a');
    try {
        var blob = new Blob([data], { type: contentType });
        var url = window.URL.createObjectURL(blob);

        linkElement.setAttribute('href', url);
        linkElement.setAttribute("download", filename);

        var clickEvent = new MouseEvent("click", {
            "view": window,
            "bubbles": true,
            "cancelable": false
        });
        linkElement.dispatchEvent(clickEvent);
    } catch (ex) {
        console.log(ex);
    }
}).error(function (data, status, headers, config) {
}).finally(function () {

});

The following code worked for me

//Parameter to be passed
var data = 'reportid=R3823&isSQL=1&filter=[]';
var xhr = new XMLHttpRequest();
xhr.open("POST", "Reporting.jsp"); //url.It can pdf file path
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.responseType = "blob";
xhr.onload = function () {
    if (this.status === 200) {
        var blob = new Blob([xhr.response]);
        const url = window.URL.createObjectURL(blob);
        var a = document.createElement('a');
        a.href = url;
        a.download = 'myFile.pdf';
        a.click();
        setTimeout(function () {
            // For Firefox it is necessary to delay revoking the ObjectURL
            window.URL.revokeObjectURL(data)
                , 100
        })
    }
};
xhr.send(data);

Hope this will save you a few hours and spare you from a headache. It took me a while to figure this out, but doing regular $.ajax() request ruined my PDF file, while requesting it through address bar worked perfectly. Solution was this:

Include download.js: http://danml.com/download.html

Then use XMLHttpRequest instead of $.ajax() request.

    var ajax = new XMLHttpRequest(); 

    ajax.open("GET", '/Admin/GetPdf' + id, true); 
    ajax.onreadystatechange = function(data) { 
        if (this.readyState == 4)
        {
            if (this.status == 200)
            {
                download(this.response, "report.pdf", "application/pdf");

            }
            else if (this.responseText != "")
            {
                alert(this.responseText);
            }
        }
        else if (this.readyState == 2)
        {
            if (this.status == 200)
            {
                this.responseType = "blob";
            }
            else
            {
                this.responseType = "text";
            }
        }
    };

    ajax.send(null);

Concerning the answer given by Mayur Padshala this is the correct logic to download a pdf file via ajax but as others report in the comments this solution is indeed downloads a blank pdf.

The reason for this is explained in the accepted answer of this question: jQuery has some issues loading binary data using AJAX requests, as it does not yet implement some HTML5 XHR v2 capabilities, see this enhancement request and this discussion.

So using HTMLHTTPRequest the code should look like this:

var req = new XMLHttpRequest();
req.open("POST", "URL", true);
req.responseType = "blob";
req.onload = function (event) {
    var blob = req.response;
    var link=document.createElement('a');
    link.href=window.URL.createObjectURL(blob);
    link.download="name_for_the_file_to_save_with_extention";
    link.click();
}

This is how i solve this issue.
The answer of Jonathan Amend on this post helped me a lot.
The example below is simplified.

For more details, the above source code is able to download a file using a JQuery Ajax request (GET, POST, PUT etc). It, also, helps to upload parameters as JSON and to change the content type to application/json (my default).

The html source:

<form method="POST">
    <input type="text" name="startDate"/>
    <input type="text" name="endDate"/>
    <input type="text" name="startDate"/>
    <select name="reportTimeDetail">
        <option value="1">1</option>
    </select>
    <button type="submit"> Submit</button>
</form>  

A simple form with two input text, one select and a button element.

The javascript page source:

<script type="text/javascript" src="JQuery 1.11.0 link"></script>
<script type="text/javascript">
    // File Download on form submition.
    $(document).on("ready", function(){
        $("form button").on("click", function (event) {
            event.stopPropagation(); // Do not propagate the event.

            // Create an object that will manage to download the file.
            new AjaxDownloadFile({
                url: "url that returns a file",
                data: JSON.stringify($("form").serializeObject())
            });

            return false; // Do not submit the form.
        });
    });
</script>  

A simple event on button click. It creates an AjaxDownloadFile object. The AjaxDownloadFile class source is below.

The AjaxDownloadFile class source:

var AjaxDownloadFile = function (configurationSettings) {
    // Standard settings.
    this.settings = {
        // JQuery AJAX default attributes.
        url: "",
        type: "POST",
        headers: {
            "Content-Type": "application/json; charset=UTF-8"
        },
        data: {},
        // Custom events.
        onSuccessStart: function (response, status, xhr, self) {
        },
        onSuccessFinish: function (response, status, xhr, self, filename) {
        },
        onErrorOccured: function (response, status, xhr, self) {
        }
    };
    this.download = function () {
        var self = this;
        $.ajax({
            type: this.settings.type,
            url: this.settings.url,
            headers: this.settings.headers,
            data: this.settings.data,
            success: function (response, status, xhr) {
                // Start custom event.
                self.settings.onSuccessStart(response, status, xhr, self);

                // Check if a filename is existing on the response headers.
                var filename = "";
                var disposition = xhr.getResponseHeader("Content-Disposition");
                if (disposition && disposition.indexOf("attachment") !== -1) {
                    var filenameRegex = /filename[^;=\n]*=(([""]).*?\2|[^;\n]*)/;
                    var matches = filenameRegex.exec(disposition);
                    if (matches != null && matches[1])
                        filename = matches[1].replace(/[""]/g, "");
                }

                var type = xhr.getResponseHeader("Content-Type");
                var blob = new Blob([response], {type: type});

                if (typeof window.navigator.msSaveBlob !== "undefined") {
                    // IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed.
                    window.navigator.msSaveBlob(blob, filename);
                } else {
                    var URL = window.URL || window.webkitURL;
                    var downloadUrl = URL.createObjectURL(blob);

                    if (filename) {
                        // Use HTML5 a[download] attribute to specify filename.
                        var a = document.createElement("a");
                        // Safari doesn"t support this yet.
                        if (typeof a.download === "undefined") {
                            window.location = downloadUrl;
                        } else {
                            a.href = downloadUrl;
                            a.download = filename;
                            document.body.appendChild(a);
                            a.click();
                        }
                    } else {
                        window.location = downloadUrl;
                    }

                    setTimeout(function () {
                        URL.revokeObjectURL(downloadUrl);
                    }, 100); // Cleanup
                }

                // Final custom event.
                self.settings.onSuccessFinish(response, status, xhr, self, filename);
            },
            error: function (response, status, xhr) {
                // Custom event to handle the error.
                self.settings.onErrorOccured(response, status, xhr, self);
            }
        });
    };
    // Constructor.
    {
        // Merge settings.
        $.extend(this.settings, configurationSettings);
        // Make the request.
        this.download();
    }
};

I created this class to added to my JS library. It is reusable. Hope that helps.

I don't really think that any of the past answers spotted out the problem of the original poster. They all presume a GET request while the poster was trying to POST data and get a download in response.

In the course of searching for any better answer we found this jQuery Plugin for Requesting Ajax-like File Downloads.

In its "heart" it creates a "temporary" HTML form containing the given data as input fields. This form is appended to the document and posted to the desired URL. Right after that the form is removed again:

jQuery('<form action="'+ url +'" method="'+ (method||'post') +'">'+inputs+'</form>')
    .appendTo('body').submit().remove()

Update Mayur's answer looks pretty promising and very simple in comparison to the jQuery plug-in I referred to.

create a hidden iframe, then in your ajax code above:

url: document.getElementById('myiframeid').src = your_server_side_url,

and remove the window.open(response);

To fix the blank PDF issue in post request to get stream data like PDF, we need to add response type as 'arraybuffer' or 'blob' in request

$.ajax({
  url: '<URL>',
  type: "POST",
  dataType: 'arraybuffer',
  success: function(data) {
    let blob = new Blob([data], {type: 'arraybuffer'});
    let link = document.createElement('a');
    let objectURL = window.URL.createObjectURL(blob);
    link.href = objectURL;
    link.target = '_self';
    link.download = "fileName.pdf";
    (document.body || document.documentElement).appendChild(link);
    link.click();
    setTimeout(()=>{
        window.URL.revokeObjectURL(objectURL);
        link.remove();
    }, 100);
  }
});

If you have to work with file-stream (so no physically saved PDF) like we do and you want to download the PDF without page-reload, the following function works for us:

HTML

<div id="download-helper-hidden-container" style="display:none">
     <form id="download-helper-form" target="pdf-download-output" method="post">
            <input type="hidden" name="downloadHelperTransferData" id="downloadHelperTransferData" />
     </form>
     <iframe id="pdf-helper-output" name="pdf-download-output"></iframe>
</div>

Javascript

var form = document.getElementById('download-helper-form');
$("#downloadHelperTransferData").val(transferData);
form.action = "ServerSideFunctionWhichWritesPdfBytesToResponse";
form.submit();

Due to the target="pdf-download-output", the response is written into the iframe and therefore no page reload is executed, but the pdf-response-stream is output in the browser as a download.

Here is how I got this working

$.ajax({
  url: '<URL_TO_FILE>',
  success: function(data) {
    var blob=new Blob([data]);
    var link=document.createElement('a');
    link.href=window.URL.createObjectURL(blob);
    link.download="<FILENAME_TO_SAVE_WITH_EXTENSION>";
    link.click();
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

Updated answer using download.js

$.ajax({
  url: '<URL_TO_FILE>',
  success: download.bind(true, "<FILENAME_TO_SAVE_WITH_EXTENSION>", "<FILE_MIME_TYPE>")
});