Documentation ¶
Overview ¶
Package httprouter is a trie based high performance HTTP request router.
A trivial example is:
package main import ( "fmt" "github.com/julienschmidt/httprouter" "net/http" "log" ) func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) { fmt.Fprint(w, "Welcome!\n") } func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) { fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name")) } func main() { router := httprouter.New() router.GET("/", Index) router.GET("/hello/:name", Hello) log.Fatal(http.ListenAndServe(":8080", router)) }
The router matches incoming requests by the request method and the path. If a handle is registered for this path and method, the router delegates the request to that function. For the methods GET, POST, PUT, PATCH and DELETE shortcut functions exist to register handles, for all other methods router.Handle can be used.
The registered path, against which the router matches incoming requests, can contain two types of parameters:
Syntax Type :name named parameter *name catch-all parameter
Named parameters are dynamic path segments. They match anything until the next '/' or the path end:
Path: /blog/:category/:post Requests: /blog/go/request-routers match: category="go", post="request-routers" /blog/go/request-routers/ no match, but the router would redirect /blog/go/ no match /blog/go/request-routers/comments no match
Catch-all parameters match anything until the path end, including the directory index (the '/' before the catch-all). Since they match anything until the end, catch-all parameters must always be the final path element.
Path: /files/*filepath Requests: /files/ match: filepath="/" /files/LICENSE match: filepath="/LICENSE" /files/templates/article.html match: filepath="/templates/article.html" /files no match, but the router would redirect
The value of parameters is saved as a slice of the Param struct, consisting each of a key and a value. The slice is passed to the Handle func as a third parameter. There are two ways to retrieve the value of a parameter:
// by the name of the parameter user := ps.ByName("user") // defined by :user or *user // by the index of the parameter. This way you can also get the name (key) thirdKey := ps[2].Key // the name of the 3rd parameter thirdValue := ps[2].Value // the value of the 3rd parameter
Index ¶
- func CleanPath(p string) string
- type Handle
- type Param
- type Params
- type Router
- func (r *Router) DELETE(path string, handle Handle)
- func (r *Router) GET(path string, handle Handle)
- func (r *Router) HEAD(path string, handle Handle)
- func (r *Router) Handle(method, path string, handle Handle)
- func (r *Router) Handler(method, path string, handler http.Handler)
- func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc)
- func (r *Router) Lookup(method, path string) (Handle, Params, bool)
- func (r *Router) OPTIONS(path string, handle Handle)
- func (r *Router) PATCH(path string, handle Handle)
- func (r *Router) POST(path string, handle Handle)
- func (r *Router) PUT(path string, handle Handle)
- func (r *Router) ServeFiles(path string, root http.FileSystem)
- func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request)
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func CleanPath ¶
CleanPath is the URL version of path.Clean, it returns a canonical URL path for p, eliminating . and .. elements.
The following rules are applied iteratively until no further processing can be done:
- Replace multiple slashes with a single slash.
- Eliminate each . path name element (the current directory).
- Eliminate each inner .. path name element (the parent directory) along with the non-.. element that precedes it.
- Eliminate .. elements that begin a rooted path: that is, replace "/.." by "/" at the beginning of a path.
If the result of this process is an empty string, "/" is returned
Types ¶
type Handle ¶
type Handle func(http.ResponseWriter, *http.Request, Params)
Handle is a function that can be registered to a route to handle HTTP requests. Like http.HandlerFunc, but has a third parameter for the values of wildcards (variables).
type Params ¶
type Params []Param
Params is a Param-slice, as returned by the router. The slice is ordered, the first URL parameter is also the first slice value. It is therefore safe to read values by the index.
type Router ¶
type Router struct { // Enables automatic redirection if the current route can't be matched but a // handler for the path with (without) the trailing slash exists. // For example if /foo/ is requested but a route only exists for /foo, the // client is redirected to /foo with http status code 301 for GET requests // and 307 for all other request methods. RedirectTrailingSlash bool // If enabled, the router tries to fix the current request path, if no // handle is registered for it. // First superfluous path elements like ../ or // are removed. // Afterwards the router does a case-insensitive lookup of the cleaned path. // If a handle can be found for this route, the router makes a redirection // to the corrected path with status code 301 for GET requests and 307 for // all other request methods. // For example /FOO and /..//Foo could be redirected to /foo. // RedirectTrailingSlash is independent of this option. RedirectFixedPath bool // If enabled, the router checks if another method is allowed for the // current route, if the current request can not be routed. // If this is the case, the request is answered with 'Method Not Allowed' // and HTTP status code 405. // If no other Method is allowed, the request is delegated to the NotFound // handler. HandleMethodNotAllowed bool // Configurable http.Handler which is called when no matching route is // found. If it is not set, http.NotFound is used. NotFound http.Handler // Configurable http.Handler which is called when a request // cannot be routed and HandleMethodNotAllowed is true. // If it is not set, http.Error with http.StatusMethodNotAllowed is used. MethodNotAllowed http.Handler // Function to handle panics recovered from http handlers. // It should be used to generate a error page and return the http error code // 500 (Internal Server Error). // The handler can be used to keep your server from crashing because of // unrecovered panics. PanicHandler func(http.ResponseWriter, *http.Request, interface{}) // contains filtered or unexported fields }
Router is a http.Handler which can be used to dispatch requests to different handler functions via configurable routes
func New ¶
func New() *Router
New returns a new initialized Router. Path auto-correction, including trailing slashes, is enabled by default.
func (*Router) Handle ¶
Handle registers a new request handle with the given path and method.
For GET, POST, PUT, PATCH and DELETE requests the respective shortcut functions can be used.
This function is intended for bulk loading and to allow the usage of less frequently used, non-standardized or custom methods (e.g. for internal communication with a proxy).
func (*Router) Handler ¶
Handler is an adapter which allows the usage of an http.Handler as a request handle.
func (*Router) HandlerFunc ¶
func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc)
HandlerFunc is an adapter which allows the usage of an http.HandlerFunc as a request handle.
func (*Router) Lookup ¶
Lookup allows the manual lookup of a method + path combo. This is e.g. useful to build a framework around this router. If the path was found, it returns the handle function and the path parameter values. Otherwise the third return value indicates whether a redirection to the same path with an extra / without the trailing slash should be performed.
func (*Router) ServeFiles ¶
func (r *Router) ServeFiles(path string, root http.FileSystem)
ServeFiles serves files from the given file system root. The path must end with "/*filepath", files are then served from the local path /defined/root/dir/*filepath. For example if root is "/etc" and *filepath is "passwd", the local file "/etc/passwd" would be served. Internally a http.FileServer is used, therefore http.NotFound is used instead of the Router's NotFound handler. To use the operating system's file system implementation, use http.Dir:
router.ServeFiles("/src/*filepath", http.Dir("/var/www"))