API without authentication

  from flask import Flask jsonify

  app = flask( _name_ )

  @app.route('/hello', methods = ['GET'])
   def hello _ world():

        return jsonify({"message":"Hello.world!"})
  
   if_name_=="_main_";

      app.run(debug=True)

1 Importing Flask and JSON Response Function

from flask import Flask jsonify

   flask: is framework, help to build the web application and API


   jsonify: This is used to convert python data(like dictionaries) into JSON format which is the format APIs us to send data

2 Creating the Flask app

 app = flask( _name_ )
 
 flask( _name_ ): it creates  a flask application object. the _name_ variable tells  to flask that this is main file where  app is defined

3 Defining API endpoint

   @app.route('/hello', methods = ['GET'])
    def hello _ world():

     return jsonify({"message":"Hello.world!"})
     
     1. set up URL endpoint /hello.

       methods = ['GET'] this endpoint  only accept GET request(used for retrieving data)


     2.  hello _ world():

     this function will run when someone accesses the /hello endpoint.

     3.  return jsonify({"message":"Hello.world!"})

     It returns a JSON response with the message

4 Running Flask App

 if_name_=="_main_";

      app.run(debug=True)

  1. this checks if the script is being run directly (not imported from another file)


  2. second line the flask development server

   debug=True, this one allows automatic reloading when we make code changes and shows errors in the browser.