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diff --git a/vendor/github.com/gorilla/mux/doc.go b/vendor/github.com/gorilla/mux/doc.go new file mode 100644 index 000000000..00daf4a72 --- /dev/null +++ b/vendor/github.com/gorilla/mux/doc.go @@ -0,0 +1,240 @@ +// Copyright 2012 The Gorilla Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* +Package mux implements a request router and dispatcher. + +The name mux stands for "HTTP request multiplexer". Like the standard +http.ServeMux, mux.Router matches incoming requests against a list of +registered routes and calls a handler for the route that matches the URL +or other conditions. The main features are: + + * Requests can be matched based on URL host, path, path prefix, schemes, + header and query values, HTTP methods or using custom matchers. + * URL hosts and paths can have variables with an optional regular + expression. + * Registered URLs can be built, or "reversed", which helps maintaining + references to resources. + * Routes can be used as subrouters: nested routes are only tested if the + parent route matches. This is useful to define groups of routes that + share common conditions like a host, a path prefix or other repeated + attributes. As a bonus, this optimizes request matching. + * It implements the http.Handler interface so it is compatible with the + standard http.ServeMux. + +Let's start registering a couple of URL paths and handlers: + + func main() { + r := mux.NewRouter() + r.HandleFunc("/", HomeHandler) + r.HandleFunc("/products", ProductsHandler) + r.HandleFunc("/articles", ArticlesHandler) + http.Handle("/", r) + } + +Here we register three routes mapping URL paths to handlers. This is +equivalent to how http.HandleFunc() works: if an incoming request URL matches +one of the paths, the corresponding handler is called passing +(http.ResponseWriter, *http.Request) as parameters. + +Paths can have variables. They are defined using the format {name} or +{name:pattern}. If a regular expression pattern is not defined, the matched +variable will be anything until the next slash. For example: + + r := mux.NewRouter() + r.HandleFunc("/products/{key}", ProductHandler) + r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler) + r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler) + +Groups can be used inside patterns, as long as they are non-capturing (?:re). For example: + + r.HandleFunc("/articles/{category}/{sort:(?:asc|desc|new)}", ArticlesCategoryHandler) + +The names are used to create a map of route variables which can be retrieved +calling mux.Vars(): + + vars := mux.Vars(request) + category := vars["category"] + +Note that if any capturing groups are present, mux will panic() during parsing. To prevent +this, convert any capturing groups to non-capturing, e.g. change "/{sort:(asc|desc)}" to +"/{sort:(?:asc|desc)}". This is a change from prior versions which behaved unpredictably +when capturing groups were present. + +And this is all you need to know about the basic usage. More advanced options +are explained below. + +Routes can also be restricted to a domain or subdomain. Just define a host +pattern to be matched. They can also have variables: + + r := mux.NewRouter() + // Only matches if domain is "www.example.com". + r.Host("www.example.com") + // Matches a dynamic subdomain. + r.Host("{subdomain:[a-z]+}.domain.com") + +There are several other matchers that can be added. To match path prefixes: + + r.PathPrefix("/products/") + +...or HTTP methods: + + r.Methods("GET", "POST") + +...or URL schemes: + + r.Schemes("https") + +...or header values: + + r.Headers("X-Requested-With", "XMLHttpRequest") + +...or query values: + + r.Queries("key", "value") + +...or to use a custom matcher function: + + r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool { + return r.ProtoMajor == 0 + }) + +...and finally, it is possible to combine several matchers in a single route: + + r.HandleFunc("/products", ProductsHandler). + Host("www.example.com"). + Methods("GET"). + Schemes("http") + +Setting the same matching conditions again and again can be boring, so we have +a way to group several routes that share the same requirements. +We call it "subrouting". + +For example, let's say we have several URLs that should only match when the +host is "www.example.com". Create a route for that host and get a "subrouter" +from it: + + r := mux.NewRouter() + s := r.Host("www.example.com").Subrouter() + +Then register routes in the subrouter: + + s.HandleFunc("/products/", ProductsHandler) + s.HandleFunc("/products/{key}", ProductHandler) + s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler) + +The three URL paths we registered above will only be tested if the domain is +"www.example.com", because the subrouter is tested first. This is not +only convenient, but also optimizes request matching. You can create +subrouters combining any attribute matchers accepted by a route. + +Subrouters can be used to create domain or path "namespaces": you define +subrouters in a central place and then parts of the app can register its +paths relatively to a given subrouter. + +There's one more thing about subroutes. When a subrouter has a path prefix, +the inner routes use it as base for their paths: + + r := mux.NewRouter() + s := r.PathPrefix("/products").Subrouter() + // "/products/" + s.HandleFunc("/", ProductsHandler) + // "/products/{key}/" + s.HandleFunc("/{key}/", ProductHandler) + // "/products/{key}/details" + s.HandleFunc("/{key}/details", ProductDetailsHandler) + +Note that the path provided to PathPrefix() represents a "wildcard": calling +PathPrefix("/static/").Handler(...) means that the handler will be passed any +request that matches "/static/*". This makes it easy to serve static files with mux: + + func main() { + var dir string + + flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir") + flag.Parse() + r := mux.NewRouter() + + // This will serve files under http://localhost:8000/static/<filename> + r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir)))) + + srv := &http.Server{ + Handler: r, + Addr: "127.0.0.1:8000", + // Good practice: enforce timeouts for servers you create! + WriteTimeout: 15 * time.Second, + ReadTimeout: 15 * time.Second, + } + + log.Fatal(srv.ListenAndServe()) + } + +Now let's see how to build registered URLs. + +Routes can be named. All routes that define a name can have their URLs built, +or "reversed". We define a name calling Name() on a route. For example: + + r := mux.NewRouter() + r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler). + Name("article") + +To build a URL, get the route and call the URL() method, passing a sequence of +key/value pairs for the route variables. For the previous route, we would do: + + url, err := r.Get("article").URL("category", "technology", "id", "42") + +...and the result will be a url.URL with the following path: + + "/articles/technology/42" + +This also works for host variables: + + r := mux.NewRouter() + r.Host("{subdomain}.domain.com"). + Path("/articles/{category}/{id:[0-9]+}"). + HandlerFunc(ArticleHandler). + Name("article") + + // url.String() will be "http://news.domain.com/articles/technology/42" + url, err := r.Get("article").URL("subdomain", "news", + "category", "technology", + "id", "42") + +All variables defined in the route are required, and their values must +conform to the corresponding patterns. These requirements guarantee that a +generated URL will always match a registered route -- the only exception is +for explicitly defined "build-only" routes which never match. + +Regex support also exists for matching Headers within a route. For example, we could do: + + r.HeadersRegexp("Content-Type", "application/(text|json)") + +...and the route will match both requests with a Content-Type of `application/json` as well as +`application/text` + +There's also a way to build only the URL host or path for a route: +use the methods URLHost() or URLPath() instead. For the previous route, +we would do: + + // "http://news.domain.com/" + host, err := r.Get("article").URLHost("subdomain", "news") + + // "/articles/technology/42" + path, err := r.Get("article").URLPath("category", "technology", "id", "42") + +And if you use subrouters, host and path defined separately can be built +as well: + + r := mux.NewRouter() + s := r.Host("{subdomain}.domain.com").Subrouter() + s.Path("/articles/{category}/{id:[0-9]+}"). + HandlerFunc(ArticleHandler). + Name("article") + + // "http://news.domain.com/articles/technology/42" + url, err := r.Get("article").URL("subdomain", "news", + "category", "technology", + "id", "42") +*/ +package mux |