9feec51e2d
This commit introduces a network simulation framework which can be used to run simulated networks of devp2p nodes. The intention is to use this for testing protocols, performing benchmarks and visualising emergent network behaviour.
412 lines
13 KiB
Go
412 lines
13 KiB
Go
// Copyright 2013 Julien Schmidt. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be found
|
|
// in the LICENSE file.
|
|
|
|
// Package httprouter is a trie based high performance HTTP request router.
|
|
//
|
|
// A trivial example is:
|
|
//
|
|
// package main
|
|
//
|
|
// import (
|
|
// "fmt"
|
|
// "github.com/julienschmidt/httprouter"
|
|
// "net/http"
|
|
// "log"
|
|
// )
|
|
//
|
|
// func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
|
|
// fmt.Fprint(w, "Welcome!\n")
|
|
// }
|
|
//
|
|
// func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
|
|
// fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
|
|
// }
|
|
//
|
|
// func main() {
|
|
// router := httprouter.New()
|
|
// router.GET("/", Index)
|
|
// router.GET("/hello/:name", Hello)
|
|
//
|
|
// log.Fatal(http.ListenAndServe(":8080", router))
|
|
// }
|
|
//
|
|
// The router matches incoming requests by the request method and the path.
|
|
// If a handle is registered for this path and method, the router delegates the
|
|
// request to that function.
|
|
// For the methods GET, POST, PUT, PATCH and DELETE shortcut functions exist to
|
|
// register handles, for all other methods router.Handle can be used.
|
|
//
|
|
// The registered path, against which the router matches incoming requests, can
|
|
// contain two types of parameters:
|
|
// Syntax Type
|
|
// :name named parameter
|
|
// *name catch-all parameter
|
|
//
|
|
// Named parameters are dynamic path segments. They match anything until the
|
|
// next '/' or the path end:
|
|
// Path: /blog/:category/:post
|
|
//
|
|
// Requests:
|
|
// /blog/go/request-routers match: category="go", post="request-routers"
|
|
// /blog/go/request-routers/ no match, but the router would redirect
|
|
// /blog/go/ no match
|
|
// /blog/go/request-routers/comments no match
|
|
//
|
|
// Catch-all parameters match anything until the path end, including the
|
|
// directory index (the '/' before the catch-all). Since they match anything
|
|
// until the end, catch-all parameters must always be the final path element.
|
|
// Path: /files/*filepath
|
|
//
|
|
// Requests:
|
|
// /files/ match: filepath="/"
|
|
// /files/LICENSE match: filepath="/LICENSE"
|
|
// /files/templates/article.html match: filepath="/templates/article.html"
|
|
// /files no match, but the router would redirect
|
|
//
|
|
// The value of parameters is saved as a slice of the Param struct, consisting
|
|
// each of a key and a value. The slice is passed to the Handle func as a third
|
|
// parameter.
|
|
// There are two ways to retrieve the value of a parameter:
|
|
// // by the name of the parameter
|
|
// user := ps.ByName("user") // defined by :user or *user
|
|
//
|
|
// // by the index of the parameter. This way you can also get the name (key)
|
|
// thirdKey := ps[2].Key // the name of the 3rd parameter
|
|
// thirdValue := ps[2].Value // the value of the 3rd parameter
|
|
package httprouter
|
|
|
|
import (
|
|
"net/http"
|
|
)
|
|
|
|
// Handle is a function that can be registered to a route to handle HTTP
|
|
// requests. Like http.HandlerFunc, but has a third parameter for the values of
|
|
// wildcards (variables).
|
|
type Handle func(http.ResponseWriter, *http.Request, Params)
|
|
|
|
// Param is a single URL parameter, consisting of a key and a value.
|
|
type Param struct {
|
|
Key string
|
|
Value string
|
|
}
|
|
|
|
// Params is a Param-slice, as returned by the router.
|
|
// The slice is ordered, the first URL parameter is also the first slice value.
|
|
// It is therefore safe to read values by the index.
|
|
type Params []Param
|
|
|
|
// ByName returns the value of the first Param which key matches the given name.
|
|
// If no matching Param is found, an empty string is returned.
|
|
func (ps Params) ByName(name string) string {
|
|
for i := range ps {
|
|
if ps[i].Key == name {
|
|
return ps[i].Value
|
|
}
|
|
}
|
|
return ""
|
|
}
|
|
|
|
// Router is a http.Handler which can be used to dispatch requests to different
|
|
// handler functions via configurable routes
|
|
type Router struct {
|
|
trees map[string]*node
|
|
|
|
// Enables automatic redirection if the current route can't be matched but a
|
|
// handler for the path with (without) the trailing slash exists.
|
|
// For example if /foo/ is requested but a route only exists for /foo, the
|
|
// client is redirected to /foo with http status code 301 for GET requests
|
|
// and 307 for all other request methods.
|
|
RedirectTrailingSlash bool
|
|
|
|
// If enabled, the router tries to fix the current request path, if no
|
|
// handle is registered for it.
|
|
// First superfluous path elements like ../ or // are removed.
|
|
// Afterwards the router does a case-insensitive lookup of the cleaned path.
|
|
// If a handle can be found for this route, the router makes a redirection
|
|
// to the corrected path with status code 301 for GET requests and 307 for
|
|
// all other request methods.
|
|
// For example /FOO and /..//Foo could be redirected to /foo.
|
|
// RedirectTrailingSlash is independent of this option.
|
|
RedirectFixedPath bool
|
|
|
|
// If enabled, the router checks if another method is allowed for the
|
|
// current route, if the current request can not be routed.
|
|
// If this is the case, the request is answered with 'Method Not Allowed'
|
|
// and HTTP status code 405.
|
|
// If no other Method is allowed, the request is delegated to the NotFound
|
|
// handler.
|
|
HandleMethodNotAllowed bool
|
|
|
|
// If enabled, the router automatically replies to OPTIONS requests.
|
|
// Custom OPTIONS handlers take priority over automatic replies.
|
|
HandleOPTIONS bool
|
|
|
|
// Configurable http.Handler which is called when no matching route is
|
|
// found. If it is not set, http.NotFound is used.
|
|
NotFound http.Handler
|
|
|
|
// Configurable http.Handler which is called when a request
|
|
// cannot be routed and HandleMethodNotAllowed is true.
|
|
// If it is not set, http.Error with http.StatusMethodNotAllowed is used.
|
|
// The "Allow" header with allowed request methods is set before the handler
|
|
// is called.
|
|
MethodNotAllowed http.Handler
|
|
|
|
// Function to handle panics recovered from http handlers.
|
|
// It should be used to generate a error page and return the http error code
|
|
// 500 (Internal Server Error).
|
|
// The handler can be used to keep your server from crashing because of
|
|
// unrecovered panics.
|
|
PanicHandler func(http.ResponseWriter, *http.Request, interface{})
|
|
}
|
|
|
|
// Make sure the Router conforms with the http.Handler interface
|
|
var _ http.Handler = New()
|
|
|
|
// New returns a new initialized Router.
|
|
// Path auto-correction, including trailing slashes, is enabled by default.
|
|
func New() *Router {
|
|
return &Router{
|
|
RedirectTrailingSlash: true,
|
|
RedirectFixedPath: true,
|
|
HandleMethodNotAllowed: true,
|
|
HandleOPTIONS: true,
|
|
}
|
|
}
|
|
|
|
// GET is a shortcut for router.Handle("GET", path, handle)
|
|
func (r *Router) GET(path string, handle Handle) {
|
|
r.Handle("GET", path, handle)
|
|
}
|
|
|
|
// HEAD is a shortcut for router.Handle("HEAD", path, handle)
|
|
func (r *Router) HEAD(path string, handle Handle) {
|
|
r.Handle("HEAD", path, handle)
|
|
}
|
|
|
|
// OPTIONS is a shortcut for router.Handle("OPTIONS", path, handle)
|
|
func (r *Router) OPTIONS(path string, handle Handle) {
|
|
r.Handle("OPTIONS", path, handle)
|
|
}
|
|
|
|
// POST is a shortcut for router.Handle("POST", path, handle)
|
|
func (r *Router) POST(path string, handle Handle) {
|
|
r.Handle("POST", path, handle)
|
|
}
|
|
|
|
// PUT is a shortcut for router.Handle("PUT", path, handle)
|
|
func (r *Router) PUT(path string, handle Handle) {
|
|
r.Handle("PUT", path, handle)
|
|
}
|
|
|
|
// PATCH is a shortcut for router.Handle("PATCH", path, handle)
|
|
func (r *Router) PATCH(path string, handle Handle) {
|
|
r.Handle("PATCH", path, handle)
|
|
}
|
|
|
|
// DELETE is a shortcut for router.Handle("DELETE", path, handle)
|
|
func (r *Router) DELETE(path string, handle Handle) {
|
|
r.Handle("DELETE", path, handle)
|
|
}
|
|
|
|
// Handle registers a new request handle with the given path and method.
|
|
//
|
|
// For GET, POST, PUT, PATCH and DELETE requests the respective shortcut
|
|
// functions can be used.
|
|
//
|
|
// This function is intended for bulk loading and to allow the usage of less
|
|
// frequently used, non-standardized or custom methods (e.g. for internal
|
|
// communication with a proxy).
|
|
func (r *Router) Handle(method, path string, handle Handle) {
|
|
if path[0] != '/' {
|
|
panic("path must begin with '/' in path '" + path + "'")
|
|
}
|
|
|
|
if r.trees == nil {
|
|
r.trees = make(map[string]*node)
|
|
}
|
|
|
|
root := r.trees[method]
|
|
if root == nil {
|
|
root = new(node)
|
|
r.trees[method] = root
|
|
}
|
|
|
|
root.addRoute(path, handle)
|
|
}
|
|
|
|
// Handler is an adapter which allows the usage of an http.Handler as a
|
|
// request handle.
|
|
func (r *Router) Handler(method, path string, handler http.Handler) {
|
|
r.Handle(method, path,
|
|
func(w http.ResponseWriter, req *http.Request, _ Params) {
|
|
handler.ServeHTTP(w, req)
|
|
},
|
|
)
|
|
}
|
|
|
|
// HandlerFunc is an adapter which allows the usage of an http.HandlerFunc as a
|
|
// request handle.
|
|
func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc) {
|
|
r.Handler(method, path, handler)
|
|
}
|
|
|
|
// ServeFiles serves files from the given file system root.
|
|
// The path must end with "/*filepath", files are then served from the local
|
|
// path /defined/root/dir/*filepath.
|
|
// For example if root is "/etc" and *filepath is "passwd", the local file
|
|
// "/etc/passwd" would be served.
|
|
// Internally a http.FileServer is used, therefore http.NotFound is used instead
|
|
// of the Router's NotFound handler.
|
|
// To use the operating system's file system implementation,
|
|
// use http.Dir:
|
|
// router.ServeFiles("/src/*filepath", http.Dir("/var/www"))
|
|
func (r *Router) ServeFiles(path string, root http.FileSystem) {
|
|
if len(path) < 10 || path[len(path)-10:] != "/*filepath" {
|
|
panic("path must end with /*filepath in path '" + path + "'")
|
|
}
|
|
|
|
fileServer := http.FileServer(root)
|
|
|
|
r.GET(path, func(w http.ResponseWriter, req *http.Request, ps Params) {
|
|
req.URL.Path = ps.ByName("filepath")
|
|
fileServer.ServeHTTP(w, req)
|
|
})
|
|
}
|
|
|
|
func (r *Router) recv(w http.ResponseWriter, req *http.Request) {
|
|
if rcv := recover(); rcv != nil {
|
|
r.PanicHandler(w, req, rcv)
|
|
}
|
|
}
|
|
|
|
// Lookup allows the manual lookup of a method + path combo.
|
|
// This is e.g. useful to build a framework around this router.
|
|
// If the path was found, it returns the handle function and the path parameter
|
|
// values. Otherwise the third return value indicates whether a redirection to
|
|
// the same path with an extra / without the trailing slash should be performed.
|
|
func (r *Router) Lookup(method, path string) (Handle, Params, bool) {
|
|
if root := r.trees[method]; root != nil {
|
|
return root.getValue(path)
|
|
}
|
|
return nil, nil, false
|
|
}
|
|
|
|
func (r *Router) allowed(path, reqMethod string) (allow string) {
|
|
if path == "*" { // server-wide
|
|
for method := range r.trees {
|
|
if method == "OPTIONS" {
|
|
continue
|
|
}
|
|
|
|
// add request method to list of allowed methods
|
|
if len(allow) == 0 {
|
|
allow = method
|
|
} else {
|
|
allow += ", " + method
|
|
}
|
|
}
|
|
} else { // specific path
|
|
for method := range r.trees {
|
|
// Skip the requested method - we already tried this one
|
|
if method == reqMethod || method == "OPTIONS" {
|
|
continue
|
|
}
|
|
|
|
handle, _, _ := r.trees[method].getValue(path)
|
|
if handle != nil {
|
|
// add request method to list of allowed methods
|
|
if len(allow) == 0 {
|
|
allow = method
|
|
} else {
|
|
allow += ", " + method
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if len(allow) > 0 {
|
|
allow += ", OPTIONS"
|
|
}
|
|
return
|
|
}
|
|
|
|
// ServeHTTP makes the router implement the http.Handler interface.
|
|
func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
|
|
if r.PanicHandler != nil {
|
|
defer r.recv(w, req)
|
|
}
|
|
|
|
path := req.URL.Path
|
|
|
|
if root := r.trees[req.Method]; root != nil {
|
|
if handle, ps, tsr := root.getValue(path); handle != nil {
|
|
handle(w, req, ps)
|
|
return
|
|
} else if req.Method != "CONNECT" && path != "/" {
|
|
code := 301 // Permanent redirect, request with GET method
|
|
if req.Method != "GET" {
|
|
// Temporary redirect, request with same method
|
|
// As of Go 1.3, Go does not support status code 308.
|
|
code = 307
|
|
}
|
|
|
|
if tsr && r.RedirectTrailingSlash {
|
|
if len(path) > 1 && path[len(path)-1] == '/' {
|
|
req.URL.Path = path[:len(path)-1]
|
|
} else {
|
|
req.URL.Path = path + "/"
|
|
}
|
|
http.Redirect(w, req, req.URL.String(), code)
|
|
return
|
|
}
|
|
|
|
// Try to fix the request path
|
|
if r.RedirectFixedPath {
|
|
fixedPath, found := root.findCaseInsensitivePath(
|
|
CleanPath(path),
|
|
r.RedirectTrailingSlash,
|
|
)
|
|
if found {
|
|
req.URL.Path = string(fixedPath)
|
|
http.Redirect(w, req, req.URL.String(), code)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if req.Method == "OPTIONS" {
|
|
// Handle OPTIONS requests
|
|
if r.HandleOPTIONS {
|
|
if allow := r.allowed(path, req.Method); len(allow) > 0 {
|
|
w.Header().Set("Allow", allow)
|
|
return
|
|
}
|
|
}
|
|
} else {
|
|
// Handle 405
|
|
if r.HandleMethodNotAllowed {
|
|
if allow := r.allowed(path, req.Method); len(allow) > 0 {
|
|
w.Header().Set("Allow", allow)
|
|
if r.MethodNotAllowed != nil {
|
|
r.MethodNotAllowed.ServeHTTP(w, req)
|
|
} else {
|
|
http.Error(w,
|
|
http.StatusText(http.StatusMethodNotAllowed),
|
|
http.StatusMethodNotAllowed,
|
|
)
|
|
}
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
// Handle 404
|
|
if r.NotFound != nil {
|
|
r.NotFound.ServeHTTP(w, req)
|
|
} else {
|
|
http.NotFound(w, req)
|
|
}
|
|
}
|