Simple REST Server Integration test

[anu1667]

Simple REST Server Integration test

Add test code to the previous code.

• Use jest module

• Execute the test after running the web api server in the terminal

Test’s requirement:

Regarding web server when doing GET, confirming that answer:0 is returned.

Regarding web server when doing POST, confirming that the result of the multiplication is returned.

[Eshwari247]

References - https://alemser.medium.com/integration-tests-an-approach-for-the-rest-api-ae86e47b7b43 https://circleci.com/blog/api-testing-with-jest/

• Jest provides comprehensive testing environment, allows to write unit tests, integration tests, and end-to-end tests
• Jest integrates well with popular CI/CD tools like Jenkins, Travis CI, and GitHub Actions, allows to run tests automatically in your CI pipeline
• Jest comes with many built-in features, including mocking, asynchronous testing, assertions
• Jest is primarily for testing JavaScript code, while Express is a framework for building web applications and APIs

[Eshwari247]

How to run a RESTApi tests via Jest -

• Set Up Project, express is for building the API, jest is for writing and running tests, and supertest is for making HTTP requests to API during testing.
• Configure jest - node environment
• Create Express API (app.js)
• Write tests, import app.js
• Run tests via npx jest

[Eshwari247]

• Problem faced running both express api and test in file Describe function running on node

• Fixes Run the files separately Node doesn't support Describe

• Tip Use try and catch methods to find errors for line -to -line checks

[anu1667]

• Add required packages in package.json - express, supertest
• You can commit package-lock.json to the repository. We can use npm ci to install packages. More explanation can be found here - https://stackoverflow.com/questions/52499617/what-is-the-difference-between-npm-install-and-npm-ci.

Test

ananditabendigeri@Ananditas-MacBook-Pro  ~/init_exercises/EX5   main ±  npm test

> package@1.0.0 test
> jest

  console.log
    Server is running on http://localhost:8080

      at Server.log (app.js:24:13)

 PASS  ./api.test.js
  GET /cal
    ✓ should return 0 (21 ms)
  POST /cal
    ✓ should return the result of multiplication (7 ms)

Test Suites: 1 passed, 1 total
Tests:       2 passed, 2 total
Snapshots:   0 total
Time:        0.343 s
Ran all test suites.
Jest did not exit one second after the test run has completed.

'This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with `--detectOpenHandles` to troubleshoot this issue.
^C

At the end of jest test I receive this warning - This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with--detectOpenHandlesto troubleshoot this issue.

Reason - The server doesn't close/stop listening after end of tests Solution - Try to start express server in test file itself and close after test. Something like this

beforeAll(() => {
      //server start
});

afterAll(() => {
    //server close
});