treemux

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 Go to latest Published: Sep 11, 2021 License: MIT Imports: 8 Imported by: 7

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High-speed and flexible HTTP router for Go

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High-speed, flexible, tree-based HTTP router for Go. It is as fast as httprouter (if configured like httprouter for maximum performance, not correctness), but with relaxed routing rules.

Benchmark results 
#GithubAPI Routes: 203
   Gin: 58280 Bytes
   GorillaMux: 1319632 Bytes
   HttpRouter: 37088 Bytes
   UptraceTreemux: 52784 Bytes

#GPlusAPI Routes: 13
   Gin: 4376 Bytes
   GorillaMux: 66016 Bytes
   HttpRouter: 2760 Bytes
   UptraceTreemux: 5200 Bytes

#ParseAPI Routes: 26
   Gin: 7696 Bytes
   GorillaMux: 105448 Bytes
   HttpRouter: 5024 Bytes
   UptraceTreemux: 5248 Bytes

#Static Routes: 157
   Gin: 34488 Bytes
   GorillaMux: 582520 Bytes
   HttpRouter: 21680 Bytes
   UptraceTreemux: 44256 Bytes

goos: linux
goarch: amd64
pkg: github.com/julienschmidt/go-http-routing-benchmark
cpu: AMD Ryzen 5 2600 Six-Core Processor
BenchmarkGin_Param                       	13445883	        90.91 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_Param                	  497948	      2323 ns/op	    1312 B/op	      10 allocs/op
BenchmarkHttpRouter_Param                	11621246	       103.3 ns/op	      32 B/op	       1 allocs/op
BenchmarkUptraceTreemux_Param        	 8076144	       150.1 ns/op	      32 B/op	       1 allocs/op
BenchmarkGin_Param5                      	 7001068	       172.8 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_Param5               	  346927	      3547 ns/op	    1376 B/op	      10 allocs/op
BenchmarkHttpRouter_Param5               	 4407726	       271.0 ns/op	     160 B/op	       1 allocs/op
BenchmarkUptraceTreemux_Param5       	 2972869	       412.1 ns/op	     160 B/op	       1 allocs/op
BenchmarkGin_Param20                     	 3334362	       363.9 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_Param20              	  160214	      7475 ns/op	    3483 B/op	      12 allocs/op
BenchmarkHttpRouter_Param20              	 1375376	       834.6 ns/op	     640 B/op	       1 allocs/op
BenchmarkUptraceTreemux_Param20      	 1000000	      1415 ns/op	     640 B/op	       1 allocs/op
BenchmarkGin_ParamWrite                  	 6975416	       164.0 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_ParamWrite           	  476827	      2439 ns/op	    1312 B/op	      10 allocs/op
BenchmarkHttpRouter_ParamWrite           	 8530756	       139.6 ns/op	      32 B/op	       1 allocs/op
BenchmarkUptraceTreemux_ParamWrite   	 6340944	       187.2 ns/op	      32 B/op	       1 allocs/op
BenchmarkGin_GithubStatic                	11209341	       107.0 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GithubStatic         	  236701	      5205 ns/op	    1008 B/op	       9 allocs/op
BenchmarkHttpRouter_GithubStatic         	27611305	        43.33 ns/op	       0 B/op	       0 allocs/op
BenchmarkUptraceTreemux_GithubStatic 	19998584	        60.99 ns/op	       0 B/op	       0 allocs/op
BenchmarkGin_GithubParam                 	 5821226	       203.3 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GithubParam          	  146994	      7959 ns/op	    1328 B/op	      10 allocs/op
BenchmarkHttpRouter_GithubParam          	 5160134	       233.1 ns/op	      96 B/op	       1 allocs/op
BenchmarkUptraceTreemux_GithubParam  	 3622098	       331.1 ns/op	      64 B/op	       1 allocs/op
BenchmarkGin_GithubAll                   	   29200	     40809 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GithubAll            	     313	   3685931 ns/op	  258152 B/op	    1994 allocs/op
BenchmarkHttpRouter_GithubAll            	   26196	     47213 ns/op	   13792 B/op	     167 allocs/op
BenchmarkUptraceTreemux_GithubAll    	   20058	     59828 ns/op	   10848 B/op	     167 allocs/op
BenchmarkGin_GPlusStatic                 	13594092	        85.63 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GPlusStatic          	  637002	      1737 ns/op	    1008 B/op	       9 allocs/op
BenchmarkHttpRouter_GPlusStatic          	37554530	        29.70 ns/op	       0 B/op	       0 allocs/op
BenchmarkUptraceTreemux_GPlusStatic  	33921577	        34.39 ns/op	       0 B/op	       0 allocs/op
BenchmarkGin_GPlusParam                  	 8665750	       138.3 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GPlusParam           	  369037	      3147 ns/op	    1312 B/op	      10 allocs/op
BenchmarkHttpRouter_GPlusParam           	 7316545	       163.8 ns/op	      64 B/op	       1 allocs/op
BenchmarkUptraceTreemux_GPlusParam   	 6544346	       183.0 ns/op	      32 B/op	       1 allocs/op
BenchmarkGin_GPlus2Params                	 5480659	       215.5 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GPlus2Params         	  187828	      6270 ns/op	    1328 B/op	      10 allocs/op
BenchmarkHttpRouter_GPlus2Params         	 6125556	       193.1 ns/op	      64 B/op	       1 allocs/op
BenchmarkUptraceTreemux_GPlus2Params 	 3724188	       322.7 ns/op	      64 B/op	       1 allocs/op
BenchmarkGin_GPlusAll                    	  558418	      2137 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_GPlusAll             	   24033	     49393 ns/op	   16528 B/op	     128 allocs/op
BenchmarkHttpRouter_GPlusAll             	  600092	      2270 ns/op	     640 B/op	      11 allocs/op
BenchmarkUptraceTreemux_GPlusAll     	  387855	      2923 ns/op	     512 B/op	      11 allocs/op
BenchmarkGin_ParseStatic                 	13975424	        84.77 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_ParseStatic          	  556461	      2130 ns/op	    1008 B/op	       9 allocs/op
BenchmarkHttpRouter_ParseStatic          	43666348	        27.57 ns/op	       0 B/op	       0 allocs/op
BenchmarkUptraceTreemux_ParseStatic  	20183964	        59.89 ns/op	       0 B/op	       0 allocs/op
BenchmarkGin_ParseParam                  	11734768	       102.7 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_ParseParam           	  477866	      2429 ns/op	    1312 B/op	      10 allocs/op
BenchmarkHttpRouter_ParseParam           	 8223655	       146.3 ns/op	      64 B/op	       1 allocs/op
BenchmarkUptraceTreemux_ParseParam   	 7149213	       167.5 ns/op	      32 B/op	       1 allocs/op
BenchmarkGin_Parse2Params                	 9245916	       129.5 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_Parse2Params         	  396586	      3003 ns/op	    1328 B/op	      10 allocs/op
BenchmarkHttpRouter_Parse2Params         	 7201134	       168.7 ns/op	      64 B/op	       1 allocs/op
BenchmarkUptraceTreemux_Parse2Params 	 4365876	       273.0 ns/op	      64 B/op	       1 allocs/op
BenchmarkGin_ParseAll                    	  317048	      3631 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_ParseAll             	   12296	     96610 ns/op	   31120 B/op	     250 allocs/op
BenchmarkHttpRouter_ParseAll             	  398336	      3190 ns/op	     640 B/op	      16 allocs/op
BenchmarkUptraceTreemux_ParseAll     	  231426	      5115 ns/op	     608 B/op	      16 allocs/op
BenchmarkGin_StaticAll                   	   45273	     26511 ns/op	       0 B/op	       0 allocs/op
BenchmarkGorillaMux_StaticAll            	    1189	    973675 ns/op	  158261 B/op	    1413 allocs/op
BenchmarkHttpRouter_StaticAll            	   95552	     12534 ns/op	       0 B/op	       0 allocs/op
BenchmarkUptraceTreemux_StaticAll    	   69766	     17071 ns/op	       0 B/op	       0 allocs/op

Installing with Go Modules

When using Go Modules, import this repository with import "github.com/uptrace/treemux" to ensure that you get the right version.

Handler

treemux supports 2 types of handlers: treemux.HandlerFunc (recommended) and http.HandlerFunc.

The treemux handler is a simple function with the prototype func(w http.ResponseWriter, req treemux.Request) error. A treemux.Request contains route name and parameters parsed from wildcards and catch-alls in the URL.

The following example writes the route name and the param in JSON format:

import "github.com/uptrace/treemux"

router := treemux.New()

group := router.NewGroup("/api")

group.GET("/:id", func(w http.ResponseWriter, req treemux.Request) error {
  return treemux.JSON(w, treemux.H{
      "route": req.Route(),
      "id":    req.Param("id"),
  })
})

log.Println(http.ListenAndServe(":8888", router))

Alternatively, you can also use http.HandlerFunc:

import "github.com/uptrace/treemux"

router := treemux.New().Compat()

group := router.NewGroup("/api")

group.GET("/:id", func(w http.ResponseWriter, req *http.Request) {
  route := treemux.RouteFromContext(req.Context())
  _ = treemux.JSON(w, treemux.H{
      "route": route.Name(),
      "id":    route.Param("id"),
  })
})

log.Println(http.ListenAndServe(":8888", router))
Why treemux.HandlerFunc?

treemux.HandlerFunc is a thin wrapper over http.HandlerFunc:

  1. treemux.Request replaces *http.Request. You can get the original http.Request via req.Request.
  2. treemux.HandlerFunc returns errors just like other Go functions.

Those 2 tiny changes bring us:

  • Shorter and simpler error handling. In your handlers you just return the error and deal with it in a middleware in centralized fashion.
  • Easier debugging. Since middlewares have access to errors you can log errors along with other debugging information. OpenTelemetry integration uses that to record the error.
  • Route name and params. *http.Request was not designed to carry the route name and params. You can store that information in the request context.Context, but that clones the request and therefore requires an allocation
  • Efficiency. treemux.Request is designed so req.WithContext(ctx) does not allocate.

Treemux comes with middlewares that handle gzip compression, CORS, OpenTelemetry integration, and request logging. So with minimal changes you can work with existing libraries using treemux.HandlerFunc.

Converting http.HandlerFunc to treemux.HandlerFunc

treemux also provides helpers to convert existing http.HandlerFunc and http.Handler into treemux.HandlerFunc:

// http.HandlerFunc -> treemux.HandlerFunc
router.GET("/foo", treemux.HTTPHandlerFunc(existingHandlerFunc))

// http.Handler -> treemux.HandlerFunc
router.GET("/bar", treemux.HTTPHandler(existingHandler))

Then you can get the route information from the context:

route := treemux.RouteFromContext(req.Context())
fmt.Println(route.Name(), route.Params())

Middlewares

Middleware is a function that wraps a handler with another function:

func corsMiddleware(next treemux.HandlerFunc) treemux.HandlerFunc {
    return func(w http.ResponseWriter, req treemux.Request) error {
        if origin := req.Header.Get("Origin"); origin != "" {
            h := w.Header()
            h.Set("Access-Control-Allow-Origin", origin)
            h.Set("Access-Control-Allow-Credentials", "true")
        }
        return next(w, req)
    }
}

router := treemux.New(treemux.WithMiddleware(corsMiddleware))

Middlewares are also used for error handling.

Routing Rules

The syntax here is 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. A catch-all path will not match an empty string, so in this example a separate route would need to be installed if you also want to match /images/.

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 = treemux.New()

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

Or using WithGroup:

router.WithGroup("/api/v1", func(g *treemux.Group) {
    g.GET("/foo", fooHandler) // becomes /api/v1/foo
    g.GET("/bar", barHandler) // becomes /api/v1/bar
})

More complex example:

router := treemux.New()

g := router.NewGroup("/api/v1", treemux.WithMiddleware(ipRateLimitMiddleware))

g.NewGroup("/users/:user_id",
    treemux.WithMiddleware(authMiddleware),
    treemux.WithGroup(func(g *treemux.Group) {
        g.GET("", userHandler)

        g = g.WithMiddleware(adminMiddleware)

        g.PUT("", updateUserHandler)
        g.DELETE("", deleteUserHandler)
    }))

g.NewGroup("/projects/:project_id/articles/:article_id",
    treemux.WithMiddleware(authMiddleware),
    treemux.WithMiddleware(projectMiddleware),
    treemux.WithGroup(func(g *treemux.Group) {
        g.GET("", articleHandler)

        g.Use(quotaMiddleware)

        g.POST("", createArticleHandler)
        g.PUT("", updateArticleHandler)
        g.DELETE("", deleteArticleHandler)
    }))
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 = treemux.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.

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 = treemux.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.

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.

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.

httprouter and catch-all parameters

When using httprouter, a route with a catch-all parameter (e.g. /images/*path) will match on URLs like /images/ where the catch-all parameter is empty. This router does not match on empty catch-all parameters, but the behavior can be duplicated by adding a route without the catch-all (e.g. /images/).

httptreemux

treemux is a fork of httptreemux. The original code was written by Daniel Imfeld.

The following changes have been made:

  • Added a thin wrapper treemux.Request around http.Request to expose route via Request.Route and route params via Request.Params.
  • Setting context.Context does not require an allocation.
  • More efficient params encoding using a slice instead of a map.
  • Reworked configuration.
  • Group is immutable to avoid accidental middlewares leaking into parent groups.
  • treemux is 2-3 times faster.

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

This section is empty.

Variables

This section is empty.

Functions

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 JSON 

func JSON(w http.ResponseWriter, value interface{}) error

JSON marshals the value as JSON and writes it to the response writer.

Don't hesitate to copy-paste this function to your project and customize it as necessary.

func Version 

func Version() string

Version is the current release version.

Types

type CompatGroup 

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

CompatGroup is like Group, but it works with http.HandlerFunc instead of treemux handler.

func (CompatGroup) DELETE 

func (g CompatGroup) DELETE(path string, handler http.HandlerFunc)

func (CompatGroup) GET 

func (g CompatGroup) GET(path string, handler http.HandlerFunc)

func (CompatGroup) HEAD 

func (g CompatGroup) HEAD(path string, handler http.HandlerFunc)

func (CompatGroup) Handle 

func (g CompatGroup) Handle(method string, path string, handler http.HandlerFunc)

func (CompatGroup) NewGroup 

func (g CompatGroup) NewGroup(path string, opts ...GroupOption) *CompatGroup

func (CompatGroup) OPTIONS 

func (g CompatGroup) OPTIONS(path string, handler http.HandlerFunc)

func (CompatGroup) PATCH 

func (g CompatGroup) PATCH(path string, handler http.HandlerFunc)

func (CompatGroup) POST 

func (g CompatGroup) POST(path string, handler http.HandlerFunc)

func (CompatGroup) PUT 

func (g CompatGroup) PUT(path string, handler http.HandlerFunc)

func (CompatGroup) WithGroup 

func (g CompatGroup) WithGroup(path string, fn func(g *CompatGroup))

func (CompatGroup) WithMiddleware 

func (g CompatGroup) WithMiddleware(middleware MiddlewareFunc) *CompatGroup

type CompatRouter 

type CompatRouter struct {
	*Router
	*CompatGroup
}

type Group 

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

Group is a group of routes and middlewares.

func (*Group) Compat 

func (g *Group) Compat() *CompatGroup

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 = treemux.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 = treemux.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, opts ...GroupOption) *Group

NewGroup adds 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) WithGroup 

func (g *Group) WithGroup(path string, fn func(g *Group))

func (*Group) WithMiddleware 

func (g *Group) WithMiddleware(middleware MiddlewareFunc) *Group

type GroupOption 

type GroupOption interface {
	Option
	// contains filtered or unexported methods
}

func WithGroup 

func WithGroup(fn func(g *Group)) GroupOption

WithGroup calls the fn with the current Group.

func WithHandler 

func WithHandler(fn HandlerFunc) GroupOption

WithHandler is like WithMiddleware, but the handler can't modify the request.

func WithMiddleware 

func WithMiddleware(fn MiddlewareFunc) GroupOption

WithMiddleware adds a middleware handler to the Group's middleware stack.

type H 

type H map[string]interface{}

type HandlerFunc 

type HandlerFunc func(http.ResponseWriter, Request) error

func HTTPHandler 

func HTTPHandler(handler http.Handler) HandlerFunc

func HTTPHandlerFunc 

func HTTPHandlerFunc(handler http.HandlerFunc) HandlerFunc

type MiddlewareFunc 

type MiddlewareFunc func(next HandlerFunc) HandlerFunc

type Option 

type Option interface {
	// contains filtered or unexported methods
}

func UseURLPath 

func UseURLPath() Option

UseURLPath 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.

func WithHeadCanUseGet 

func WithHeadCanUseGet(on bool) Option

WithHeadCanUseGet 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.

func WithMethodNotAllowedHandler 

func WithMethodNotAllowedHandler(handler HandlerFunc) Option

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.

func WithNotFoundHandler 

func WithNotFoundHandler(handler HandlerFunc) Option

WithNotFoundHandler is called when there is no a matching pattern. The default NotFoundHandler is http.NotFound.

func WithRedirectBehavior 

func WithRedirectBehavior(value RedirectBehavior) Option

WithRedirectBehavior sets the default redirect behavior when RedirectTrailingSlash or RedirectCleanPath are true. The default value is Redirect301.

func WithRedirectCleanPath 

func WithRedirectCleanPath(on bool) Option

WithRedirectCleanPath 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.

func WithRedirectMethodBehavior 

func WithRedirectMethodBehavior(value map[string]RedirectBehavior) Option

WithRedirectMethodBehavior 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.

func WithRedirectTrailingSlash 

func WithRedirectTrailingSlash(on bool) Option

WithRedirectTrailingSlash 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.

func WithRemoveCatchAllTrailingSlash 

func WithRemoveCatchAllTrailingSlash(on bool) Option

WithRemoveCatchAllTrailingSlash removes the trailing slash when a catch-all pattern is matched, if set to true. By default, catch-all paths are never redirected.

type Param 

type Param struct {
	Name  string
	Value string
}

type Params 

type Params []Param

func (Params) Get 

func (ps Params) Get(name string) (string, bool)

func (Params) Int32 

func (ps Params) Int32(name string) (int32, error)

func (Params) Int64 

func (ps Params) Int64(name string) (int64, error)

func (Params) Map 

func (ps Params) Map() map[string]string

func (Params) Text 

func (ps Params) Text(name string) string

func (Params) Uint32 

func (ps Params) Uint32(name string) (uint32, error)

func (Params) Uint64 

func (ps Params) Uint64(name string) (uint64, error)

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. 

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
)

type Request 

type Request struct {
	*http.Request
	// contains filtered or unexported fields
}

func NewRequest 

func NewRequest(req *http.Request) Request

func (Request) Context 

func (req Request) Context() context.Context

func (Request) Param 

func (req Request) Param(key string) string

func (Request) Params 

func (req Request) Params() Params

func (Request) Route 

func (req Request) Route() string

func (Request) WithContext 

func (req Request) WithContext(ctx context.Context) Request

func (Request) WithParams 

func (req Request) WithParams(params Params) Request

type RouteInfo 

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

func RouteFromContext 

func RouteFromContext(ctx context.Context) *RouteInfo

func (*RouteInfo) Name 

func (r *RouteInfo) Name() string

func (*RouteInfo) Param 

func (r *RouteInfo) Param(name string) string

func (*RouteInfo) Params 

func (r *RouteInfo) Params() Params

type Router 

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

func New 

func New(opts ...Option) *Router

func (*Router) Compat 

func (r *Router) Compat() *CompatRouter

func (*Router) Dump 

func (t *Router) Dump() string

Dump returns a text representation of the routing tree.

func (*Router) ServeHTTP 

func (t *Router) ServeHTTP(w http.ResponseWriter, req *http.Request)

Source Files

View all Source files

Directories

Path Synopsis
example
basic Module
basic-compat Module
error-handling Module
rate-limiting Module
extra
reqlog Module
treemuxgzip Module
treemuxotel Module

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