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diff --git a/vendor/github.com/gorilla/mux/README.md b/vendor/github.com/gorilla/mux/README.md new file mode 100644 index 0000000..67a79e0 --- /dev/null +++ b/vendor/github.com/gorilla/mux/README.md @@ -0,0 +1,415 @@ +gorilla/mux +=== +[](https://godoc.org/github.com/gorilla/mux) +[](https://travis-ci.org/gorilla/mux) +[](https://sourcegraph.com/github.com/gorilla/mux?badge) + + + +http://www.gorillatoolkit.org/pkg/mux + +Package `gorilla/mux` implements a request router and dispatcher for matching incoming requests to +their respective handler. + +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: + +* It implements the `http.Handler` interface so it is compatible with the standard `http.ServeMux`. +* Requests can be matched based on URL host, path, path prefix, schemes, header and query values, HTTP methods or using custom matchers. +* URL hosts, paths and query values 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. + +--- + +* [Install](#install) +* [Examples](#examples) +* [Matching Routes](#matching-routes) +* [Static Files](#static-files) +* [Registered URLs](#registered-urls) +* [Walking Routes](#walking-routes) +* [Full Example](#full-example) + +--- + +## Install + +With a [correctly configured](https://golang.org/doc/install#testing) Go toolchain: + +```sh +go get -u github.com/gorilla/mux +``` + +## Examples + +Let's start registering a couple of URL paths and handlers: + +```go +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: + +```go +r := mux.NewRouter() +r.HandleFunc("/products/{key}", ProductHandler) +r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler) +r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler) +``` + +The names are used to create a map of route variables which can be retrieved calling `mux.Vars()`: + +```go +func ArticlesCategoryHandler(w http.ResponseWriter, r *http.Request) { + vars := mux.Vars(r) + w.WriteHeader(http.StatusOK) + fmt.Fprintf(w, "Category: %v\n", vars["category"]) +} +``` + +And this is all you need to know about the basic usage. More advanced options are explained below. + +### Matching Routes + +Routes can also be restricted to a domain or subdomain. Just define a host pattern to be matched. They can also have variables: + +```go +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: + +```go +r.PathPrefix("/products/") +``` + +...or HTTP methods: + +```go +r.Methods("GET", "POST") +``` + +...or URL schemes: + +```go +r.Schemes("https") +``` + +...or header values: + +```go +r.Headers("X-Requested-With", "XMLHttpRequest") +``` + +...or query values: + +```go +r.Queries("key", "value") +``` + +...or to use a custom matcher function: + +```go +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: + +```go +r.HandleFunc("/products", ProductsHandler). + Host("www.example.com"). + Methods("GET"). + Schemes("http") +``` + +Routes are tested in the order they were added to the router. If two routes match, the first one wins: + +```go +r := mux.NewRouter() +r.HandleFunc("/specific", specificHandler) +r.PathPrefix("/").Handler(catchAllHandler) +``` + +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: + +```go +r := mux.NewRouter() +s := r.Host("www.example.com").Subrouter() +``` + +Then register routes in the subrouter: + +```go +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: + +```go +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) +``` +### Listing Routes + +Routes on a mux can be listed using the Router.Walk method—useful for generating documentation: + +```go +package main + +import ( + "fmt" + "net/http" + "strings" + + "github.com/gorilla/mux" +) + +func handler(w http.ResponseWriter, r *http.Request) { + return +} + +func main() { + r := mux.NewRouter() + r.HandleFunc("/", handler) + r.HandleFunc("/products", handler).Methods("POST") + r.HandleFunc("/articles", handler).Methods("GET") + r.HandleFunc("/articles/{id}", handler).Methods("GET", "PUT") + r.HandleFunc("/authors", handler).Queries("surname", "{surname}") + r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error { + t, err := route.GetPathTemplate() + if err != nil { + return err + } + qt, err := route.GetQueriesTemplates() + if err != nil { + return err + } + // p will contain regular expression is compatible with regular expression in Perl, Python, and other languages. + // for instance the regular expression for path '/articles/{id}' will be '^/articles/(?P<v0>[^/]+)$' + p, err := route.GetPathRegexp() + if err != nil { + return err + } + // qr will contain a list of regular expressions with the same semantics as GetPathRegexp, + // just applied to the Queries pairs instead, e.g., 'Queries("surname", "{surname}") will return + // {"^surname=(?P<v0>.*)$}. Where each combined query pair will have an entry in the list. + qr, err := route.GetQueriesRegexp() + if err != nil { + return err + } + m, err := route.GetMethods() + if err != nil { + return err + } + fmt.Println(strings.Join(m, ","), strings.Join(qt, ","), strings.Join(qr, ","), t, p) + return nil + }) + http.Handle("/", r) +} +``` + +### Static Files + +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: + +```go +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()) +} +``` + +### Registered URLs + +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: + +```go +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: + +```go +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 and query value variables: + +```go +r := mux.NewRouter() +r.Host("{subdomain}.domain.com"). + Path("/articles/{category}/{id:[0-9]+}"). + Queries("filter", "{filter}"). + HandlerFunc(ArticleHandler). + Name("article") + +// url.String() will be "http://news.domain.com/articles/technology/42?filter=gorilla" +url, err := r.Get("article").URL("subdomain", "news", + "category", "technology", + "id", "42", + "filter", "gorilla") +``` + +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: + +```go +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: + +```go +// "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: + +```go +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") +``` + +### Walking Routes + +The `Walk` function on `mux.Router` can be used to visit all of the routes that are registered on a router. For example, +the following prints all of the registered routes: + +```go +r := mux.NewRouter() +r.HandleFunc("/", handler) +r.HandleFunc("/products", handler).Methods("POST") +r.HandleFunc("/articles", handler).Methods("GET") +r.HandleFunc("/articles/{id}", handler).Methods("GET", "PUT") +r.HandleFunc("/authors", handler).Queries("surname", "{surname}") +r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error { + t, err := route.GetPathTemplate() + if err != nil { + return err + } + qt, err := route.GetQueriesTemplates() + if err != nil { + return err + } + // p will contain a regular expression that is compatible with regular expressions in Perl, Python, and other languages. + // For example, the regular expression for path '/articles/{id}' will be '^/articles/(?P<v0>[^/]+)$'. + p, err := route.GetPathRegexp() + if err != nil { + return err + } + // qr will contain a list of regular expressions with the same semantics as GetPathRegexp, + // just applied to the Queries pairs instead, e.g., 'Queries("surname", "{surname}") will return + // {"^surname=(?P<v0>.*)$}. Where each combined query pair will have an entry in the list. + qr, err := route.GetQueriesRegexp() + if err != nil { + return err + } + m, err := route.GetMethods() + if err != nil { + return err + } + fmt.Println(strings.Join(m, ","), strings.Join(qt, ","), strings.Join(qr, ","), t, p) + return nil +}) +``` + +## Full Example + +Here's a complete, runnable example of a small `mux` based server: + +```go +package main + +import ( + "net/http" + "log" + "github.com/gorilla/mux" +) + +func YourHandler(w http.ResponseWriter, r *http.Request) { + w.Write([]byte("Gorilla!\n")) +} + +func main() { + r := mux.NewRouter() + // Routes consist of a path and a handler function. + r.HandleFunc("/", YourHandler) + + // Bind to a port and pass our router in + log.Fatal(http.ListenAndServe(":8000", r)) +} +``` + +## License + +BSD licensed. See the LICENSE file for details. |