README
koa-router
Router middleware for koa
- Express-style routing using
app.get
,app.put
,app.post
, etc. - Named URL parameters.
- Named routes with URL generation.
- Responds to
OPTIONS
requests with allowed methods. - Support for
405 Method Not Allowed
and501 Not Implemented
. - Multiple route middleware.
- Multiple routers.
- Nestable routers.
- ES7 async/await support.
Migrating to 7 / Koa 2
- The API has changed to match the new promise-based middleware signature of koa 2. See the koa 2.x readme for more information.
- Middleware is now always run in the order declared by
.use()
(or.get()
, etc.), which matches Express 4 API.
Installation
Install using npm:
npm install koa-router
API Reference
- koa-router
- Router ⏏
- new Router([opts])
- instance
- .get|put|post|patch|delete|del ⇒
Router
- .routes ⇒
function
- .use([path], middleware) ⇒
Router
- .prefix(prefix) ⇒
Router
- .allowedMethods([options]) ⇒
function
- .redirect(source, destination, [code]) ⇒
Router
- .route(name) ⇒
Layer
|false
- .url(name, params, [options]) ⇒
String
|Error
- .param(param, middleware) ⇒
Router
- .get|put|post|patch|delete|del ⇒
- static
- .url(path, params) ⇒
String
- .url(path, params) ⇒
- Router ⏏
Router ⏏
new Router([opts])
Create a new router.
Param | Type | Description |
---|---|---|
[opts] | Object |
|
[opts.prefix] | String |
prefix router paths |
Example
Basic usage:
var Koa = require('koa');
var Router = require('koa-router');
var app = new Koa();
var router = new Router();
router.get('/', (ctx, next) => {
// ctx.router available
});
app
.use(router.routes())
.use(router.allowedMethods());
Router
router.get|put|post|patch|delete|del ⇒ Create router.verb()
methods, where verb is one of the HTTP verbs such
as router.get()
or router.post()
.
Match URL patterns to callback functions or controller actions using router.verb()
,
where verb is one of the HTTP verbs such as router.get()
or router.post()
.
Additionaly, router.all()
can be used to match against all methods.
router
.get('/', (ctx, next) => {
ctx.body = 'Hello World!';
})
.post('/users', (ctx, next) => {
// ...
})
.put('/users/:id', (ctx, next) => {
// ...
})
.del('/users/:id', (ctx, next) => {
// ...
})
.all('/users/:id', (ctx, next) => {
// ...
});
When a route is matched, its path is available at ctx._matchedRoute
and if named,
the name is available at ctx._matchedRouteName
Route paths will be translated to regular expressions using path-to-regexp.
Query strings will not be considered when matching requests.
Named routes
Routes can optionally have names. This allows generation of URLs and easy renaming of URLs during development.
router.get('user', '/users/:id', (ctx, next) => {
// ...
});
router.url('user', 3);
// => "/users/3"
Multiple middleware
Multiple middleware may be given:
router.get(
'/users/:id',
(ctx, next) => {
return User.findOne(ctx.params.id).then(function(user) {
ctx.user = user;
next();
});
},
ctx => {
console.log(ctx.user);
// => { id: 17, name: "Alex" }
}
);
Nested routers
Nesting routers is supported:
var forums = new Router();
var posts = new Router();
posts.get('/', (ctx, next) => {...});
posts.get('/:pid', (ctx, next) => {...});
forums.use('/forums/:fid/posts', posts.routes(), posts.allowedMethods());
// responds to "/forums/123/posts" and "/forums/123/posts/123"
app.use(forums.routes());
Router prefixes
Route paths can be prefixed at the router level:
var router = new Router({
prefix: '/users'
});
router.get('/', ...); // responds to "/users"
router.get('/:id', ...); // responds to "/users/:id"
URL parameters
Named route parameters are captured and added to ctx.params
.
router.get('/:category/:title', (ctx, next) => {
console.log(ctx.params);
// => { category: 'programming', title: 'how-to-node' }
});
The path-to-regexp module is used to convert paths to regular expressions.
Kind: instance property of Router
Param | Type | Description |
---|---|---|
path | String |
|
[middleware] | function |
route middleware(s) |
callback | function |
route callback |
function
router.routes ⇒ Returns router middleware which dispatches a route matching the request.
Kind: instance property of Router
Router
router.use([path], middleware) ⇒ Use given middleware.
Middleware run in the order they are defined by .use()
. They are invoked
sequentially, requests start at the first middleware and work their way
"down" the middleware stack.
Kind: instance method of Router
Param | Type |
---|---|
[path] | String |
middleware | function |
[...] | function |
Example
// session middleware will run before authorize
router
.use(session())
.use(authorize());
// use middleware only with given path
router.use('/users', userAuth());
// or with an array of paths
router.use(['/users', '/admin'], userAuth());
app.use(router.routes());
Router
router.prefix(prefix) ⇒ Set the path prefix for a Router instance that was already initialized.
Kind: instance method of Router
Param | Type |
---|---|
prefix | String |
Example
router.prefix('/things/:thing_id')
function
router.allowedMethods([options]) ⇒ Returns separate middleware for responding to OPTIONS
requests with
an Allow
header containing the allowed methods, as well as responding
with 405 Method Not Allowed
and 501 Not Implemented
as appropriate.
Kind: instance method of Router
Param | Type | Description |
---|---|---|
[options] | Object |
|
[options.throw] | Boolean |
throw error instead of setting status and header |
[options.notImplemented] | function |
throw the returned value in place of the default NotImplemented error |
[options.methodNotAllowed] | function |
throw the returned value in place of the default MethodNotAllowed error |
Example
var Koa = require('koa');
var Router = require('koa-router');
var app = new Koa();
var router = new Router();
app.use(router.routes());
app.use(router.allowedMethods());
Example with Boom
var Koa = require('koa');
var Router = require('koa-router');
var Boom = require('boom');
var app = new Koa();
var router = new Router();
app.use(router.routes());
app.use(router.allowedMethods({
throw: true,
notImplemented: () => new Boom.notImplemented(),
methodNotAllowed: () => new Boom.methodNotAllowed()
}));
Router
router.redirect(source, destination, [code]) ⇒ Redirect source
to destination
URL with optional 30x status code
.
Both source
and destination
can be route names.
router.redirect('/login', 'sign-in');
This is equivalent to:
router.all('/login', ctx => {
ctx.redirect('/sign-in');
ctx.status = 301;
});
Kind: instance method of Router
Param | Type | Description |
---|---|---|
source | String |
URL or route name. |
destination | String |
URL or route name. |
[code] | Number |
HTTP status code (default: 301). |
Layer
| false
router.route(name) ⇒ Lookup route with given name
.
Kind: instance method of Router
Param | Type |
---|---|
name | String |
String
| Error
router.url(name, params, [options]) ⇒ Generate URL for route. Takes a route name and map of named params
.
Kind: instance method of Router
Param | Type | Description |
---|---|---|
name | String |
route name |
params | Object |
url parameters |
[options] | Object |
options parameter |
[options.query] | Object | String |
query options |
Example
router.get('user', '/users/:id', (ctx, next) => {
// ...
});
router.url('user', 3);
// => "/users/3"
router.url('user', { id: 3 });
// => "/users/3"
router.use((ctx, next) => {
// redirect to named route
ctx.redirect(ctx.router.url('sign-in'));
})
router.url('user', { id: 3 }, { query: { limit: 1 } });
// => "/users/3?limit=1"
router.url('user', { id: 3 }, { query: "limit=1" });
// => "/users/3?limit=1"
Router
router.param(param, middleware) ⇒ Run middleware for named route parameters. Useful for auto-loading or validation.
Kind: instance method of Router
Param | Type |
---|---|
param | String |
middleware | function |
Example
router
.param('user', (id, ctx, next) => {
ctx.user = users[id];
if (!ctx.user) return ctx.status = 404;
return next();
})
.get('/users/:user', ctx => {
ctx.body = ctx.user;
})
.get('/users/:user/friends', ctx => {
return ctx.user.getFriends().then(function(friends) {
ctx.body = friends;
});
})
// /users/3 => {"id": 3, "name": "Alex"}
// /users/3/friends => [{"id": 4, "name": "TJ"}]
String
Router.url(path, params [, options]) ⇒ Generate URL from url pattern and given params
.
Kind: static method of Router
Param | Type | Description |
---|---|---|
path | String |
url pattern |
params | Object |
url parameters |
[options] | Object |
options parameter |
[options.query] | Object | String |
query options |
Example
var url = Router.url('/users/:id', {id: 1});
// => "/users/1"
const url = Router.url('/users/:id', {id: 1}, {query: { active: true }});
// => "/users/1?active=true"
Contributing
Please submit all issues and pull requests to the alexmingoia/koa-router repository!
Tests
Run tests using npm test
.
Support
If you have any problem or suggestion please open an issue here.