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javascriptnode.jsexpressexpress-router

Why is express matching two routes?

I have an express API with a bunch of routes.

routes.get('/',                      perms('read', 'document'),   r(CRUD.getAll))
routes.get('/search',                perms('read', 'document'),   r(CRUD.search))
routes.get('/:id',                   perms('read', 'document'),   r(CRUD.getById))

I made sure to have /search above /:id, however, when a new request comes in to /search, I see both endpoints getting a hit (I added a console.log inside of each function).

I tried flipping the two and in that case, only /:id gets a hit.

Any idea of why this may be happening?

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Solution

  • Think about Express routing as an array of handlers (middlewares), that have a matching rule (url). When a request comes in, the router starts checking each item in the array from the beginning. If it matches the rule, then the handler is run (some don't have conditions, so they just run on each request :)). The request chain does not end when a single url is matched! You can execute multiple handlers on the same request (and that's exactly how middlewares work).

    Therefore, it really depends on what happens inside your handler. You can tell it to continue with the next item in the list, and if there's a match - the next handler will be executed (like /search and /:id, which will be search again).

    Make sure you end your response. Beware if you call next and with what parameters. Post some samples of the handlers in order to debug it more :)