Add initial code for sadis-server.

Change-Id: Iaa8d6ddf888c04abc8eee5933c0c7401c0094394
diff --git a/vendor/github.com/gorilla/mux/LICENSE b/vendor/github.com/gorilla/mux/LICENSE
new file mode 100644
index 0000000..0e5fb87
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2012 Rodrigo Moraes. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/gorilla/mux/README.md b/vendor/github.com/gorilla/mux/README.md
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index 0000000..94d396c
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+++ b/vendor/github.com/gorilla/mux/README.md
@@ -0,0 +1,339 @@
+gorilla/mux
+===
+[![GoDoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
+[![Build Status](https://travis-ci.org/gorilla/mux.svg?branch=master)](https://travis-ci.org/gorilla/mux)
+
+![Gorilla Logo](http://www.gorillatoolkit.org/static/images/gorilla-icon-64.png)
+
+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 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.
+
+---
+
+* [Install](#install)
+* [Examples](#examples)
+* [Matching Routes](#matching-routes)
+* [Listing Routes](#listing-routes)
+* [Static Files](#static-files)
+* [Registered URLs](#registered-urls)
+* [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")
+```
+
+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"
+
+    "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)
+    r.HandleFunc("/articles", handler)
+    r.HandleFunc("/articles/{id}", handler)
+    r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error {
+        t, err := route.GetPathTemplate()
+        if err != nil {
+            return err
+        }
+        fmt.Println(t)
+        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 variables:
+
+```go
+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:
+
+```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")
+```
+
+## 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.
diff --git a/vendor/github.com/gorilla/mux/context_gorilla.go b/vendor/github.com/gorilla/mux/context_gorilla.go
new file mode 100644
index 0000000..d7adaa8
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/context_gorilla.go
@@ -0,0 +1,26 @@
+// +build !go1.7
+
+package mux
+
+import (
+	"net/http"
+
+	"github.com/gorilla/context"
+)
+
+func contextGet(r *http.Request, key interface{}) interface{} {
+	return context.Get(r, key)
+}
+
+func contextSet(r *http.Request, key, val interface{}) *http.Request {
+	if val == nil {
+		return r
+	}
+
+	context.Set(r, key, val)
+	return r
+}
+
+func contextClear(r *http.Request) {
+	context.Clear(r)
+}
diff --git a/vendor/github.com/gorilla/mux/context_native.go b/vendor/github.com/gorilla/mux/context_native.go
new file mode 100644
index 0000000..209cbea
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/context_native.go
@@ -0,0 +1,24 @@
+// +build go1.7
+
+package mux
+
+import (
+	"context"
+	"net/http"
+)
+
+func contextGet(r *http.Request, key interface{}) interface{} {
+	return r.Context().Value(key)
+}
+
+func contextSet(r *http.Request, key, val interface{}) *http.Request {
+	if val == nil {
+		return r
+	}
+
+	return r.WithContext(context.WithValue(r.Context(), key, val))
+}
+
+func contextClear(r *http.Request) {
+	return
+}
diff --git a/vendor/github.com/gorilla/mux/doc.go b/vendor/github.com/gorilla/mux/doc.go
new file mode 100644
index 0000000..00daf4a
--- /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
diff --git a/vendor/github.com/gorilla/mux/mux.go b/vendor/github.com/gorilla/mux/mux.go
new file mode 100644
index 0000000..d66ec38
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/mux.go
@@ -0,0 +1,542 @@
+// 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
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"path"
+	"regexp"
+	"strings"
+)
+
+// NewRouter returns a new router instance.
+func NewRouter() *Router {
+	return &Router{namedRoutes: make(map[string]*Route), KeepContext: false}
+}
+
+// Router registers routes to be matched and dispatches a handler.
+//
+// It implements the http.Handler interface, so it can be registered to serve
+// requests:
+//
+//     var router = mux.NewRouter()
+//
+//     func main() {
+//         http.Handle("/", router)
+//     }
+//
+// Or, for Google App Engine, register it in a init() function:
+//
+//     func init() {
+//         http.Handle("/", router)
+//     }
+//
+// This will send all incoming requests to the router.
+type Router struct {
+	// Configurable Handler to be used when no route matches.
+	NotFoundHandler http.Handler
+	// Parent route, if this is a subrouter.
+	parent parentRoute
+	// Routes to be matched, in order.
+	routes []*Route
+	// Routes by name for URL building.
+	namedRoutes map[string]*Route
+	// See Router.StrictSlash(). This defines the flag for new routes.
+	strictSlash bool
+	// See Router.SkipClean(). This defines the flag for new routes.
+	skipClean bool
+	// If true, do not clear the request context after handling the request.
+	// This has no effect when go1.7+ is used, since the context is stored
+	// on the request itself.
+	KeepContext bool
+	// see Router.UseEncodedPath(). This defines a flag for all routes.
+	useEncodedPath bool
+}
+
+// Match matches registered routes against the request.
+func (r *Router) Match(req *http.Request, match *RouteMatch) bool {
+	for _, route := range r.routes {
+		if route.Match(req, match) {
+			return true
+		}
+	}
+
+	// Closest match for a router (includes sub-routers)
+	if r.NotFoundHandler != nil {
+		match.Handler = r.NotFoundHandler
+		return true
+	}
+	return false
+}
+
+// ServeHTTP dispatches the handler registered in the matched route.
+//
+// When there is a match, the route variables can be retrieved calling
+// mux.Vars(request).
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if !r.skipClean {
+		path := req.URL.Path
+		if r.useEncodedPath {
+			path = getPath(req)
+		}
+		// Clean path to canonical form and redirect.
+		if p := cleanPath(path); p != path {
+
+			// Added 3 lines (Philip Schlump) - It was dropping the query string and #whatever from query.
+			// This matches with fix in go 1.2 r.c. 4 for same problem.  Go Issue:
+			// http://code.google.com/p/go/issues/detail?id=5252
+			url := *req.URL
+			url.Path = p
+			p = url.String()
+
+			w.Header().Set("Location", p)
+			w.WriteHeader(http.StatusMovedPermanently)
+			return
+		}
+	}
+	var match RouteMatch
+	var handler http.Handler
+	if r.Match(req, &match) {
+		handler = match.Handler
+		req = setVars(req, match.Vars)
+		req = setCurrentRoute(req, match.Route)
+	}
+	if handler == nil {
+		handler = http.NotFoundHandler()
+	}
+	if !r.KeepContext {
+		defer contextClear(req)
+	}
+	handler.ServeHTTP(w, req)
+}
+
+// Get returns a route registered with the given name.
+func (r *Router) Get(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// GetRoute returns a route registered with the given name. This method
+// was renamed to Get() and remains here for backwards compatibility.
+func (r *Router) GetRoute(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// StrictSlash defines the trailing slash behavior for new routes. The initial
+// value is false.
+//
+// When true, if the route path is "/path/", accessing "/path" will redirect
+// to the former and vice versa. In other words, your application will always
+// see the path as specified in the route.
+//
+// When false, if the route path is "/path", accessing "/path/" will not match
+// this route and vice versa.
+//
+// Special case: when a route sets a path prefix using the PathPrefix() method,
+// strict slash is ignored for that route because the redirect behavior can't
+// be determined from a prefix alone. However, any subrouters created from that
+// route inherit the original StrictSlash setting.
+func (r *Router) StrictSlash(value bool) *Router {
+	r.strictSlash = value
+	return r
+}
+
+// SkipClean defines the path cleaning behaviour for new routes. The initial
+// value is false. Users should be careful about which routes are not cleaned
+//
+// When true, if the route path is "/path//to", it will remain with the double
+// slash. This is helpful if you have a route like: /fetch/http://xkcd.com/534/
+//
+// When false, the path will be cleaned, so /fetch/http://xkcd.com/534/ will
+// become /fetch/http/xkcd.com/534
+func (r *Router) SkipClean(value bool) *Router {
+	r.skipClean = value
+	return r
+}
+
+// UseEncodedPath tells the router to match the encoded original path
+// to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/{var}/to".
+// This behavior has the drawback of needing to match routes against
+// r.RequestURI instead of r.URL.Path. Any modifications (such as http.StripPrefix)
+// to r.URL.Path will not affect routing when this flag is on and thus may
+// induce unintended behavior.
+//
+// If not called, the router will match the unencoded path to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/foo/bar/to"
+func (r *Router) UseEncodedPath() *Router {
+	r.useEncodedPath = true
+	return r
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Router) getNamedRoutes() map[string]*Route {
+	if r.namedRoutes == nil {
+		if r.parent != nil {
+			r.namedRoutes = r.parent.getNamedRoutes()
+		} else {
+			r.namedRoutes = make(map[string]*Route)
+		}
+	}
+	return r.namedRoutes
+}
+
+// getRegexpGroup returns regexp definitions from the parent route, if any.
+func (r *Router) getRegexpGroup() *routeRegexpGroup {
+	if r.parent != nil {
+		return r.parent.getRegexpGroup()
+	}
+	return nil
+}
+
+func (r *Router) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// Route factories
+// ----------------------------------------------------------------------------
+
+// NewRoute registers an empty route.
+func (r *Router) NewRoute() *Route {
+	route := &Route{parent: r, strictSlash: r.strictSlash, skipClean: r.skipClean, useEncodedPath: r.useEncodedPath}
+	r.routes = append(r.routes, route)
+	return route
+}
+
+// Handle registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.Handler().
+func (r *Router) Handle(path string, handler http.Handler) *Route {
+	return r.NewRoute().Path(path).Handler(handler)
+}
+
+// HandleFunc registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.HandlerFunc().
+func (r *Router) HandleFunc(path string, f func(http.ResponseWriter,
+	*http.Request)) *Route {
+	return r.NewRoute().Path(path).HandlerFunc(f)
+}
+
+// Headers registers a new route with a matcher for request header values.
+// See Route.Headers().
+func (r *Router) Headers(pairs ...string) *Route {
+	return r.NewRoute().Headers(pairs...)
+}
+
+// Host registers a new route with a matcher for the URL host.
+// See Route.Host().
+func (r *Router) Host(tpl string) *Route {
+	return r.NewRoute().Host(tpl)
+}
+
+// MatcherFunc registers a new route with a custom matcher function.
+// See Route.MatcherFunc().
+func (r *Router) MatcherFunc(f MatcherFunc) *Route {
+	return r.NewRoute().MatcherFunc(f)
+}
+
+// Methods registers a new route with a matcher for HTTP methods.
+// See Route.Methods().
+func (r *Router) Methods(methods ...string) *Route {
+	return r.NewRoute().Methods(methods...)
+}
+
+// Path registers a new route with a matcher for the URL path.
+// See Route.Path().
+func (r *Router) Path(tpl string) *Route {
+	return r.NewRoute().Path(tpl)
+}
+
+// PathPrefix registers a new route with a matcher for the URL path prefix.
+// See Route.PathPrefix().
+func (r *Router) PathPrefix(tpl string) *Route {
+	return r.NewRoute().PathPrefix(tpl)
+}
+
+// Queries registers a new route with a matcher for URL query values.
+// See Route.Queries().
+func (r *Router) Queries(pairs ...string) *Route {
+	return r.NewRoute().Queries(pairs...)
+}
+
+// Schemes registers a new route with a matcher for URL schemes.
+// See Route.Schemes().
+func (r *Router) Schemes(schemes ...string) *Route {
+	return r.NewRoute().Schemes(schemes...)
+}
+
+// BuildVarsFunc registers a new route with a custom function for modifying
+// route variables before building a URL.
+func (r *Router) BuildVarsFunc(f BuildVarsFunc) *Route {
+	return r.NewRoute().BuildVarsFunc(f)
+}
+
+// Walk walks the router and all its sub-routers, calling walkFn for each route
+// in the tree. The routes are walked in the order they were added. Sub-routers
+// are explored depth-first.
+func (r *Router) Walk(walkFn WalkFunc) error {
+	return r.walk(walkFn, []*Route{})
+}
+
+// SkipRouter is used as a return value from WalkFuncs to indicate that the
+// router that walk is about to descend down to should be skipped.
+var SkipRouter = errors.New("skip this router")
+
+// WalkFunc is the type of the function called for each route visited by Walk.
+// At every invocation, it is given the current route, and the current router,
+// and a list of ancestor routes that lead to the current route.
+type WalkFunc func(route *Route, router *Router, ancestors []*Route) error
+
+func (r *Router) walk(walkFn WalkFunc, ancestors []*Route) error {
+	for _, t := range r.routes {
+		if t.regexp == nil || t.regexp.path == nil || t.regexp.path.template == "" {
+			continue
+		}
+
+		err := walkFn(t, r, ancestors)
+		if err == SkipRouter {
+			continue
+		}
+		if err != nil {
+			return err
+		}
+		for _, sr := range t.matchers {
+			if h, ok := sr.(*Router); ok {
+				err := h.walk(walkFn, ancestors)
+				if err != nil {
+					return err
+				}
+			}
+		}
+		if h, ok := t.handler.(*Router); ok {
+			ancestors = append(ancestors, t)
+			err := h.walk(walkFn, ancestors)
+			if err != nil {
+				return err
+			}
+			ancestors = ancestors[:len(ancestors)-1]
+		}
+	}
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Context
+// ----------------------------------------------------------------------------
+
+// RouteMatch stores information about a matched route.
+type RouteMatch struct {
+	Route   *Route
+	Handler http.Handler
+	Vars    map[string]string
+}
+
+type contextKey int
+
+const (
+	varsKey contextKey = iota
+	routeKey
+)
+
+// Vars returns the route variables for the current request, if any.
+func Vars(r *http.Request) map[string]string {
+	if rv := contextGet(r, varsKey); rv != nil {
+		return rv.(map[string]string)
+	}
+	return nil
+}
+
+// CurrentRoute returns the matched route for the current request, if any.
+// This only works when called inside the handler of the matched route
+// because the matched route is stored in the request context which is cleared
+// after the handler returns, unless the KeepContext option is set on the
+// Router.
+func CurrentRoute(r *http.Request) *Route {
+	if rv := contextGet(r, routeKey); rv != nil {
+		return rv.(*Route)
+	}
+	return nil
+}
+
+func setVars(r *http.Request, val interface{}) *http.Request {
+	return contextSet(r, varsKey, val)
+}
+
+func setCurrentRoute(r *http.Request, val interface{}) *http.Request {
+	return contextSet(r, routeKey, val)
+}
+
+// ----------------------------------------------------------------------------
+// Helpers
+// ----------------------------------------------------------------------------
+
+// getPath returns the escaped path if possible; doing what URL.EscapedPath()
+// which was added in go1.5 does
+func getPath(req *http.Request) string {
+	if req.RequestURI != "" {
+		// Extract the path from RequestURI (which is escaped unlike URL.Path)
+		// as detailed here as detailed in https://golang.org/pkg/net/url/#URL
+		// for < 1.5 server side workaround
+		// http://localhost/path/here?v=1 -> /path/here
+		path := req.RequestURI
+		path = strings.TrimPrefix(path, req.URL.Scheme+`://`)
+		path = strings.TrimPrefix(path, req.URL.Host)
+		if i := strings.LastIndex(path, "?"); i > -1 {
+			path = path[:i]
+		}
+		if i := strings.LastIndex(path, "#"); i > -1 {
+			path = path[:i]
+		}
+		return path
+	}
+	return req.URL.Path
+}
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+// Borrowed from the net/http package.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+
+	return np
+}
+
+// uniqueVars returns an error if two slices contain duplicated strings.
+func uniqueVars(s1, s2 []string) error {
+	for _, v1 := range s1 {
+		for _, v2 := range s2 {
+			if v1 == v2 {
+				return fmt.Errorf("mux: duplicated route variable %q", v2)
+			}
+		}
+	}
+	return nil
+}
+
+// checkPairs returns the count of strings passed in, and an error if
+// the count is not an even number.
+func checkPairs(pairs ...string) (int, error) {
+	length := len(pairs)
+	if length%2 != 0 {
+		return length, fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+	}
+	return length, nil
+}
+
+// mapFromPairsToString converts variadic string parameters to a
+// string to string map.
+func mapFromPairsToString(pairs ...string) (map[string]string, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]string, length/2)
+	for i := 0; i < length; i += 2 {
+		m[pairs[i]] = pairs[i+1]
+	}
+	return m, nil
+}
+
+// mapFromPairsToRegex converts variadic string paramers to a
+// string to regex map.
+func mapFromPairsToRegex(pairs ...string) (map[string]*regexp.Regexp, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*regexp.Regexp, length/2)
+	for i := 0; i < length; i += 2 {
+		regex, err := regexp.Compile(pairs[i+1])
+		if err != nil {
+			return nil, err
+		}
+		m[pairs[i]] = regex
+	}
+	return m, nil
+}
+
+// matchInArray returns true if the given string value is in the array.
+func matchInArray(arr []string, value string) bool {
+	for _, v := range arr {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// matchMapWithString returns true if the given key/value pairs exist in a given map.
+func matchMapWithString(toCheck map[string]string, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != "" {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v == value {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// matchMapWithRegex returns true if the given key/value pairs exist in a given map compiled against
+// the given regex
+func matchMapWithRegex(toCheck map[string]*regexp.Regexp, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != nil {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v.MatchString(value) {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
diff --git a/vendor/github.com/gorilla/mux/regexp.go b/vendor/github.com/gorilla/mux/regexp.go
new file mode 100644
index 0000000..0189ad3
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/regexp.go
@@ -0,0 +1,323 @@
+// 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
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, matchHost, matchPrefix, matchQuery, strictSlash, useEncodedPath bool) (*routeRegexp, error) {
+	// Check if it is well-formed.
+	idxs, errBraces := braceIndices(tpl)
+	if errBraces != nil {
+		return nil, errBraces
+	}
+	// Backup the original.
+	template := tpl
+	// Now let's parse it.
+	defaultPattern := "[^/]+"
+	if matchQuery {
+		defaultPattern = "[^?&]*"
+	} else if matchHost {
+		defaultPattern = "[^.]+"
+		matchPrefix = false
+	}
+	// Only match strict slash if not matching
+	if matchPrefix || matchHost || matchQuery {
+		strictSlash = false
+	}
+	// Set a flag for strictSlash.
+	endSlash := false
+	if strictSlash && strings.HasSuffix(tpl, "/") {
+		tpl = tpl[:len(tpl)-1]
+		endSlash = true
+	}
+	varsN := make([]string, len(idxs)/2)
+	varsR := make([]*regexp.Regexp, len(idxs)/2)
+	pattern := bytes.NewBufferString("")
+	pattern.WriteByte('^')
+	reverse := bytes.NewBufferString("")
+	var end int
+	var err error
+	for i := 0; i < len(idxs); i += 2 {
+		// Set all values we are interested in.
+		raw := tpl[end:idxs[i]]
+		end = idxs[i+1]
+		parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+		name := parts[0]
+		patt := defaultPattern
+		if len(parts) == 2 {
+			patt = parts[1]
+		}
+		// Name or pattern can't be empty.
+		if name == "" || patt == "" {
+			return nil, fmt.Errorf("mux: missing name or pattern in %q",
+				tpl[idxs[i]:end])
+		}
+		// Build the regexp pattern.
+		fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(i/2), patt)
+
+		// Build the reverse template.
+		fmt.Fprintf(reverse, "%s%%s", raw)
+
+		// Append variable name and compiled pattern.
+		varsN[i/2] = name
+		varsR[i/2], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+		if err != nil {
+			return nil, err
+		}
+	}
+	// Add the remaining.
+	raw := tpl[end:]
+	pattern.WriteString(regexp.QuoteMeta(raw))
+	if strictSlash {
+		pattern.WriteString("[/]?")
+	}
+	if matchQuery {
+		// Add the default pattern if the query value is empty
+		if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+			pattern.WriteString(defaultPattern)
+		}
+	}
+	if !matchPrefix {
+		pattern.WriteByte('$')
+	}
+	reverse.WriteString(raw)
+	if endSlash {
+		reverse.WriteByte('/')
+	}
+	// Compile full regexp.
+	reg, errCompile := regexp.Compile(pattern.String())
+	if errCompile != nil {
+		return nil, errCompile
+	}
+
+	// Check for capturing groups which used to work in older versions
+	if reg.NumSubexp() != len(idxs)/2 {
+		panic(fmt.Sprintf("route %s contains capture groups in its regexp. ", template) +
+			"Only non-capturing groups are accepted: e.g. (?:pattern) instead of (pattern)")
+	}
+
+	// Done!
+	return &routeRegexp{
+		template:       template,
+		matchHost:      matchHost,
+		matchQuery:     matchQuery,
+		strictSlash:    strictSlash,
+		useEncodedPath: useEncodedPath,
+		regexp:         reg,
+		reverse:        reverse.String(),
+		varsN:          varsN,
+		varsR:          varsR,
+	}, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+	// The unmodified template.
+	template string
+	// True for host match, false for path or query string match.
+	matchHost bool
+	// True for query string match, false for path and host match.
+	matchQuery bool
+	// The strictSlash value defined on the route, but disabled if PathPrefix was used.
+	strictSlash bool
+	// Determines whether to use encoded path from getPath function or unencoded
+	// req.URL.Path for path matching
+	useEncodedPath bool
+	// Expanded regexp.
+	regexp *regexp.Regexp
+	// Reverse template.
+	reverse string
+	// Variable names.
+	varsN []string
+	// Variable regexps (validators).
+	varsR []*regexp.Regexp
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+	if !r.matchHost {
+		if r.matchQuery {
+			return r.matchQueryString(req)
+		}
+		path := req.URL.Path
+		if r.useEncodedPath {
+			path = getPath(req)
+		}
+		return r.regexp.MatchString(path)
+	}
+
+	return r.regexp.MatchString(getHost(req))
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+	urlValues := make([]interface{}, len(r.varsN))
+	for k, v := range r.varsN {
+		value, ok := values[v]
+		if !ok {
+			return "", fmt.Errorf("mux: missing route variable %q", v)
+		}
+		urlValues[k] = value
+	}
+	rv := fmt.Sprintf(r.reverse, urlValues...)
+	if !r.regexp.MatchString(rv) {
+		// The URL is checked against the full regexp, instead of checking
+		// individual variables. This is faster but to provide a good error
+		// message, we check individual regexps if the URL doesn't match.
+		for k, v := range r.varsN {
+			if !r.varsR[k].MatchString(values[v]) {
+				return "", fmt.Errorf(
+					"mux: variable %q doesn't match, expected %q", values[v],
+					r.varsR[k].String())
+			}
+		}
+	}
+	return rv, nil
+}
+
+// getURLQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getURLQuery(req *http.Request) string {
+	if !r.matchQuery {
+		return ""
+	}
+	templateKey := strings.SplitN(r.template, "=", 2)[0]
+	for key, vals := range req.URL.Query() {
+		if key == templateKey && len(vals) > 0 {
+			return key + "=" + vals[0]
+		}
+	}
+	return ""
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+	return r.regexp.MatchString(r.getURLQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+	var level, idx int
+	var idxs []int
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '{':
+			if level++; level == 1 {
+				idx = i
+			}
+		case '}':
+			if level--; level == 0 {
+				idxs = append(idxs, idx, i+1)
+			} else if level < 0 {
+				return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+			}
+		}
+	}
+	if level != 0 {
+		return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+	}
+	return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+	return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+	host    *routeRegexp
+	path    *routeRegexp
+	queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v *routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+	// Store host variables.
+	if v.host != nil {
+		host := getHost(req)
+		matches := v.host.regexp.FindStringSubmatchIndex(host)
+		if len(matches) > 0 {
+			extractVars(host, matches, v.host.varsN, m.Vars)
+		}
+	}
+	path := req.URL.Path
+	if r.useEncodedPath {
+		path = getPath(req)
+	}
+	// Store path variables.
+	if v.path != nil {
+		matches := v.path.regexp.FindStringSubmatchIndex(path)
+		if len(matches) > 0 {
+			extractVars(path, matches, v.path.varsN, m.Vars)
+			// Check if we should redirect.
+			if v.path.strictSlash {
+				p1 := strings.HasSuffix(path, "/")
+				p2 := strings.HasSuffix(v.path.template, "/")
+				if p1 != p2 {
+					u, _ := url.Parse(req.URL.String())
+					if p1 {
+						u.Path = u.Path[:len(u.Path)-1]
+					} else {
+						u.Path += "/"
+					}
+					m.Handler = http.RedirectHandler(u.String(), 301)
+				}
+			}
+		}
+	}
+	// Store query string variables.
+	for _, q := range v.queries {
+		queryURL := q.getURLQuery(req)
+		matches := q.regexp.FindStringSubmatchIndex(queryURL)
+		if len(matches) > 0 {
+			extractVars(queryURL, matches, q.varsN, m.Vars)
+		}
+	}
+}
+
+// getHost tries its best to return the request host.
+func getHost(r *http.Request) string {
+	if r.URL.IsAbs() {
+		return r.URL.Host
+	}
+	host := r.Host
+	// Slice off any port information.
+	if i := strings.Index(host, ":"); i != -1 {
+		host = host[:i]
+	}
+	return host
+
+}
+
+func extractVars(input string, matches []int, names []string, output map[string]string) {
+	for i, name := range names {
+		output[name] = input[matches[2*i+2]:matches[2*i+3]]
+	}
+}
diff --git a/vendor/github.com/gorilla/mux/route.go b/vendor/github.com/gorilla/mux/route.go
new file mode 100644
index 0000000..9221915
--- /dev/null
+++ b/vendor/github.com/gorilla/mux/route.go
@@ -0,0 +1,636 @@
+// 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
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// Route stores information to match a request and build URLs.
+type Route struct {
+	// Parent where the route was registered (a Router).
+	parent parentRoute
+	// Request handler for the route.
+	handler http.Handler
+	// List of matchers.
+	matchers []matcher
+	// Manager for the variables from host and path.
+	regexp *routeRegexpGroup
+	// If true, when the path pattern is "/path/", accessing "/path" will
+	// redirect to the former and vice versa.
+	strictSlash bool
+	// If true, when the path pattern is "/path//to", accessing "/path//to"
+	// will not redirect
+	skipClean bool
+	// If true, "/path/foo%2Fbar/to" will match the path "/path/{var}/to"
+	useEncodedPath bool
+	// If true, this route never matches: it is only used to build URLs.
+	buildOnly bool
+	// The name used to build URLs.
+	name string
+	// Error resulted from building a route.
+	err error
+
+	buildVarsFunc BuildVarsFunc
+}
+
+func (r *Route) SkipClean() bool {
+	return r.skipClean
+}
+
+// Match matches the route against the request.
+func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
+	if r.buildOnly || r.err != nil {
+		return false
+	}
+	// Match everything.
+	for _, m := range r.matchers {
+		if matched := m.Match(req, match); !matched {
+			return false
+		}
+	}
+	// Yay, we have a match. Let's collect some info about it.
+	if match.Route == nil {
+		match.Route = r
+	}
+	if match.Handler == nil {
+		match.Handler = r.handler
+	}
+	if match.Vars == nil {
+		match.Vars = make(map[string]string)
+	}
+	// Set variables.
+	if r.regexp != nil {
+		r.regexp.setMatch(req, match, r)
+	}
+	return true
+}
+
+// ----------------------------------------------------------------------------
+// Route attributes
+// ----------------------------------------------------------------------------
+
+// GetError returns an error resulted from building the route, if any.
+func (r *Route) GetError() error {
+	return r.err
+}
+
+// BuildOnly sets the route to never match: it is only used to build URLs.
+func (r *Route) BuildOnly() *Route {
+	r.buildOnly = true
+	return r
+}
+
+// Handler --------------------------------------------------------------------
+
+// Handler sets a handler for the route.
+func (r *Route) Handler(handler http.Handler) *Route {
+	if r.err == nil {
+		r.handler = handler
+	}
+	return r
+}
+
+// HandlerFunc sets a handler function for the route.
+func (r *Route) HandlerFunc(f func(http.ResponseWriter, *http.Request)) *Route {
+	return r.Handler(http.HandlerFunc(f))
+}
+
+// GetHandler returns the handler for the route, if any.
+func (r *Route) GetHandler() http.Handler {
+	return r.handler
+}
+
+// Name -----------------------------------------------------------------------
+
+// Name sets the name for the route, used to build URLs.
+// If the name was registered already it will be overwritten.
+func (r *Route) Name(name string) *Route {
+	if r.name != "" {
+		r.err = fmt.Errorf("mux: route already has name %q, can't set %q",
+			r.name, name)
+	}
+	if r.err == nil {
+		r.name = name
+		r.getNamedRoutes()[name] = r
+	}
+	return r
+}
+
+// GetName returns the name for the route, if any.
+func (r *Route) GetName() string {
+	return r.name
+}
+
+// ----------------------------------------------------------------------------
+// Matchers
+// ----------------------------------------------------------------------------
+
+// matcher types try to match a request.
+type matcher interface {
+	Match(*http.Request, *RouteMatch) bool
+}
+
+// addMatcher adds a matcher to the route.
+func (r *Route) addMatcher(m matcher) *Route {
+	if r.err == nil {
+		r.matchers = append(r.matchers, m)
+	}
+	return r
+}
+
+// addRegexpMatcher adds a host or path matcher and builder to a route.
+func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix, matchQuery bool) error {
+	if r.err != nil {
+		return r.err
+	}
+	r.regexp = r.getRegexpGroup()
+	if !matchHost && !matchQuery {
+		if tpl == "/" && (len(tpl) == 0 || tpl[0] != '/') {
+			return fmt.Errorf("mux: path must start with a slash, got %q", tpl)
+		}
+		if r.regexp.path != nil {
+			tpl = strings.TrimRight(r.regexp.path.template, "/") + tpl
+		}
+	}
+	rr, err := newRouteRegexp(tpl, matchHost, matchPrefix, matchQuery, r.strictSlash, r.useEncodedPath)
+	if err != nil {
+		return err
+	}
+	for _, q := range r.regexp.queries {
+		if err = uniqueVars(rr.varsN, q.varsN); err != nil {
+			return err
+		}
+	}
+	if matchHost {
+		if r.regexp.path != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.path.varsN); err != nil {
+				return err
+			}
+		}
+		r.regexp.host = rr
+	} else {
+		if r.regexp.host != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.host.varsN); err != nil {
+				return err
+			}
+		}
+		if matchQuery {
+			r.regexp.queries = append(r.regexp.queries, rr)
+		} else {
+			r.regexp.path = rr
+		}
+	}
+	r.addMatcher(rr)
+	return nil
+}
+
+// Headers --------------------------------------------------------------------
+
+// headerMatcher matches the request against header values.
+type headerMatcher map[string]string
+
+func (m headerMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithString(m, r.Header, true)
+}
+
+// Headers adds a matcher for request header values.
+// It accepts a sequence of key/value pairs to be matched. For example:
+//
+//     r := mux.NewRouter()
+//     r.Headers("Content-Type", "application/json",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both request header values match.
+// If the value is an empty string, it will match any value if the key is set.
+func (r *Route) Headers(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]string
+		headers, r.err = mapFromPairsToString(pairs...)
+		return r.addMatcher(headerMatcher(headers))
+	}
+	return r
+}
+
+// headerRegexMatcher matches the request against the route given a regex for the header
+type headerRegexMatcher map[string]*regexp.Regexp
+
+func (m headerRegexMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithRegex(m, r.Header, true)
+}
+
+// HeadersRegexp accepts a sequence of key/value pairs, where the value has regex
+// support. For example:
+//
+//     r := mux.NewRouter()
+//     r.HeadersRegexp("Content-Type", "application/(text|json)",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both the request header matches both regular expressions.
+// It the value is an empty string, it will match any value if the key is set.
+func (r *Route) HeadersRegexp(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]*regexp.Regexp
+		headers, r.err = mapFromPairsToRegex(pairs...)
+		return r.addMatcher(headerRegexMatcher(headers))
+	}
+	return r
+}
+
+// Host -----------------------------------------------------------------------
+
+// Host adds a matcher for the URL host.
+// It accepts a template with zero or more URL variables enclosed by {}.
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next dot.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Host("www.example.com")
+//     r.Host("{subdomain}.domain.com")
+//     r.Host("{subdomain:[a-z]+}.domain.com")
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Host(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, true, false, false)
+	return r
+}
+
+// MatcherFunc ----------------------------------------------------------------
+
+// MatcherFunc is the function signature used by custom matchers.
+type MatcherFunc func(*http.Request, *RouteMatch) bool
+
+// Match returns the match for a given request.
+func (m MatcherFunc) Match(r *http.Request, match *RouteMatch) bool {
+	return m(r, match)
+}
+
+// MatcherFunc adds a custom function to be used as request matcher.
+func (r *Route) MatcherFunc(f MatcherFunc) *Route {
+	return r.addMatcher(f)
+}
+
+// Methods --------------------------------------------------------------------
+
+// methodMatcher matches the request against HTTP methods.
+type methodMatcher []string
+
+func (m methodMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.Method)
+}
+
+// Methods adds a matcher for HTTP methods.
+// It accepts a sequence of one or more methods to be matched, e.g.:
+// "GET", "POST", "PUT".
+func (r *Route) Methods(methods ...string) *Route {
+	for k, v := range methods {
+		methods[k] = strings.ToUpper(v)
+	}
+	return r.addMatcher(methodMatcher(methods))
+}
+
+// Path -----------------------------------------------------------------------
+
+// Path adds a matcher for the URL path.
+// It accepts a template with zero or more URL variables enclosed by {}. The
+// template must start with a "/".
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Path("/products/").Handler(ProductsHandler)
+//     r.Path("/products/{key}").Handler(ProductsHandler)
+//     r.Path("/articles/{category}/{id:[0-9]+}").
+//       Handler(ArticleHandler)
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Path(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, false, false)
+	return r
+}
+
+// PathPrefix -----------------------------------------------------------------
+
+// PathPrefix adds a matcher for the URL path prefix. This matches if the given
+// template is a prefix of the full URL path. See Route.Path() for details on
+// the tpl argument.
+//
+// Note that it does not treat slashes specially ("/foobar/" will be matched by
+// the prefix "/foo") so you may want to use a trailing slash here.
+//
+// Also note that the setting of Router.StrictSlash() has no effect on routes
+// with a PathPrefix matcher.
+func (r *Route) PathPrefix(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, true, false)
+	return r
+}
+
+// Query ----------------------------------------------------------------------
+
+// Queries adds a matcher for URL query values.
+// It accepts a sequence of key/value pairs. Values may define variables.
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Queries("foo", "bar", "id", "{id:[0-9]+}")
+//
+// The above route will only match if the URL contains the defined queries
+// values, e.g.: ?foo=bar&id=42.
+//
+// It the value is an empty string, it will match any value if the key is set.
+//
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+func (r *Route) Queries(pairs ...string) *Route {
+	length := len(pairs)
+	if length%2 != 0 {
+		r.err = fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+		return nil
+	}
+	for i := 0; i < length; i += 2 {
+		if r.err = r.addRegexpMatcher(pairs[i]+"="+pairs[i+1], false, false, true); r.err != nil {
+			return r
+		}
+	}
+
+	return r
+}
+
+// Schemes --------------------------------------------------------------------
+
+// schemeMatcher matches the request against URL schemes.
+type schemeMatcher []string
+
+func (m schemeMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.URL.Scheme)
+}
+
+// Schemes adds a matcher for URL schemes.
+// It accepts a sequence of schemes to be matched, e.g.: "http", "https".
+func (r *Route) Schemes(schemes ...string) *Route {
+	for k, v := range schemes {
+		schemes[k] = strings.ToLower(v)
+	}
+	return r.addMatcher(schemeMatcher(schemes))
+}
+
+// BuildVarsFunc --------------------------------------------------------------
+
+// BuildVarsFunc is the function signature used by custom build variable
+// functions (which can modify route variables before a route's URL is built).
+type BuildVarsFunc func(map[string]string) map[string]string
+
+// BuildVarsFunc adds a custom function to be used to modify build variables
+// before a route's URL is built.
+func (r *Route) BuildVarsFunc(f BuildVarsFunc) *Route {
+	r.buildVarsFunc = f
+	return r
+}
+
+// Subrouter ------------------------------------------------------------------
+
+// Subrouter creates a subrouter for the route.
+//
+// It will test the inner routes only if the parent route matched. For example:
+//
+//     r := mux.NewRouter()
+//     s := r.Host("www.example.com").Subrouter()
+//     s.HandleFunc("/products/", ProductsHandler)
+//     s.HandleFunc("/products/{key}", ProductHandler)
+//     s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+//
+// Here, the routes registered in the subrouter won't be tested if the host
+// doesn't match.
+func (r *Route) Subrouter() *Router {
+	router := &Router{parent: r, strictSlash: r.strictSlash}
+	r.addMatcher(router)
+	return router
+}
+
+// ----------------------------------------------------------------------------
+// URL building
+// ----------------------------------------------------------------------------
+
+// URL builds a URL for the route.
+//
+// It accepts a sequence of key/value pairs for the route variables. For
+// example, given this route:
+//
+//     r := mux.NewRouter()
+//     r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//       Name("article")
+//
+// ...a URL for it can be built using:
+//
+//     url, err := r.Get("article").URL("category", "technology", "id", "42")
+//
+// ...which will return an url.URL with the following path:
+//
+//     "/articles/technology/42"
+//
+// This also works for host variables:
+//
+//     r := mux.NewRouter()
+//     r.Host("{subdomain}.domain.com").
+//       HandleFunc("/articles/{category}/{id:[0-9]+}", 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.
+func (r *Route) URL(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil {
+		return nil, errors.New("mux: route doesn't have a host or path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	var scheme, host, path string
+	if r.regexp.host != nil {
+		// Set a default scheme.
+		scheme = "http"
+		if host, err = r.regexp.host.url(values); err != nil {
+			return nil, err
+		}
+	}
+	if r.regexp.path != nil {
+		if path, err = r.regexp.path.url(values); err != nil {
+			return nil, err
+		}
+	}
+	return &url.URL{
+		Scheme: scheme,
+		Host:   host,
+		Path:   path,
+	}, nil
+}
+
+// URLHost builds the host part of the URL for a route. See Route.URL().
+//
+// The route must have a host defined.
+func (r *Route) URLHost(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.host == nil {
+		return nil, errors.New("mux: route doesn't have a host")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	host, err := r.regexp.host.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Scheme: "http",
+		Host:   host,
+	}, nil
+}
+
+// URLPath builds the path part of the URL for a route. See Route.URL().
+//
+// The route must have a path defined.
+func (r *Route) URLPath(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.path == nil {
+		return nil, errors.New("mux: route doesn't have a path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	path, err := r.regexp.path.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Path: path,
+	}, nil
+}
+
+// GetPathTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a path.
+func (r *Route) GetPathTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp == nil || r.regexp.path == nil {
+		return "", errors.New("mux: route doesn't have a path")
+	}
+	return r.regexp.path.template, nil
+}
+
+// GetHostTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a host.
+func (r *Route) GetHostTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp == nil || r.regexp.host == nil {
+		return "", errors.New("mux: route doesn't have a host")
+	}
+	return r.regexp.host.template, nil
+}
+
+// prepareVars converts the route variable pairs into a map. If the route has a
+// BuildVarsFunc, it is invoked.
+func (r *Route) prepareVars(pairs ...string) (map[string]string, error) {
+	m, err := mapFromPairsToString(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	return r.buildVars(m), nil
+}
+
+func (r *Route) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	if r.buildVarsFunc != nil {
+		m = r.buildVarsFunc(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// parentRoute allows routes to know about parent host and path definitions.
+type parentRoute interface {
+	getNamedRoutes() map[string]*Route
+	getRegexpGroup() *routeRegexpGroup
+	buildVars(map[string]string) map[string]string
+}
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Route) getNamedRoutes() map[string]*Route {
+	if r.parent == nil {
+		// During tests router is not always set.
+		r.parent = NewRouter()
+	}
+	return r.parent.getNamedRoutes()
+}
+
+// getRegexpGroup returns regexp definitions from this route.
+func (r *Route) getRegexpGroup() *routeRegexpGroup {
+	if r.regexp == nil {
+		if r.parent == nil {
+			// During tests router is not always set.
+			r.parent = NewRouter()
+		}
+		regexp := r.parent.getRegexpGroup()
+		if regexp == nil {
+			r.regexp = new(routeRegexpGroup)
+		} else {
+			// Copy.
+			r.regexp = &routeRegexpGroup{
+				host:    regexp.host,
+				path:    regexp.path,
+				queries: regexp.queries,
+			}
+		}
+	}
+	return r.regexp
+}