How to programmatically send a 404 response with Express/Node?
Javascriptnode.jsExpressHttp Status-CodesJavascript Problem Overview
I want to simulate a 404 error on my Express/Node server. How can I do that?
Javascript Solutions
Solution 1 - Javascript
Since Express 4.0, there's a dedicated sendStatus
function:
res.sendStatus(404);
If you're using an earlier version of Express, use the status
function instead.
res.status(404).send('Not found');
Solution 2 - Javascript
Updated Answer for Express 4.x
Rather than using res.send(404)
as in old versions of Express, the new method is:
res.sendStatus(404);
Express will send a very basic 404 response with "Not Found" text:
HTTP/1.1 404 Not Found
X-Powered-By: Express
Vary: Origin
Content-Type: text/plain; charset=utf-8
Content-Length: 9
ETag: W/"9-nR6tc+Z4+i9RpwqTOwvwFw"
Date: Fri, 23 Oct 2015 20:08:19 GMT
Connection: keep-alive
Not Found
Solution 3 - Javascript
You don't have to simulate it. The second argument to res.send
I believe is the status code. Just pass 404 to that argument.
Let me clarify that: Per the documentation on expressjs.org it seems as though any number passed to res.send()
will be interpreted as the status code. So technically you could get away with:
res.send(404);
Edit: My bad, I meant res
instead of req
. It should be called on the response
Edit: As of Express 4, the send(status)
method has been deprecated. If you're using Express 4 or later, use: res.sendStatus(404)
instead. (Thanks @badcc for the tip in the comments)
Solution 4 - Javascript
According to the site I'll post below, it's all how you set up your server. One example they show is this:
var http = require("http");
var url = require("url");
function start(route, handle) {
function onRequest(request, response) {
var pathname = url.parse(request.url).pathname;
console.log("Request for " + pathname + " received.");
route(handle, pathname, response);
}
http.createServer(onRequest).listen(8888);
console.log("Server has started.");
}
exports.start = start;
and their route function:
function route(handle, pathname, response) {
console.log("About to route a request for " + pathname);
if (typeof handle[pathname] === 'function') {
handle[pathname](response);
} else {
console.log("No request handler found for " + pathname);
response.writeHead(404, {"Content-Type": "text/plain"});
response.write("404 Not found");
response.end();
}
}
exports.route = route;
This is one way. http://www.nodebeginner.org/
From another site, they create a page and then load it. This might be more of what you're looking for.
fs.readFile('www/404.html', function(error2, data) {
response.writeHead(404, {'content-type': 'text/html'});
response.end(data);
});
Solution 5 - Javascript
From the Express site, define a NotFound exception and throw it whenever you want to have a 404 page OR redirect to /404 in the below case:
function NotFound(msg){
this.name = 'NotFound';
Error.call(this, msg);
Error.captureStackTrace(this, arguments.callee);
}
NotFound.prototype.__proto__ = Error.prototype;
app.get('/404', function(req, res){
throw new NotFound;
});
app.get('/500', function(req, res){
throw new Error('keyboard cat!');
});
Solution 6 - Javascript
IMO the nicest way is to use the next()
function:
router.get('/', function(req, res, next) {
var err = new Error('Not found');
err.status = 404;
return next(err);
}
Then the error is handled by your error handler and you can style the error nicely using HTML.