A Mini-Microservices App

02. Project Setup

$ npm install -g nodemon

$ cd app

$ npx create-react-app client

$ cd app

$ mkdir posts
$ cd posts
$ npm init -y

$ npm install --save express cors axios

$ cd app

$ mkdir comments
$ cd comments
$ npm init -y

$ npm install --save express cors axios

03. Posts Service Creation

$ cd posts
$ npm run start

04. Testing the Posts Service

$ curl \
--request POST http://localhost:4000/posts/ \
--header "Content-Type: application/json" \
| python -m json.tool

$ curl \
--request GET http://localhost:4000/posts/ \
--header "Content-Type: application/json" \
| python -m json.tool

05. Implementing a Comments Service

$ echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

to solve issue:

[nodemon] Internal watch failed: ENOSPC: System limit for number of file watchers reached, watch ***

$ cd comments
$ npm run start

06. Quick Comments Test

$ curl \
--data '{"content":"I am a comment"}' \
--header "Content-Type: application/json" \
--request POST http://localhost:4001/posts/123/comments \
| python -m json.tool

$ curl \
--request GET http://localhost:4001/posts/123/comments \
--header "Content-Type: application/json" \
| python -m json.tool

08. React Project Setup

$ cd client

$ npm install --save axios
$ npm start

09. Building Post Submission

10. Handling CORS Errors

11. Fetching and Rendering Posts

12. Creating Comments

13. Displaying Comments

15. Request Minimization Strategies

16. An Async Solution

17. Common Questions Around Async Events

18. Event Bus Overview

19. A Basic Event Bus Implementation

$ cd app
$ mkdir event-bus
$ cd event-bus

$ npm init -y
$ npm install --save express axios

$ npm run start

20. Emitting Events

21. Emitting Comment Creation Events

22. Receiving Events

23. Creating the Data Query Service

$ cd app
$ mkdir query
$ cd query

$ npm init -y
$ npm install --save express cors axios

$ npm run start

24. Parsing Incoming Events

25. Using the Query Service

26. Adding a Simple Feature

27. Issues with Comment Filtering

28. A Second Approach

29. How to Handle Resource Updates

30. Creating the Moderation Service

$ cd app
$ mkdir moderation
$ cd moderation

$ npm init -y
$ npm install --save express axios

$ npm run start

31. Adding Comment Moderation

32. Handling Moderation

33. Updating Comment Content

34. A Quick Test

Comment with text 'orange' has status 'rejected'.

35. Rendering Comments by Status

36. Dealing with Missing Events

37. Implementing Event Sync

38. Event Syncing in Action

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