Express·Express essentials

JSON APIs

Read request bodies and return consistent JSON responses.

Beginner 10 min read Lesson 3 of 150 Challenge included
What you will be able to do
  • Use req.body after express.json().
  • Validate input.
  • Set status codes.

In plain English

Read request bodies and return consistent JSON responses.

  • Use req.body after express.json().
  • Validate input.
  • Set status codes.
api.jsJavaScript
app.post('/api/courses', (req, res) => {
  const { title } = req.body
  if (!title) return res.status(422).json({ error: 'title required' })
  res.status(201).json({ slug: title.toLowerCase(), title })
})
Your turn

Explain it back

Easy

Answer from memory: Which status code means created?

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

Which status code means created?

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Lesson 3 of 150 · 0% of course