Express·Express essentials

Middleware

Middleware runs in order and can read, modify or end the request.

Beginner 10 min read Lesson 2 of 150 Challenge included
What you will be able to do
  • Use app.use.
  • Call next() to continue.
  • Parse JSON with express.json().

In plain English

Middleware runs in order and can read, modify or end the request.

  • Use app.use.
  • Call next() to continue.
  • Parse JSON with express.json().
middleware.jsJavaScript
app.use(express.json())
app.use((req, res, next) => {
  console.log(req.method, req.url)
  next()
})
Your turn

Explain it back

Easy

Answer from memory: What must middleware call to continue?

TEXT · starter
Your answer…
Check your understanding before moving on.
Knowledge checkQuestion 1

What must middleware call to continue?

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Lesson 2 of 150 · 0% of course