What Does `app.use(express.static())` Do in Express?
What Does `app.use(express.static())` Do in Express?
In Express, app.use(express.static()) adds a middleware for serving static files
to your Express app.
For example, suppose you have the below public directory in your project:
$ ls -l public/
total 48
-rw-r--r-- 1
ubuntu ubuntu 1666
Mar 12
14
:17
home.css
-rw-r--r--@ 1
ubuntu ubuntu 17092
Mar 12
14
:17
logo.png
$ You can use the express.static middleware to make it possible to access files from this folder via HTTP.
const
express = require
('express'
);
const
app = express();
app.use(express.static('./public'
));
app.listen(3000
);With the above script, you can open http://localhost:3000/home.css in your browser and see the CSS file.
Order Matters!
Keep in mind the app.use() function executes middleware in order.
The express.static() middleware returns an HTTP 404 if it can’t find a file, so
that means you should typically call app.use(express.static()) after the rest of your app. Otherwise you’ll end
up with an HTTP 404 error:
const
express = require
('express'
);
const
app = express();
app.use(express.static('./public'
));
app.get('/test'
, function
requestHandler
(req, res
) {
res.send('ok'
);
});
app.listen(3000
);Make sure you put express.static() last:
const
express = require
('express'
);
const
app = express();
app.get('/test'
, function
requestHandler
(req, res
) {
res.send('ok'
);
});
app.use(express.static('./public'
));
app.listen(3000
);
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