Testing POST /todos

In this section, you're going to learn how to set up the test suite for the Todo API, similar to what we did in the test section, and we'll be writing two test cases for /todos. We're going to verify that when we send the correct data as the body, we get a 200 back with the completed doc, including the ID; and, if we send bad data, we expect a 400 back with the error object.

Installing npm modules for testing POST /todos route

Now before we can do any of this, we have to install all of those modules we installed in the test section, expect for assertions, mocha for the entire test suite, supertest to test our Express routes, and nodemon. The nodemon module is going to let us create that...