POST /api/v1/users

In this book, we go with the first approach to the POST method. So, let's define our route for the post method in app.py, and call the function to update the user record to the database file, as follows:

    @app.route('/api/v1/users', methods=['POST']) 
    def create_user(): 
      if not request.json or not 'username' in request.json or not
      'email' in request.json or not 'password' in request.json: 
        abort(400) 
     user = { 
        'username': request.json['username'], 
        'email': request.json['email'], 
        'name': request.json.get('name',""), 
        'password': request.json['password'] 
     } 
      return jsonify({'status': add_user(user)}), 201 

As you can see, in the preceding method, we called the exception with error code 400; let's write its handler now:

    @app.errorhandler(400) 
    def invalid_request(error): 
       return make_response(jsonify({'error': 'Bad Request'}), 400) 

We still need to define the add_user(user) function, which will update the new user record. Let's define it in app.py, as follows:

    def add_user(new_user): 
     conn = sqlite3.connect('mydb.db') 
     print ("Opened database successfully"); 
     api_list=[] 
     cursor=conn.cursor() 
     cursor.execute("SELECT * from users where username=? or
      emailid=?",(new_user['username'],new_user['email'])) 
    data = cursor.fetchall() 
    if len(data) != 0: 
        abort(409) 
    else: 
       cursor.execute("insert into users (username, emailid, password,
   full_name) values(?,?,?,?)",(new_user['username'],new_user['email'],
    new_user['password'], new_user['name'])) 
       conn.commit() 
       return "Success" 
    conn.close() 
    return jsonify(a_dict) 

Now that we have added handler, as well as the route for the POST method of the user, let's test it by adding a new user using the following API call:

curl -i -H "Content-Type: application/json" -X POST -d '{
"username":"mahesh@rocks", "email": "mahesh99@gmail.com",
"password": "mahesh123", "name":"Mahesh" }' 
http://localhost:5000/api/v1/users

Then, validate the user's list curl, http://localhost:5000/api/v1/users, as shown in the following screenshot: