When to use app.use and when to use app.all?

Question

In the express documentation, there is the following example:

app.use('/user/:id', function (req, res, next) {
  console.log('Request Type:', req.method)
  next()
})

and it explains that the function is executed for any type of HTTP request on the /user/:idpath. This confuses me as it looks like app.use does the same work as app.all(). Are they the same?

In describing app.use, the documentation always uses the terms mount and path. Whereas for app.get, the term used is always route. What do all these mean?

possible duplicate http://stackoverflow.com/questions/15601703/difference-between-app-use-and-app-get-in-express-js — Asif Saeed, Jan 28 '17 at 08:54
Possible duplicate of [Difference between app.use and app.get in express.js](http://stackoverflow.com/questions/15601703/difference-between-app-use-and-app-get-in-express-js) — cartant, Jan 28 '17 at 09:00

score 0 · Answer 1 · answered Jan 28 '17 at 08:58

0

app.use is typically used for middleware (like cors or a logger). Use app.get when you need to make a get request on your resource.

answered Jan 28 '17 at 08:58

Edward Smith

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score 0 · Answer 2 · 2017-01-28T09:25:19.403

0

The documentation says app.use(....) is executed for ANY type of HTTP request on the /user/:id path whereas the app.get(...) (as an example of app.METHOD ) handles (specifically) GET request made to the given path, same applies to app.post() which ONLY handles HTTP post request.

edited Jan 28 '17 at 09:25

answered Jan 28 '17 at 09:04

score 0 · Answer 3 · answered Jan 28 '17 at 09:23

I understand the router is just another function. Typically router expects mount path not being visible; otherwise in your router you need to repeat the mount path.

router with app.use("/users", router)
router.get('/', function(req, res) {});
router.get('/test', function(req, res) {});

router with app.get("/users", router)
router.get('/users/', function(req, res) {});
router.get('/users/test', function(req, res) {});

in order to use the router with .get the mounting path is repeated making it much less useful.

   app.use( "/product" , mymiddleware);
// will match /product
// will match /product/cool
// will match /product/foo

Notice the difference between use and get? These mean different things in Express.js:

use means “Run this on ALL requests”
get means “Run this on a GET request, for the given URL”

Thanks. My question was on your word `Run`. What is `Run`? Both app.use and app.METHOD perform the same `Run`? — Old Geezer, Jan 28 '17 at 09:58
in other word u can say handle request in use all request handle /product, /product/name — Adiii, Jan 28 '17 at 10:08
I have just found that there is `app.all()`. Is `app.use` then same as `app.all()`? — Old Geezer, Jan 28 '17 at 10:10

When to use app.use and when to use app.all?

3 Answers3