Create a test suite

Create a test suite using the mocha APIs for the project to facilitate the following:

• Add firestore config for test or use any firestore mocking libraries(if available), and thus remove all model function mocks ✅
  • https://firebase.google.com/docs/emulator-suite
  • https://stackoverflow.com/questions/46563885/running-firestore-local-e-g-for-testing
• Define custom test specific config.
  • Be able to define custom config for tests to achieve https://github.com/Real-Dev-Squad/website-backend/blob/develop/middlewares/authenticate.js#L14
• Reduce redundancy in each test files ✅
  • Use Mocha API https://mochajs.org/api/mocha to start the test suite and define globals
  • Start the server only once rather than passing the server.js to chai HTTP module
• Mocking XHR calls ✅
• Mocking function calls ✅
• Test coverage in the repo ✅

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Current issues in test suite:

• firebase emulators:start (code) is a blocking process and does not get terminates after the test process gets finished. ✅
• Create an interface/utility to flush the DB. It can be used in the mocha tests as per required.
• Define custom test specific config.
  • Be able to define custom config for tests to achieve https://github.com/Real-Dev-Squad/website-backend/blob/develop/middlewares/authenticate.js#L14