README

httptreemux Build Status GoDoc

High-speed, flexible, tree-based HTTP router for Go.

This is inspired by Julien Schmidt's httprouter, in that it uses a patricia tree, but the implementation is rather different. Specifically, the routing rules are relaxed so that a single path segment may be a wildcard in one route and a static token in another. This gives a nice combination of high performance with a lot of convenience in designing the routing patterns. In benchmarks, httptreemux is close to, but slightly slower than, httprouter.

Release notes may be found using the Github releases tab. Version numbers are compatible with the Semantic Versioning 2.0.0 convention, and a new release is made after every change to the code.

Why?

There are a lot of good routers out there. But looking at the ones that were really lightweight, I couldn't quite get something that fit with the route patterns I wanted. The code itself is simple enough, so I spent an evening writing this.

Handler

The handler is a simple function with the prototype func(w http.ResponseWriter, r *http.Request, params map[string]string). The params argument contains the parameters parsed from wildcards and catch-alls in the URL, as described below. This type is aliased as httptreemux.HandlerFunc.

Using http.HandlerFunc

Due to the inclusion of the context package as of Go 1.7, httptreemux now supports handlers of type http.HandlerFunc. There are two ways to enable this support.

Adapting an Existing Router

The UsingContext method will wrap the router or group in a new group at the same path, but adapted for use with context and http.HandlerFunc.

router := httptreemux.New()

group := router.NewGroup("/api")
group.GET("/v1/:id", func(w http.ResponseWriter, r *http.Request, params map[string]string) {
    id := params["id"]
    fmt.Fprintf(w, "GET /api/v1/%s", id)
})

// UsingContext returns a version of the router or group with context support.
ctxGroup := group.UsingContext() // sibling to 'group' node in tree
ctxGroup.GET("/v2/:id", func(w http.ResponseWriter, r *http.Request) {
    params := httptreemux.ContextParams(r.Context())
    id := params["id"]
    fmt.Fprintf(w, "GET /api/v2/%s", id)
})

http.ListenAndServe(":8080", router)
New Router with Context Support

The NewContextMux function returns a router preconfigured for use with context and http.HandlerFunc.

router := httptreemux.NewContextMux()

router.GET("/:page", func(w http.ResponseWriter, r *http.Request) {
    params := httptreemux.ContextParams(r.Context())
    fmt.Fprintf(w, "GET /%s", params["page"])
})

group := tree.NewGroup("/api")
group.GET("/v1/:id", func(w http.ResponseWriter, r *http.Request) {
    params := httptreemux.ContextParams(r.Context())
    id := params["id"]
    fmt.Fprintf(w, "GET /api/v1/%s", id)
})

http.ListenAndServe(":8080", router)

Routing Rules

The syntax here is also modeled after httprouter. Each variable in a path may match on one segment only, except for an optional catch-all variable at the end of the URL.

Some examples of valid URL patterns are:

  • /post/all
  • /post/:postid
  • /post/:postid/page/:page
  • /post/:postid/:page
  • /images/*path
  • /favicon.ico
  • /:year/:month/
  • /:year/:month/:post
  • /:page

Note that all of the above URL patterns may exist concurrently in the router.

Path elements starting with : indicate a wildcard in the path. A wildcard will only match on a single path segment. That is, the pattern /post/:postid will match on /post/1 or /post/1/, but not /post/1/2.

A path element starting with * is a catch-all, whose value will be a string containing all text in the URL matched by the wildcards. For example, with a pattern of /images/*path and a requested URL images/abc/def, path would contain abc/def.

Using : and * in routing patterns

The characters : and * can be used at the beginning of a path segment by escaping them with a backslash. A double backslash at the beginning of a segment is interpreted as a single backslash. These escapes are only checked at the very beginning of a path segment; they are not necessary or processed elsewhere in a token.

router.GET("/foo/\\*starToken", handler) // matches /foo/*starToken
router.GET("/foo/star*inTheMiddle", handler) // matches /foo/star*inTheMiddle
router.GET("/foo/starBackslash\\*", handler) // matches /foo/starBackslash\*
router.GET("/foo/\\\\*backslashWithStar") // matches /foo/\*backslashWithStar
Routing Groups

Lets you create a new group of routes with a given path prefix. Makes it easier to create clusters of paths like:

  • /api/v1/foo
  • /api/v1/bar

To use this you do:

router = httptreemux.New()
api := router.NewGroup("/api/v1")
api.GET("/foo", fooHandler) // becomes /api/v1/foo
api.GET("/bar", barHandler) // becomes /api/v1/bar
Routing Priority

The priority rules in the router are simple.

  1. Static path segments take the highest priority. If a segment and its subtree are able to match the URL, that match is returned.
  2. Wildcards take second priority. For a particular wildcard to match, that wildcard and its subtree must match the URL.
  3. Finally, a catch-all rule will match when the earlier path segments have matched, and none of the static or wildcard conditions have matched. Catch-all rules must be at the end of a pattern.

So with the following patterns adapted from simpleblog, we'll see certain matches:

router = httptreemux.New()
router.GET("/:page", pageHandler)
router.GET("/:year/:month/:post", postHandler)
router.GET("/:year/:month", archiveHandler)
router.GET("/images/*path", staticHandler)
router.GET("/favicon.ico", staticHandler)
Example scenarios
  • /abc will match /:page
  • /2014/05 will match /:year/:month
  • /2014/05/really-great-blog-post will match /:year/:month/:post
  • /images/CoolImage.gif will match /images/*path
  • /images/2014/05/MayImage.jpg will also match /images/*path, with all the text after /images stored in the variable path.
  • /favicon.ico will match /favicon.ico
Special Method Behavior

If TreeMux.HeadCanUseGet is set to true, the router will call the GET handler for a pattern when a HEAD request is processed, if no HEAD handler has been added for that pattern. This behavior is enabled by default.

Go's http.ServeContent and related functions already handle the HEAD method correctly by sending only the header, so in most cases your handlers will not need any special cases for it.

By default TreeMux.OptionsHandler is a null handler that doesn't affect your routing. If you set the handler, it will be called on OPTIONS requests to a path already registered by another method. If you set a path specific handler by using router.OPTIONS, it will override the global Options Handler for that path.

Trailing Slashes

The router has special handling for paths with trailing slashes. If a pattern is added to the router with a trailing slash, any matches on that pattern without a trailing slash will be redirected to the version with the slash. If a pattern does not have a trailing slash, matches on that pattern with a trailing slash will be redirected to the version without.

The trailing slash flag is only stored once for a pattern. That is, if a pattern is added for a method with a trailing slash, all other methods for that pattern will also be considered to have a trailing slash, regardless of whether or not it is specified for those methods too. However this behavior can be turned off by setting TreeMux.RedirectTrailingSlash to false. By default it is set to true.

One exception to this rule is catch-all patterns. By default, trailing slash redirection is disabled on catch-all patterns, since the structure of the entire URL and the desired patterns can not be predicted. If trailing slash removal is desired on catch-all patterns, set TreeMux.RemoveCatchAllTrailingSlash to true.

router = httptreemux.New()
router.GET("/about", pageHandler)
router.GET("/posts/", postIndexHandler)
router.POST("/posts", postFormHandler)

GET /about will match normally.
GET /about/ will redirect to /about.
GET /posts will redirect to /posts/.
GET /posts/ will match normally.
POST /posts will redirect to /posts/, because the GET method used a trailing slash.
Custom Redirects

RedirectBehavior sets the behavior when the router redirects the request to the canonical version of the requested URL using RedirectTrailingSlash or RedirectClean. The default behavior is to return a 301 status, redirecting the browser to the version of the URL that matches the given pattern.

These are the values accepted for RedirectBehavior. You may also add these values to the RedirectMethodBehavior map to define custom per-method redirect behavior.

  • Redirect301 - HTTP 301 Moved Permanently; this is the default.
  • Redirect307 - HTTP/1.1 Temporary Redirect
  • Redirect308 - RFC7538 Permanent Redirect
  • UseHandler - Don't redirect to the canonical path. Just call the handler instead.
Rationale/Usage

On a POST request, most browsers that receive a 301 will submit a GET request to the redirected URL, meaning that any data will likely be lost. If you want to handle and avoid this behavior, you may use Redirect307, which causes most browsers to resubmit the request using the original method and request body.

Since 307 is supposed to be a temporary redirect, the new 308 status code has been proposed, which is treated the same, except it indicates correctly that the redirection is permanent. The big caveat here is that the RFC is relatively recent, and older or non-compliant browsers will not handle it. Therefore its use is not recommended unless you really know what you're doing.

Finally, the UseHandler value will simply call the handler function for the pattern, without redirecting to the canonical version of the URL.

RequestURI vs. URL.Path
Escaped Slashes

Go automatically processes escaped characters in a URL, converting + to a space and %XX to the corresponding character. This can present issues when the URL contains a %2f, which is unescaped to '/'. This isn't an issue for most applications, but it will prevent the router from correctly matching paths and wildcards.

For example, the pattern /post/:post would not match on /post/abc%2fdef, which is unescaped to /post/abc/def. The desired behavior is that it matches, and the post wildcard is set to abc/def.

Therefore, this router defaults to using the raw URL, stored in the Request.RequestURI variable. Matching wildcards and catch-alls are then unescaped, to give the desired behavior.

TL;DR: If a requested URL contains a %2f, this router will still do the right thing. Some Go HTTP routers may not due to Go issue 3659.

Escaped Characters

As mentioned above, characters in the URL are not unescaped when using RequestURI to determine the matched route. If this is a problem for you and you are unable to switch to URL.Path for the above reasons, you may set router.EscapeAddedRoutes to true. This option will run each added route through the URL.EscapedPath function, and add an additional route if the escaped version differs.

http Package Utility Functions

Although using RequestURI avoids the issue described above, certain utility functions such as http.StripPrefix modify URL.Path, and expect that the underlying router is using that field to make its decision. If you are using some of these functions, set the router's PathSource member to URLPath. This will give up the proper handling of escaped slashes described above, while allowing the router to work properly with these utility functions.

Concurrency

The router contains an RWMutex that arbitrates access to the tree. This allows routes to be safely added from multiple goroutines at once.

No concurrency controls are needed when only reading from the tree, so the default behavior is to not use the RWMutex when serving a request. This avoids a theoretical slowdown under high-usage scenarios from competing atomic integer operations inside the RWMutex. If your application adds routes to the router after it has begun serving requests, you should avoid potential race conditions by setting router.SafeAddRoutesWhileRunning to true to use the RWMutex when serving requests.

Error Handlers

NotFoundHandler

TreeMux.NotFoundHandler can be set to provide custom 404-error handling. The default implementation is Go's http.NotFound function.

MethodNotAllowedHandler

If a pattern matches, but the pattern does not have an associated handler for the requested method, the router calls the MethodNotAllowedHandler. The default version of this handler just writes the status code http.StatusMethodNotAllowed and sets the response header's Allowed field appropriately.

Panic Handling

TreeMux.PanicHandler can be set to provide custom panic handling. The SimplePanicHandler just writes the status code http.StatusInternalServerError. The function ShowErrorsPanicHandler, adapted from gocraft/web, will print panic errors to the browser in an easily-readable format.

Unexpected Differences from Other Routers

This router is intentionally light on features in the name of simplicity and performance. When coming from another router that does heavier processing behind the scenes, you may encounter some unexpected behavior. This list is by no means exhaustive, but covers some nonobvious cases that users have encountered.

gorilla/pat query string modifications

When matching on parameters in a route, the gorilla/pat router will modify Request.URL.RawQuery to make it appear like the parameters were in the query string. httptreemux does not do this. See Issue #26 for more details and a code snippet that can perform this transformation for you, should you want it.

Middleware

This package provides no middleware. But there are a lot of great options out there and it's pretty easy to write your own.

Acknowledgements

Documentation

Overview

    This is inspired by Julien Schmidt's httprouter, in that it uses a patricia tree, but the implementation is rather different. Specifically, the routing rules are relaxed so that a single path segment may be a wildcard in one route and a static token in another. This gives a nice combination of high performance with a lot of convenience in designing the routing patterns.

    Index

    Constants

    View Source
    const (
    	Redirect301 RedirectBehavior = iota // Return 301 Moved Permanently
    	Redirect307                         // Return 307 HTTP/1.1 Temporary Redirect
    	Redirect308                         // Return a 308 RFC7538 Permanent Redirect
    	UseHandler                          // Just call the handler function
    
    	RequestURI PathSource = iota // Use r.RequestURI
    	URLPath                      // Use r.URL.Path
    )

    Variables

    This section is empty.

    Functions

    func AddParamsToContext

    func AddParamsToContext(ctx context.Context, params map[string]string) context.Context

      AddParamsToContext inserts a parameters map into a context using the package's internal context key. Clients of this package should really only use this for unit tests.

      func Clean

      func Clean(p string) string

        Clean 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:

        1. Replace multiple slashes with a single slash.
        2. Eliminate each . path name element (the current directory).
        3. Eliminate each inner .. path name element (the parent directory)
           along with the non-.. element that precedes it.
        4. 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

        func ContextParams

        func ContextParams(ctx context.Context) map[string]string

          ContextParams returns the params map associated with the given context if one exists. Otherwise, an empty map is returned.

          func MethodNotAllowedHandler

          func MethodNotAllowedHandler(w http.ResponseWriter, r *http.Request,
          	methods map[string]HandlerFunc)

            MethodNotAllowedHandler is the default handler for TreeMux.MethodNotAllowedHandler, which is called for patterns that match, but do not have a handler installed for the requested method. It simply writes the status code http.StatusMethodNotAllowed and fills in the `Allow` header value appropriately.

            func ShowErrorsJsonPanicHandler

            func ShowErrorsJsonPanicHandler(w http.ResponseWriter, r *http.Request, err interface{})

            func ShowErrorsPanicHandler

            func ShowErrorsPanicHandler(w http.ResponseWriter, r *http.Request, err interface{})

              ShowErrorsPanicHandler prints a nice representation of an error to the browser. This was taken from github.com/gocraft/web, which adapted it from the Traffic project.

              func SimplePanicHandler

              func SimplePanicHandler(w http.ResponseWriter, r *http.Request, err interface{})

                SimplePanicHandler just returns error 500.

                Types

                type ContextGroup

                type ContextGroup struct {
                	// contains filtered or unexported fields
                }

                  ContextGroup is a wrapper around Group, with the purpose of mimicking its API, but with the use of http.HandlerFunc-based handlers. Instead of passing a parameter map via the handler (i.e. httptreemux.HandlerFunc), the path parameters are accessed via the request object's context.

                  func (*ContextGroup) DELETE

                  func (cg *ContextGroup) DELETE(path string, handler http.HandlerFunc)

                    DELETE is convenience method for handling DELETE requests on a context group.

                    func (*ContextGroup) GET

                    func (cg *ContextGroup) GET(path string, handler http.HandlerFunc)

                      GET is convenience method for handling GET requests on a context group.

                      func (*ContextGroup) HEAD

                      func (cg *ContextGroup) HEAD(path string, handler http.HandlerFunc)

                        HEAD is convenience method for handling HEAD requests on a context group.

                        func (*ContextGroup) Handle

                        func (cg *ContextGroup) Handle(method, path string, handler http.HandlerFunc)

                          Handle allows handling HTTP requests via an http.HandlerFunc, as opposed to an httptreemux.HandlerFunc. Any parameters from the request URL are stored in a map[string]string in the request's context.

                          func (*ContextGroup) Handler

                          func (cg *ContextGroup) Handler(method, path string, handler http.Handler)

                            Handler allows handling HTTP requests via an http.Handler interface, as opposed to an httptreemux.HandlerFunc. Any parameters from the request URL are stored in a map[string]string in the request's context.

                            func (*ContextGroup) NewContextGroup

                            func (cg *ContextGroup) NewContextGroup(path string) *ContextGroup

                              NewContextGroup adds a child context group to its path.

                              func (*ContextGroup) NewGroup

                              func (cg *ContextGroup) NewGroup(path string) *ContextGroup

                              func (*ContextGroup) OPTIONS

                              func (cg *ContextGroup) OPTIONS(path string, handler http.HandlerFunc)

                                OPTIONS is convenience method for handling OPTIONS requests on a context group.

                                func (*ContextGroup) PATCH

                                func (cg *ContextGroup) PATCH(path string, handler http.HandlerFunc)

                                  PATCH is convenience method for handling PATCH requests on a context group.

                                  func (*ContextGroup) POST

                                  func (cg *ContextGroup) POST(path string, handler http.HandlerFunc)

                                    POST is convenience method for handling POST requests on a context group.

                                    func (*ContextGroup) PUT

                                    func (cg *ContextGroup) PUT(path string, handler http.HandlerFunc)

                                      PUT is convenience method for handling PUT requests on a context group.

                                      type ContextMux

                                      type ContextMux struct {
                                      	*TreeMux
                                      	*ContextGroup
                                      }

                                      func NewContextMux

                                      func NewContextMux() *ContextMux

                                        NewContextMux returns a TreeMux preconfigured to work with standard http Handler functions and context objects.

                                        func (*ContextMux) DELETE

                                        func (cm *ContextMux) DELETE(path string, handler http.HandlerFunc)

                                          DELETE is convenience method for handling DELETE requests on a context group.

                                          func (*ContextMux) GET

                                          func (cm *ContextMux) GET(path string, handler http.HandlerFunc)

                                            GET is convenience method for handling GET requests on a context group.

                                            func (*ContextMux) HEAD

                                            func (cm *ContextMux) HEAD(path string, handler http.HandlerFunc)

                                              HEAD is convenience method for handling HEAD requests on a context group.

                                              func (*ContextMux) NewGroup

                                              func (cm *ContextMux) NewGroup(path string) *ContextGroup

                                              func (*ContextMux) OPTIONS

                                              func (cm *ContextMux) OPTIONS(path string, handler http.HandlerFunc)

                                                OPTIONS is convenience method for handling OPTIONS requests on a context group.

                                                func (*ContextMux) PATCH

                                                func (cm *ContextMux) PATCH(path string, handler http.HandlerFunc)

                                                  PATCH is convenience method for handling PATCH requests on a context group.

                                                  func (*ContextMux) POST

                                                  func (cm *ContextMux) POST(path string, handler http.HandlerFunc)

                                                    POST is convenience method for handling POST requests on a context group.

                                                    func (*ContextMux) PUT

                                                    func (cm *ContextMux) PUT(path string, handler http.HandlerFunc)

                                                      PUT is convenience method for handling PUT requests on a context group.

                                                      type Group

                                                      type Group struct {
                                                      	// contains filtered or unexported fields
                                                      }

                                                      func (*Group) DELETE

                                                      func (g *Group) DELETE(path string, handler HandlerFunc)

                                                        Syntactic sugar for Handle("DELETE", path, handler)

                                                        func (*Group) GET

                                                        func (g *Group) GET(path string, handler HandlerFunc)

                                                          Syntactic sugar for Handle("GET", path, handler)

                                                          func (*Group) HEAD

                                                          func (g *Group) HEAD(path string, handler HandlerFunc)

                                                            Syntactic sugar for Handle("HEAD", path, handler)

                                                            func (*Group) Handle

                                                            func (g *Group) Handle(method string, path string, handler HandlerFunc)

                                                              Path elements starting with : indicate a wildcard in the path. A wildcard will only match on a single path segment. That is, the pattern `/post/:postid` will match on `/post/1` or `/post/1/`, but not `/post/1/2`.

                                                              A path element starting with * is a catch-all, whose value will be a string containing all text in the URL matched by the wildcards. For example, with a pattern of `/images/*path` and a requested URL `images/abc/def`, path would contain `abc/def`.

                                                              # Routing Rule Priority

                                                              The priority rules in the router are simple.

                                                              1. Static path segments take the highest priority. If a segment and its subtree are able to match the URL, that match is returned.

                                                              2. Wildcards take second priority. For a particular wildcard to match, that wildcard and its subtree must match the URL.

                                                              3. Finally, a catch-all rule will match when the earlier path segments have matched, and none of the static or wildcard conditions have matched. Catch-all rules must be at the end of a pattern.

                                                              So with the following patterns, we'll see certain matches:

                                                              router = httptreemux.New()
                                                              router.GET("/:page", pageHandler)
                                                              router.GET("/:year/:month/:post", postHandler)
                                                              router.GET("/:year/:month", archiveHandler)
                                                              router.GET("/images/*path", staticHandler)
                                                              router.GET("/favicon.ico", staticHandler)
                                                              
                                                              /abc will match /:page
                                                              /2014/05 will match /:year/:month
                                                              /2014/05/really-great-blog-post will match /:year/:month/:post
                                                              /images/CoolImage.gif will match /images/*path
                                                              /images/2014/05/MayImage.jpg will also match /images/*path, with all the text after /images stored in the variable path.
                                                              /favicon.ico will match /favicon.ico
                                                              

                                                              # Trailing Slashes

                                                              The router has special handling for paths with trailing slashes. If a pattern is added to the router with a trailing slash, any matches on that pattern without a trailing slash will be redirected to the version with the slash. If a pattern does not have a trailing slash, matches on that pattern with a trailing slash will be redirected to the version without.

                                                              The trailing slash flag is only stored once for a pattern. That is, if a pattern is added for a method with a trailing slash, all other methods for that pattern will also be considered to have a trailing slash, regardless of whether or not it is specified for those methods too.

                                                              This behavior can be turned off by setting TreeMux.RedirectTrailingSlash to false. By default it is set to true. The specifics of the redirect depend on RedirectBehavior.

                                                              One exception to this rule is catch-all patterns. By default, trailing slash redirection is disabled on catch-all patterns, since the structure of the entire URL and the desired patterns can not be predicted. If trailing slash removal is desired on catch-all patterns, set TreeMux.RemoveCatchAllTrailingSlash to true.

                                                              router = httptreemux.New()
                                                              router.GET("/about", pageHandler)
                                                              router.GET("/posts/", postIndexHandler)
                                                              router.POST("/posts", postFormHandler)
                                                              
                                                              GET /about will match normally.
                                                              GET /about/ will redirect to /about.
                                                              GET /posts will redirect to /posts/.
                                                              GET /posts/ will match normally.
                                                              POST /posts will redirect to /posts/, because the GET method used a trailing slash.
                                                              

                                                              func (*Group) NewGroup

                                                              func (g *Group) NewGroup(path string) *Group

                                                                Add a sub-group to this group

                                                                func (*Group) OPTIONS

                                                                func (g *Group) OPTIONS(path string, handler HandlerFunc)

                                                                  Syntactic sugar for Handle("OPTIONS", path, handler)

                                                                  func (*Group) PATCH

                                                                  func (g *Group) PATCH(path string, handler HandlerFunc)

                                                                    Syntactic sugar for Handle("PATCH", path, handler)

                                                                    func (*Group) POST

                                                                    func (g *Group) POST(path string, handler HandlerFunc)

                                                                      Syntactic sugar for Handle("POST", path, handler)

                                                                      func (*Group) PUT

                                                                      func (g *Group) PUT(path string, handler HandlerFunc)

                                                                        Syntactic sugar for Handle("PUT", path, handler)

                                                                        func (*Group) UsingContext

                                                                        func (g *Group) UsingContext() *ContextGroup

                                                                          UsingContext wraps the receiver to return a new instance of a ContextGroup. The returned ContextGroup is a sibling to its wrapped Group, within the parent TreeMux. The choice of using a *Group as the receiver, as opposed to a function parameter, allows chaining while method calls between a TreeMux, Group, and ContextGroup. For example:

                                                                          tree := httptreemux.New()
                                                                          group := tree.NewGroup("/api")
                                                                          
                                                                          group.GET("/v1", func(w http.ResponseWriter, r *http.Request, params map[string]string) {
                                                                              w.Write([]byte(`GET /api/v1`))
                                                                          })
                                                                          
                                                                          group.UsingContext().GET("/v2", func(w http.ResponseWriter, r *http.Request) {
                                                                              w.Write([]byte(`GET /api/v2`))
                                                                          })
                                                                          
                                                                          http.ListenAndServe(":8080", tree)
                                                                          

                                                                          type HandlerFunc

                                                                          type HandlerFunc func(http.ResponseWriter, *http.Request, map[string]string)

                                                                            The params argument contains the parameters parsed from wildcards and catch-alls in the URL.

                                                                            type LookupResult

                                                                            type LookupResult struct {
                                                                            	// StatusCode informs the caller about the result of the lookup.
                                                                            	// This will generally be `http.StatusNotFound` or `http.StatusMethodNotAllowed` for an
                                                                            	// error case. On a normal success, the statusCode will be `http.StatusOK`. A redirect code
                                                                            	// will also be used in the case
                                                                            	StatusCode int
                                                                            	// contains filtered or unexported fields
                                                                            }

                                                                              LookupResult contains information about a route lookup, which is returned from Lookup and can be passed to ServeLookupResult if the request should be served.

                                                                              type PanicHandler

                                                                              type PanicHandler func(http.ResponseWriter, *http.Request, interface{})

                                                                              type PathSource

                                                                              type PathSource int

                                                                              type RedirectBehavior

                                                                              type RedirectBehavior int

                                                                                RedirectBehavior sets the behavior when the router redirects the request to the canonical version of the requested URL using RedirectTrailingSlash or RedirectClean. The default behavior is to return a 301 status, redirecting the browser to the version of the URL that matches the given pattern.

                                                                                On a POST request, most browsers that receive a 301 will submit a GET request to the redirected URL, meaning that any data will likely be lost. If you want to handle and avoid this behavior, you may use Redirect307, which causes most browsers to resubmit the request using the original method and request body.

                                                                                Since 307 is supposed to be a temporary redirect, the new 308 status code has been proposed, which is treated the same, except it indicates correctly that the redirection is permanent. The big caveat here is that the RFC is relatively recent, and older browsers will not know what to do with it. Therefore its use is not recommended unless you really know what you're doing.

                                                                                Finally, the UseHandler value will simply call the handler function for the pattern.

                                                                                type TreeMux

                                                                                type TreeMux struct {
                                                                                	Group
                                                                                
                                                                                	// The default PanicHandler just returns a 500 code.
                                                                                	PanicHandler PanicHandler
                                                                                
                                                                                	// The default NotFoundHandler is http.NotFound.
                                                                                	NotFoundHandler func(w http.ResponseWriter, r *http.Request)
                                                                                
                                                                                	// Any OPTIONS request that matches a path without its own OPTIONS handler will use this handler,
                                                                                	// if set, instead of calling MethodNotAllowedHandler.
                                                                                	OptionsHandler HandlerFunc
                                                                                
                                                                                	// MethodNotAllowedHandler is called when a pattern matches, but that
                                                                                	// pattern does not have a handler for the requested method. The default
                                                                                	// handler just writes the status code http.StatusMethodNotAllowed and adds
                                                                                	// the required Allowed header.
                                                                                	// The methods parameter contains the map of each method to the corresponding
                                                                                	// handler function.
                                                                                	MethodNotAllowedHandler func(w http.ResponseWriter, r *http.Request,
                                                                                		methods map[string]HandlerFunc)
                                                                                
                                                                                	// HeadCanUseGet allows the router to use the GET handler to respond to
                                                                                	// HEAD requests if no explicit HEAD handler has been added for the
                                                                                	// matching pattern. This is true by default.
                                                                                	HeadCanUseGet bool
                                                                                
                                                                                	// RedirectCleanPath allows the router to try clean the current request path,
                                                                                	// if no handler is registered for it, using CleanPath from github.com/dimfeld/httppath.
                                                                                	// This is true by default.
                                                                                	RedirectCleanPath bool
                                                                                
                                                                                	// RedirectTrailingSlash enables automatic redirection in case router doesn't find a matching route
                                                                                	// for the current request path but a handler for the path with or without the trailing
                                                                                	// slash exists. This is true by default.
                                                                                	RedirectTrailingSlash bool
                                                                                
                                                                                	// RemoveCatchAllTrailingSlash removes the trailing slash when a catch-all pattern
                                                                                	// is matched, if set to true. By default, catch-all paths are never redirected.
                                                                                	RemoveCatchAllTrailingSlash bool
                                                                                
                                                                                	// RedirectBehavior sets the default redirect behavior when RedirectTrailingSlash or
                                                                                	// RedirectCleanPath are true. The default value is Redirect301.
                                                                                	RedirectBehavior RedirectBehavior
                                                                                
                                                                                	// RedirectMethodBehavior overrides the default behavior for a particular HTTP method.
                                                                                	// The key is the method name, and the value is the behavior to use for that method.
                                                                                	RedirectMethodBehavior map[string]RedirectBehavior
                                                                                
                                                                                	// PathSource determines from where the router gets its path to search.
                                                                                	// By default it pulls the data from the RequestURI member, but this can
                                                                                	// be overridden to use URL.Path instead.
                                                                                	//
                                                                                	// There is a small tradeoff here. Using RequestURI allows the router to handle
                                                                                	// encoded slashes (i.e. %2f) in the URL properly, while URL.Path provides
                                                                                	// better compatibility with some utility functions in the http
                                                                                	// library that modify the Request before passing it to the router.
                                                                                	PathSource PathSource
                                                                                
                                                                                	// EscapeAddedRoutes controls URI escaping behavior when adding a route to the tree.
                                                                                	// If set to true, the router will add both the route as originally passed, and
                                                                                	// a version passed through URL.EscapedPath. This behavior is disabled by default.
                                                                                	EscapeAddedRoutes bool
                                                                                
                                                                                	// If present, override the default context with this one.
                                                                                	DefaultContext context.Context
                                                                                
                                                                                	// SafeAddRoutesWhileRunning tells the router to protect all accesses to the tree with an RWMutex. This is only needed
                                                                                	// if you are going to add routes after the router has already begun serving requests. There is a potential
                                                                                	// performance penalty at high load.
                                                                                	SafeAddRoutesWhileRunning bool
                                                                                	// contains filtered or unexported fields
                                                                                }

                                                                                func New

                                                                                func New() *TreeMux

                                                                                func (*TreeMux) Dump

                                                                                func (t *TreeMux) Dump() string

                                                                                  Dump returns a text representation of the routing tree.

                                                                                  func (*TreeMux) Lookup

                                                                                  func (t *TreeMux) Lookup(w http.ResponseWriter, r *http.Request) (LookupResult, bool)

                                                                                    Lookup performs a lookup without actually serving the request or mutating the request or response. The return values are a LookupResult and a boolean. The boolean will be true when a handler was found or the lookup resulted in a redirect which will point to a real handler. It is false for requests which would result in a `StatusNotFound` or `StatusMethodNotAllowed`.

                                                                                    Regardless of the returned boolean's value, the LookupResult may be passed to ServeLookupResult to be served appropriately.

                                                                                    func (*TreeMux) ServeHTTP

                                                                                    func (t *TreeMux) ServeHTTP(w http.ResponseWriter, r *http.Request)

                                                                                    func (*TreeMux) ServeLookupResult

                                                                                    func (t *TreeMux) ServeLookupResult(w http.ResponseWriter, r *http.Request, lr LookupResult)

                                                                                      ServeLookupResult serves a request, given a lookup result from the Lookup function.