# Connecting through a proxy
Connecting through a proxy is possible by:
- Using [AgentProxy](../api/ProxyAgent.md).
- Configuring `Client` or `Pool` constructor.
The proxy url should be passed to the `Client` or `Pool` constructor, while the upstream server url
should be added to every request call in the `path`.
For instance, if you need to send a request to the `/hello` route of your upstream server,
the `path` should be `path: 'http://upstream.server:port/hello?foo=bar'`.
If you proxy requires basic authentication, you can send it via the `proxy-authorization` header.
### Connect without authentication
```js
import { Client } from 'undici'
import { createServer } from 'http'
import proxy from 'proxy'
const server = await buildServer()
const proxyServer = await buildProxy()
const serverUrl = `http://localhost:${server.address().port}`
const proxyUrl = `http://localhost:${proxyServer.address().port}`
server.on('request', (req, res) => {
console.log(req.url) // '/hello?foo=bar'
res.setHeader('content-type', 'application/json')
res.end(JSON.stringify({ hello: 'world' }))
})
const client = new Client(proxyUrl)
const response = await client.request({
method: 'GET',
path: serverUrl + '/hello?foo=bar'
})
response.body.setEncoding('utf8')
let data = ''
for await (const chunk of response.body) {
data += chunk
}
console.log(response.statusCode) // 200
console.log(JSON.parse(data)) // { hello: 'world' }
server.close()
proxyServer.close()
client.close()
function buildServer () {
return new Promise((resolve, reject) => {
const server = createServer()
server.listen(0, () => resolve(server))
})
}
function buildProxy () {
return new Promise((resolve, reject) => {
const server = proxy(createServer())
server.listen(0, () => resolve(server))
})
}
```
### Connect with authentication
```js
import { Client } from 'undici'
import { createServer } from 'http'
import proxy from 'proxy'
const server = await buildServer()
const proxyServer = await buildProxy()
const serverUrl = `http://localhost:${server.address().port}`
const proxyUrl = `http://localhost:${proxyServer.address().port}`
proxyServer.authenticate = function (req, fn) {
fn(null, req.headers['proxy-authorization'] === `Basic ${Buffer.from('user:pass').toString('base64')}`)
}
server.on('request', (req, res) => {
console.log(req.url) // '/hello?foo=bar'
res.setHeader('content-type', 'application/json')
res.end(JSON.stringify({ hello: 'world' }))
})
const client = new Client(proxyUrl)
const response = await client.request({
method: 'GET',
path: serverUrl + '/hello?foo=bar',
headers: {
'proxy-authorization': `Basic ${Buffer.from('user:pass').toString('base64')}`
}
})
response.body.setEncoding('utf8')
let data = ''
for await (const chunk of response.body) {
data += chunk
}
console.log(response.statusCode) // 200
console.log(JSON.parse(data)) // { hello: 'world' }
server.close()
proxyServer.close()
client.close()
function buildServer () {
return new Promise((resolve, reject) => {
const server = createServer()
server.listen(0, () => resolve(server))
})
}
function buildProxy () {
return new Promise((resolve, reject) => {
const server = proxy(createServer())
server.listen(0, () => resolve(server))
})
}
```
