How to deploy websocket on AWS ElasticBeanstalk?

How to deploy websocket on AWS ElasticBeanstalk?

Environment

• Python 3.7 EB platform version 3.1.5
• Flask 1.1.2

Solution

1. Save following code as application.py

   from flask import Flask, render_template
   from flask_sockets import Sockets
   
   app = Flask(__name__)
   app.debug = True
   
   sockets = Sockets(app)
   
   @sockets.route('/echo')
   def echo_socket(ws):
       while True:
           message = ws.receive()
           ws.send("I am Server")
   
   @app.route('/')
   def hello():
       return 'Hello World!'
   
   @app.route('/echo_test', methods=['GET'])
   def echo_test():
       return render_template('echo_test.html')
   
   # if __name__ == '__main__':
   #    app.run()
   

2. Save following code as Procfile.

   web: gunicorn --bind :8000 --workers 3 --threads 2 application:app -k flask_sockets.worker
   

3. Save python packages dependencies to requirements.txt

   pip freeze > requirements.txt
   
   # the Flask version I am using
   cffi==1.14.4
   click==7.1.2
   Flask==1.1.2
   Flask-Sockets==0.2.1
   greenlet==1.0.0
   itsdangerous==1.1.0
   Jinja2==2.11.2
   MarkupSafe==1.1.1
   pycparser==2.20
   six==1.15.0
   websocket-client==0.57.0
   Werkzeug==1.0.1
   zope.event==4.5.0
   zope.interface==5.2.0
   

4. Compress files into *.zip

   zip -r mywebsocket.zip .
   

5. Upload the file to AWS EB environment.

6. run following code for testing.

   from websocket import create_connection
   
   
   def client_handle():
       ws = create_connection('ws://EB_URL/echo')
       while True:
           if ws.connected:
               ws.send('hi,i am ws client')
               result = ws.recv()
               print(f"client received:{result}")
               ws.close()
   
   
   if __name__ == "__main__":
       client_handle()
   

7. Output

   python client.py
   client received:I am Server