watson / wayfarer

:eyeglasses: composable trie based router

wayfarer

Composable trie based router. It's faster than traditional, linear, regular expression-matching routers, although insignficantly, and scales with the number of routes.

If you're looking for a client-side router check out sheet-router. If you're looking for a server router check out server-router.

features

• works with any framework
• built for speed
• minimal dependencies
• extensible

Installation

$ npm install wayfarer

Usage

const wayfarer = require('wayfarer')

const router = wayfarer('/404')

router.on('/', () => console.log('/'))
router.on('/404', () => console.log('404 not found'))
router.on('/:user', (params) => console.log('user is %s', params.user))

router('tobi')
// => 'user is tobi'

router('/uh/oh')
// => '404 not found'

Subrouting

Routers can be infinitely nested, allowing routing to be scoped per view. Matched params are passed into subrouters. Nested routes will call their parent's default handler if no path matches.

const r1 = wayfarer()
const r2 = wayfarer()

r2.on('/child', () => console.log('subrouter trix!'))
r1.on('/:parent', r2)

r1('/dada/child')
// => 'subrouter trix!'

Walk

Sometimes it's necessary to walk the trie to apply transformations.

const walk = require('wayfarer/walk')
const wayfarer = require('wayfarer')

const router = wayfarer()
router.on('/multiply', (x, y) => x * y)
router.on('/divide', (x, y) => x / y)

walk(router, (route, cb) => {
  const y = 2
  return function (params, x) {
    return cb(x, y)
  }
})

router('/multiply', 4)
// => 8
router('/divide', 8)
// => 4

API

router = wayfarer(default)

Initialize a router with a default route. Doesn't ignore querystrings and hashes.

router.on(route, cb(params, [arg1, ...]))

Register a new route. The order in which routes are registered does not matter. Routes can register multiple callbacks. The callback can return values when called.

val = router(route, [arg1, ...])

Match a route and execute the corresponding callback. Alias: router.emit(). Returns a values from the matched route (e.g. useful for streams). Any additional values will be passed to the matched route.

Internals

Wayfarer is built on an internal trie structure. If you want to build a router using this trie structure it can be accessed through require('wayfarer/trie'). It exposes the following methods:

• trie = Trie() - create a new trie
• node = trie.create(route) - create a node at a path, and return a node
• node = trie.match(route) - match a route on the the trie and return a node
• trie.mount(path, trie) - mount a trie onto a node at route

Known issues

multiple nested partials don't match

E.g. /:foo/:bar/:baz won't work. This is due Trie.mount() overriding child partial paths when mounted. I'll get around to fixing this at some point in the future, but if anyone wants to contribute a patch it'd most appreciated.

FAQ

Why did you build this?

Routers like react-router are complicated solutions for a simple problem. In reality all that's needed is a methodless router that can define + match paths and can mount other routers to delegate requests.

Why isn't my route matching?

Wayfarer only compares strings. Before you pass in an url you probably want to strip it of querystrings and hashes using the pathname-match module.

See Also

• sheet-router - fast, modular client-side router
• server-router - server router
• hash-match - easy window.location.hash matching
• pathname-match - strip querystrings and hashes from a url
• wayfarer-to-server - Wrap wayfarer to provide HTTP method matching and req, res delegation

License

MIT