Example 1: express request path
// GET 'http://www.example.com/admin/new?a=b'
app.get('/admin', (req, res, next) => {
req.originalUrl; // '/admin/new?a=b' (full path with query string)
req.baseUrl; // '/admin'
req.path; // '/new'
req.baseUrl + req.path; // '/admin/new' (full path without query string)
});
Example 2: express redirect
res.redirect('/foo/bar')
res.redirect('http://example.com')
res.redirect(301, 'http://example.com')
res.redirect('../login')
Example 3: app.get
const express = require('express');
const app = express();
const { getElementById, getIndexById, updateElement,
seedElements, createElement } = require('./utils');
const PORT = process.env.PORT || 4001;
// Use static server to serve the Express Yourself Website
app.use(express.static('public'));
const expressions = [];
seedElements(expressions, 'expressions');
const animals = [];
seedElements(animals, 'animals');
// Get all expressions
app.get('/expressions', (req, res, next) => {
res.send(expressions);
});
// Get a single expression
app.get('/expressions/:id', (req, res, next) => {
const foundExpression = getElementById(req.params.id, expressions);
if (foundExpression) {
res.send(foundExpression);
} else {
res.status(404).send();
}
});
// Update an expression
app.put('/expressions/:id', (req, res, next) => {
const expressionIndex = getIndexById(req.params.id, expressions);
if (expressionIndex !== -1) {
updateElement(req.params.id, req.query, expressions);
res.send(expressions[expressionIndex]);
} else {
res.status(404).send();
}
});
// Create an expression
app.post('/expressions', (req, res, next) => {
const receivedExpression = createElement('expressions', req.query);
if (receivedExpression) {
expressions.push(receivedExpression);
res.status(201).send(receivedExpression);
} else {
res.status(400).send();
}
});
// Delete an expression
app.delete('/expressions/:id', (req, res, next) => {
const expressionIndex = getIndexById(req.params.id, expressions);
if (expressionIndex !== -1) {
expressions.splice(expressionIndex, 1);
res.status(204).send();
} else {
res.status(404).send();
}
});
// Get all animals
app.get('/animals', (req, res, next) => {
res.send(animals);
});
// Get a single animal
app.get('/animals/:id', (req, res, next) => {
const animal = getElementById(req.params.id, animals);
if (animal) {
res.send(animal);
} else {
res.status(404).send();
}
});
// Create an animal
app.post('/animals', (req, res, next) => {
const receivedAnimal = createElement('animals', req.query);
if (receivedAnimal) {
animals.push(receivedAnimal);
res.status(201).send(receivedAnimal);
} else {
res.status(400).send();
}
});
// Update an animal
app.put('/animals/:id', (req, res, next) => {
const animalIndex = getIndexById(req.params.id, animals);
if (animalIndex !== -1) {
updateElement(req.params.id, req.query, animals);
res.send(animals[animalIndex]);
} else {
res.status(404).send();
}
});
// Delete a single animal
app.delete('/animals/:id', (req, res, next) => {
const animalIndex = getIndexById(req.params.id, animals);
if (animalIndex !== -1) {
animals.splice(animalIndex, 1);
res.status(204).send();
} else {
res.status(404).send();
}
});
app.listen(PORT, () => {
console.log(`Server is listening on ${PORT}`);
});
Example 4: http header express
app.get('/', (req, res) => {
req.header('User-Agent')
})
// Use the Request.header() method to access
//one individual request header’s value
Example 5: node js http request express
npm install [email protected]
Example 6: express render
// send the rendered view to the client
res.render('index')
// if a callback is specified, the rendered HTML string has to be sent explicitly
res.render('index', function (err, html) {
res.send(html)
})
// pass a local variable to the view
res.render('user', { name: 'Tobi' }, function (err, html) {
// ...
})