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Route Patterns

Below we’ll list some of the common route-matching patterns supported by itty-router. By default, all matched route params are accessible in the handlers as request.params, unless using the withParams middleware.

1. Fixed routes

Any fixed string will require a direct match.

router.get('/foo/bar/baz', handler)

// GET /foo/bar/baz

2. Simple route params

Prefix any named route param with a : to capture it. These are separated by slashes.

router.get('/todos/:id/:action', handler)

// GET /todos/13/edit

3. Optional route params

Make a route parameter optional by adding a ? after the name. In this example, actions becomes an optional parameter, allowing requests to match with or without it.

router.get('/todos/:id/:action?', handler)

// GET /todos/13
// GET /todos/13/edit

4. File formats/extensions

To capture a filename + extension, simply include the period before a final named group.

router.get('/files/:file.:extension', handler)
// GET /files/kitten.jpeg ==> { file: 'kitten', extension: 'jpg' }

router.get('/files/manifest.:extension?', handler)
// GET /files/manifest ==> {}
// GET /files/manifest.json ==> { extension: 'json' }

5. Wildcards

Especially useful for global middleware, nesting routers, etc., the wildcard * allows a route to match anything preceeding the *. It should be noted that this is a non-capturing group, and merely to allow matching.

router.all('*', handler)
// GET /todos/13/edit
// PUT /foo/bar
// GET /

router.get('/test/*', handler)
// GET /test/todos/13/edit
// GET /test/foo/bar

6. “Greedy” params

A final named route param may be set as “greedy” by adding a + to the end. This will capture anything following, including slashes and otherwise challenging characters.

For example:

router.get('/goto/:url+', handler)
// GET /goto/

Returns the following params:

  "url": ""

6. Query params

As a convenience, we embed a parsed query object into the Request. This will always be an object, with keys matching any query names found in the path. If more than one value is found for the same key (e.g. /?foo=bar&foo=baz), the value will be an array of the listed values.

NOTE: The query string will not be considered during route matching, and therefore should not be included in a route definition.

For example:

router.get('/', (request) => request.query)
// GET /?name=Kevin&pets=Vlad&pets=Katiya&pets=Halsey

Gives us the following response:

  "name": "Kevin",
  "pets": ["Vlad", "Katiya", "Halsey"],