Express REST API

code 102 notes

Express REST API

Name 3 real world use cases where you’d want to change the request with custom middleware

  1. error handlers

  2. print message

  3. request timestamp

True or false: The route handler is middleware?

False

In what ways can a middleware function end the process and send data to the browser?

  • next(), response.send; .status, .end

At what point in the request lifecycle can you “inject” middleware?

Between the method and the path

What can cause express to error with “Request headers sent twice, cannot start a second response”

  • Another function tried to set a header or status code.

  • You are already in the Body or Finished state.

  • A callback may have accidentally been called twice.

Document the following Vocabulary Terms

Middleware

Functions that exist between the method and the path

Request Object

An object that contains the data sent to the server within an HTTP request

Response Object

An object which contains the data the server sends back after receiving a request

Application Middleware

Called with app.use()

Routing Middleware

Bound to an instance of express.Router()

Test Driven Development

A programming style involving coding, testing, and design/refactoring