Flask example with POST

Question

Suppose the following route which accesses an xml file to replace the text of a specific tag with a given xpath   key      app route   resource   methods     POST    def update text          CODE   Then  I would use cURL like this   curl -X POST http   ip 5000 resource key listOfUsers user1 -d  John    The xpath expreesion listOfUsers user1 should access the tag  lt user1 gt  to change its current text to  John    I have no idea on how to achieve this because I m just starting to learn Flask and REST and I can t find any good example for this specific case  Also  I d like to use lxml to manipulate the xml file since I already know it    Could somebody help and provide an example to guide me

User · Answer

Here is the example in which you can easily find the way to use Post GET method and use the same way to add other curd operations as well     libraries to include  import os from flask import request  jsonify from app import app  mongo import logger ROOT PATH   os environ get  ROOT PATH   lt br gt   app route   get questions    methods   GET    POST   DELETE    PATCH        def question          request args is to get urls arguments        if request method     GET           start   request args get  start   default 0  type int          limit url   request args get  limit   default 20  type int          questions   mongo db questions find   limit limit url  skip start           data    doc for doc in questions          return jsonify isError  False                      message   Success                       statusCode  200                      data  data   200    request form to get form parameter      if request method     POST           average time   request form get  average time           choices   request form get  choices           created by   request form get  created by           difficulty level   request form get  difficulty level           question   request form get  question           topics   request form get  topics          Do something like insert in DB or Render somewhere etc  it s up to you

User · Answer

Before actually answering your question   Parameters in a URL  e g  key listOfUsers user1  are GET parameters and you shouldn t be using them for POST requests  A quick explanation of the difference between GET and POST can be found here   In your case  to make use of REST principles  you should probably have   http   ip 5000 users http   ip 5000 users  lt user id gt    Then  on each URL  you can define the behaviour of different HTTP methods  GET  POST  PUT  DELETE   For example  on  users  lt user id gt   you want the following   GET  users  lt user id gt  - return the information for  lt user id gt  POST  users  lt user id gt  - modify update the information for  lt user id gt  by providing the data PUT - I will omit this for now as it is similar enough to  POST  at this level of depth DELETE  users  lt user id gt  - delete user with ID  lt user id gt     So  in your example  you want do a POST to  users user 1 with the POST data being  John   Then the XPath expression or whatever other way you want to access your data should be hidden from the user and not tightly couple to the URL  This way  if you decide to change the way you store and access data  instead of all your URL s changing  you will simply have to change the code on the server-side   Now  the answer to your question  Below is a basic semi-pseudocode of how you can achieve what I mentioned above   from flask import Flask from flask import request  app   Flask   name      app route   users  lt user id gt    methods     GET    POST    DELETE    def user user id       if request method     GET              return the information for  lt user id gt                                       if request method     POST              modify update the information for  lt user id gt               you can use  lt user id gt   which is a str but could           changed to be int or whatever you want  along           with your lxml knowledge to make the required           changes         data   request form   a multidict containing POST data                                   if request method     DELETE              delete user with ID  lt user id gt                                       else            POST Error 405 Method Not Allowed                                 There are a lot of other things to consider like the POST request content-type but I think what I ve said so far should be a reasonable starting point  I know I haven t directly answered the exact question you were asking but I hope this helps you  I will make some edits additions later as well   Thanks and I hope this is helpful  Please do let me know if I have gotten something wrong

[python] Flask example with POST

Examples related to python

Examples related to rest

Examples related to flask

Examples related to lxml