Express - lesson 4 | HackIndia Skills

Express - lesson 4 | HackIndia Skills | HackIndia

Example

One projects route

This example reads all three places. It creates a project from the JSON body, uses the path param for the owner, and reads an optional query flag.

Keep validation simple here. Later lessons can improve errors and status codes.

import express from 'express';

const app = express();

app.use(express.json());

app.get('/projects/:projectId', (req, res) => {
  const { projectId } = req.params;
  const { includeTeam } = req.query;

  res.json({
    projectId,
    includeTeam: includeTeam === 'true'
  });
});

app.post('/students/:studentId/projects', (req, res) => {
  const { studentId } = req.params;
  const { title, repoUrl } = req.body ?? {};
  const { source } = req.query;

  res.json({
    message: 'Project received',
    studentId,
    source: source ?? 'direct',
    project: {
      title,
      repoUrl
    }
  });
});

app.listen(3000, () => {
  console.log('API running on http://localhost:3000');
});

Your to-do

Test with curl

Do each one yourself, then tap it to tick it off. The ticks are only a checklist for you: they are not marked or scored.

Start your server from the terminal.
Send a GET request with a route param and query string.
Send a POST request with a JSON body.
Check that each value appears in the response.
Change one value at a time to confirm where it comes from.

0 of 5 done

curl "http://localhost:3000/projects/42?includeTeam=true"

curl -X POST "http://localhost:3000/students/s101/projects?source=hackindia" \
  -H "Content-Type: application/json" \
  -d '{"title":"UPI Expense Tracker","repoUrl":"https://github.com/you/upi-expense-tracker"}'

Read Bodies, Queries, and Params

Three input places

Params are path values

Queries are filters

Body is not automatic

One projects route

Test with curl

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