How To Process Incoming Request Data in Flask

In this article, we will learn how we can use the request object in a flask to process Incoming request data that is passed to your routes and How To Process incoming Request Data in Flask using Python. Flask has some functionality like tools, libraries, and technologies that allow you to build a web application, and Web applications frequently require processing incoming Data requests from users.

Process Incoming Request Data in Flask

To perform Process Incoming Request Data in a Flask Application we will use some request properties that received the data in an efficient way, for that we will create the routes and call the requested property.

• Accesses the Query String
• Accesses the Form Data.
• Returned the JSON data.

Accesses the Query String Parameter

So start with the Request object the thing is that you know about the Request object that contains everything incoming into your endpoint. so basically it contains the incoming data, referrer, IP Address, raw data, and HTTP method and also contains a header.

Step 1: So, firstly we will import the Flask module that is essential for completion to process incoming request data. Now we call the Flask-Application flask constructor call the name of the current module (__name__) as an argument.

Python3

from flask import Flask, request
app = Flask(__name__)

Step 2: Now we’ll just modify the line of code and going to allow the route to read in any of the query parameters, for that use the request object and call the args.get and pass get. we will make an HTML header tag.

Python3

# code
from flask import Flask,request
@app.route('/query_example')
def query_example():
    language =  request.args.get('language')
    return '<h1> The Language is : {GeeksForGeeks} </h1>'.format(language)
if __name__ == '__main__':
    app.run(debug=True, port=5000)

Output:

http://127.0.0.1:5000/query_example?language=python

Create the key ‘language’ and value as ‘python’

Step 3: Now just implement the code in the query_example() function

Python3

# code
def query_example():
    language =  request.args.get('language')
    framework = request.args['framework']
    website = request.args.get('website')
    return '''<h1> The Language is : {} </h1>
              <h1> The framework is : {} </h1>
              <h1> The website is : {}  </h1>'''
                  .format(language,framework, website)

Output:

http://127.0.0.1:5000/query_example?language=PHP&framework=Flask&website=flask.org

Create a key ‘framework’ & ‘website’ and their value as ‘Flask’ & ‘flask.org’

Accesses the Form Data

Step 1: Now we will use the form example here with the POST method and create the web form on a browser, for performing that we need to create a route and function. And remaining code as it is the same, following the line of code.

Python3

# create route for form and function.
@app.route('/form_example')
def form_example():
    return '''<form method="POST" action="">
    Language <input types="text" name="language">
    Framework <input type="text" name="framework">
    <input type="submit">
    </form>'''

Output:

http://127.0.0.1:5000/form_example

Step 2:  So let’s fill the form in the language we write Python and in the framework, by submitting the form we are able to read the foreign data in post request and display it to the user. Now we will use the POST and GET methods as well as conditions, to show the language and which framework we are using.

Python3

# use the POST and GET method for creative form.
@app.route('/form_example', methods=['POST', 'GET'])
def form_example():
    if request.method == 'POST':
        language = request.form.get('language')
        framework = request.form['framework']
        return
      '<h1> The language is {}.\
      The framework is {}.</h1>'.format(language, framework)
    return '''<form method="POST" action="">
    Language <input types="text" name="language">
    Framework <input type="text" name="framework">
    <input type="submit">
    </form>'''

Output:

Accesses the JSON Data

Step 1: Now we take the JSON data which is normally constructed by a process that calls the route. 

Python3

# create the route for call JSON Data
@app.route('/json_example')
def json_example():
    return 'Hey GeeksForGeeks'

Output:

http://127.0.0.1:5000/json_example

Step 2: Now for performing the JSON data we need the tool ‘Postman’ which performance is automated. After then you have to just copy the browser JSON data link and paste it into postman.

Step 3: Now, we will sync some data over to Flask through Postman, change the data to row and change the type to JSON application after then we will create a JSON object in postman.

{
   “language” : “Python”,
   “framework” : “Flask”,
   “website” : “scotch”,
   “version_info” : {
       “python” : 3.7,
       “flask” : 1.0
   },
   “example” : [ “query”, “form”, “json”],
   “boolean_test” : true
}

Step 4: Now here we will implement the JSON code and add all the JSON Object code in the Python file.

Python3

# code
@app.route('/json_example', methods=['POST'])
def json_example():
    req_data = request.get_json()

    language = req_data['language']
    framework = req_data['framework']
    python_version = req_data['version_info']['python']
    example = req_data['example'][0]
    boolean_test = req_data['boolean_test']

    return '''<h1>
    The language value is {}.
    The framework value is {}.
    The python version is {}.
    The example at 0 index is {}.
    The boolean value is {}.
    </h1>'''.format(language, framework, python_version, example, boolean_test)

Output: