What is connect-timeout?
The connect-timeout npm package is a middleware for Connect/Express applications that allows you to set a timeout for HTTP requests. If a request takes longer than the specified timeout, it will be aborted and a timeout error will be sent to the client.
What are connect-timeout's main functionalities?
Setting a basic timeout
This feature allows you to set a basic timeout for all incoming HTTP requests. If a request takes longer than the specified time (in this case, 5 seconds), it will be aborted and a timeout error will be sent to the client.
const express = require('express');
const timeout = require('connect-timeout');
const app = express();
// Set a timeout of 5 seconds
app.use(timeout('5s'));
app.get('/', (req, res) => {
// Simulate a long-running request
setTimeout(() => {
res.send('Hello, world!');
}, 6000);
});
app.use((err, req, res, next) => {
if (req.timedout) {
res.status(503).send('Service unavailable. Please try again later.');
} else {
next(err);
}
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Custom timeout handler
This feature allows you to define a custom timeout handler. If a request times out, the custom handler will send a specific message to the client.
const express = require('express');
const timeout = require('connect-timeout');
const app = express();
// Set a timeout of 5 seconds
app.use(timeout('5s'));
app.get('/', (req, res) => {
// Simulate a long-running request
setTimeout(() => {
res.send('Hello, world!');
}, 6000);
});
// Custom timeout handler
app.use((req, res, next) => {
if (req.timedout) {
res.status(503).send('Custom timeout message: Service unavailable.');
} else {
next();
}
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Conditional timeout
This feature allows you to set a conditional timeout based on the request path. In this example, the '/slow' endpoint has a longer timeout of 10 seconds, while other endpoints do not have a timeout.
const express = require('express');
const timeout = require('connect-timeout');
const app = express();
// Set a conditional timeout
app.use((req, res, next) => {
if (req.path === '/slow') {
timeout('10s')(req, res, next);
} else {
next();
}
});
app.get('/slow', (req, res) => {
// Simulate a long-running request
setTimeout(() => {
res.send('This is a slow endpoint.');
}, 11000);
});
app.get('/fast', (req, res) => {
res.send('This is a fast endpoint.');
});
app.use((err, req, res, next) => {
if (req.timedout) {
res.status(503).send('Service unavailable. Please try again later.');
} else {
next(err);
}
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Other packages similar to connect-timeout
express-timeout-handler
The express-timeout-handler package provides similar functionality to connect-timeout by allowing you to set timeouts for HTTP requests in Express applications. It also offers more advanced features such as custom error messages and different timeout strategies. Compared to connect-timeout, express-timeout-handler provides more flexibility and customization options.
express-timeout
The express-timeout package is another middleware for setting timeouts in Express applications. It is simpler and more lightweight compared to connect-timeout, making it a good choice for projects that require basic timeout functionality without additional features.
connect-timeout
![Gratipay](https://img.shields.io/gratipay/dougwilson.svg)
Times out a request in the Connect/Express application framework.
Install
This is a Node.js module available through the
npm registry. Installation is done using the
npm install
command:
$ npm install connect-timeout
API
NOTE This module is not recommend as a "top-level" middleware (i.e.
app.use(timeout('5s'))
) unless you take precautions to halt your own
middleware processing. See as top-level middleware
for how to use as a top-level middleware.
While the library will emit a 'timeout' event when requests exceed the given
timeout, node will continue processing the slow request until it terminates.
Slow requests will continue to use CPU and memory, even if you are returning
a HTTP response in the timeout callback. For better control over CPU/memory,
you may need to find the events that are taking a long time (3rd party HTTP
requests, disk I/O, database calls) and find a way to cancel them, and/or
close the attached sockets.
timeout(time, [options])
Returns middleware that times out in time
milliseconds. time
can also
be a string accepted by the ms
module. On timeout, req
will emit "timeout"
.
Options
The timeout
function takes an optional options
object that may contain
any of the following keys:
respond
Controls if this module will "respond" in the form of forwarding an error.
If true
, the timeout error is passed to next()
so that you may customize
the response behavior. This error has a .timeout
property as well as
.status == 503
. This defaults to true
.
req.clearTimeout()
Clears the timeout on the request. The timeout is completely removed and
will not fire for this request in the future.
req.timedout
true
if timeout fired; false
otherwise.
Examples
as top-level middleware
Because of the way middleware processing works, once this module
passes the request to the next middleware (which it has to do in order
for you to do work), it can no longer stop the flow, so you must take
care to check if the request has timedout before you continue to act
on the request.
var bodyParser = require('body-parser')
var cookieParser = require('cookie-parser')
var express = require('express')
var timeout = require('connect-timeout')
var app = express()
app.use(timeout('5s'))
app.use(bodyParser())
app.use(haltOnTimedout)
app.use(cookieParser())
app.use(haltOnTimedout)
function haltOnTimedout (req, res, next) {
if (!req.timedout) next()
}
app.listen(3000)
express 3.x
var express = require('express')
var bodyParser = require('body-parser')
var timeout = require('connect-timeout')
var app = express()
app.post('/save', timeout('5s'), bodyParser.json(), haltOnTimedout, function (req, res, next) {
savePost(req.body, function (err, id) {
if (err) return next(err)
if (req.timedout) return
res.send('saved as id ' + id)
})
})
function haltOnTimedout (req, res, next) {
if (!req.timedout) next()
}
function savePost (post, cb) {
setTimeout(function () {
cb(null, ((Math.random() * 40000) >>> 0))
}, (Math.random() * 7000) >>> 0)
}
app.listen(3000)
connect
var bodyParser = require('body-parser')
var connect = require('connect')
var timeout = require('connect-timeout')
var app = connect()
app.use('/save', timeout('5s'), bodyParser.json(), haltOnTimedout, function (req, res, next) {
savePost(req.body, function (err, id) {
if (err) return next(err)
if (req.timedout) return
res.send('saved as id ' + id)
})
})
function haltOnTimedout (req, res, next) {
if (!req.timedout) next()
}
function savePost (post, cb) {
setTimeout(function () {
cb(null, ((Math.random() * 40000) >>> 0))
}, (Math.random() * 7000) >>> 0)
}
app.listen(3000)
License
MIT