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.
- 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.
Install using npm:
npm install koa-router
- 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 ⏏
Create a new router.
Param | Type | Description |
---|---|---|
[opts] | Object |
|
[opts.prefix] | String |
prefix router paths |
Example
Basic usage:
const Koa = require('koa');
const Router = require('koa-router');
const app = new Koa();
const router = new Router();
router.get('/', function (ctx, next) {
// ctx.router available
});
app
.use(router.routes())
.use(router.allowedMethods());
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('/', function (ctx, next) {
ctx.body = 'Hello World!';
})
.post('/users', function (ctx, next) {
// ...
})
.put('/users/:id', function (ctx, next) {
// ...
})
.del('/users/:id', function (ctx, next) {
// ...
})
.all('/users/:id', function (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.
Routes can optionally have names. This allows generation of URLs and easy renaming of URLs during development.
router.get('user', '/users/:id', function (ctx, next) {
// ...
});
router.url('user', 3);
// => "/users/3"
Multiple middleware may be given:
router.get(
'/users/:id',
function (ctx, next) {
return User.findOne(ctx.params.id).then(function(user) {
ctx.user = user;
return next();
});
},
function (ctx) {
console.log(ctx.user);
// => { id: 17, name: "Alex" }
}
);
Nesting routers is supported:
const forums = new Router();
const posts = new Router();
posts.get('/', function (ctx, next) {...});
posts.get('/:pid', function (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());
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"
Named route parameters are captured and added to ctx.params
.
router.get('/:category/:title', function (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 |
Returns router middleware which dispatches a route matching the request.
Kind: instance property of Router
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());
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')
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
const Koa = require('koa');
const Router = require('koa-router');
const app = new Koa();
const router = new Router();
app.use(router.routes());
app.use(router.allowedMethods());
Example with Boom
const Koa = require('koa');
const Router = require('koa-router');
const Boom = require('boom');
const app = new Koa();
const router = new Router();
app.use(router.routes());
app.use(router.allowedMethods({
throw: true,
notImplemented: () => new Boom.notImplemented(),
methodNotAllowed: () => new Boom.methodNotAllowed()
}));
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', function (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). |
Lookup route with given name
.
Kind: instance method of Router
Param | Type |
---|---|
name | String |
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', function (ctx, next) {
// ...
});
router.url('user', 3);
// => "/users/3"
router.url('user', { id: 3 });
// => "/users/3"
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.use(function (ctx, next) {
// redirect to named route
ctx.redirect(ctx.router.url('sign-in'));
})
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', function (id, ctx, next) {
ctx.user = users[id];
if (!ctx.user) return ctx.status = 404;
return next();
})
.get('/users/:user', function (ctx) {
ctx.body = ctx.user;
})
.get('/users/:user/friends', function (ctx) {
return ctx.user.getFriends().then(function(friends) {
ctx.body = friends;
});
})
// /users/3 => {"id": 3, "name": "Alex"}
// /users/3/friends => [{"id": 4, "name": "TJ"}]
Generate URL from url pattern and given params
.
Kind: static method of Router
Param | Type | Description |
---|---|---|
path | String |
url pattern |
params | Object |
url parameters |
Example
const url = Router.url('/users/:id', {id: 1});
// => "/users/1"
Please submit all issues and pull requests to the alexmingoia/koa-router repository!
Run tests using npm test
.
If you have any problem or suggestion please open an issue here.