Serverless TODO social network

• In this capstone project, I inherited from course-4 serverless TODO project, and extended with social network functionalitiy
  • able to follow other users.
  • able to see newsfeed (actually TodosFeed: followees's TODOs).
  • follower will be notified when someone followed you.
  • able to comment on others todos.
• I implemented in backend, and tested in postman. Please check the postman-collection file: Cloud-Dev Capstone.postman_collection.json to test.

Issues

Websockets

• There is a different mechanism than the standard HTTP headers; some abstraction layers implement a similar strategy. So I ported original HTTP's authorizer: backend/src/lambda/auth/auth0Authorizer.ts to handle Websocket authorization.

• for connection URL, I have to give speicific permission in the sendNotification function: execute-api:ManageConnections, so as to allow websocket operations: POST, DELETE and GET.

• I noticed one weird issue: some functions always got internal server error in 20 min. And I got them available later with any actions. But I only encountered this twice till now (30 deploys)

  • just encountered again when upload image. No log in GenerateUploadUrl. I'm able to upload 2 min later.
  • I guess the issue is with cold-start, since all functions are same size: 22.1MB! So I package individually to downsize to less than 2MB

Screenshots

• Notify followee, once someone followed him/her, while followee is connected with websocket.

• Create a new todo from UI

• upload Image todo in UI

• login with another gmail account in UI

• auth0 login page in ui

• create new Follow

• create new comment

• get all Todos

• get newsFeed