From a7bae3b2a645653a149b9bcbb9bdc857e27027e2 Mon Sep 17 00:00:00 2001 From: Bas van Kervel Date: Wed, 24 Feb 2016 11:19:00 +0100 Subject: [PATCH] rpc/http: improve request handling --- Godeps/Godeps.json | 4 + .../src/github.com/rs/cors/.travis.yml | 4 + .../_workspace/src/github.com/rs/cors/LICENSE | 19 ++ .../src/github.com/rs/cors/README.md | 84 +++++ .../_workspace/src/github.com/rs/cors/cors.go | 308 ++++++++++++++++++ .../src/github.com/rs/cors/utils.go | 27 ++ .../src/github.com/rs/xhandler/.travis.yml | 7 + .../src/github.com/rs/xhandler/LICENSE | 19 ++ .../src/github.com/rs/xhandler/README.md | 134 ++++++++ .../src/github.com/rs/xhandler/chain.go | 93 ++++++ .../src/github.com/rs/xhandler/middleware.go | 59 ++++ .../src/github.com/rs/xhandler/xhandler.go | 42 +++ cmd/utils/flags.go | 2 +- rpc/http.go | 277 ++++------------ rpc/server.go | 60 +++- 15 files changed, 903 insertions(+), 236 deletions(-) create mode 100644 Godeps/_workspace/src/github.com/rs/cors/.travis.yml create mode 100644 Godeps/_workspace/src/github.com/rs/cors/LICENSE create mode 100644 Godeps/_workspace/src/github.com/rs/cors/README.md create mode 100644 Godeps/_workspace/src/github.com/rs/cors/cors.go create mode 100644 Godeps/_workspace/src/github.com/rs/cors/utils.go create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/.travis.yml create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/LICENSE create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/README.md create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/chain.go create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/middleware.go create mode 100644 Godeps/_workspace/src/github.com/rs/xhandler/xhandler.go diff --git a/Godeps/Godeps.json b/Godeps/Godeps.json index 9bcc8c756..e02f15882 100644 --- a/Godeps/Godeps.json +++ b/Godeps/Godeps.json @@ -138,6 +138,10 @@ "ImportPath": "github.com/robertkrimen/otto/token", "Rev": "53221230c215611a90762720c9042ac782ef74ee" }, + { + "ImportPath": "github.com/rs/cors", + "Rev": "5950cf11d77f8a61b432a25dd4d444b4ced01379" + }, { "ImportPath": "github.com/syndtr/goleveldb/leveldb", "Rev": "ad0d8b2ab58a55ed5c58073aa46451d5e1ca1280" diff --git a/Godeps/_workspace/src/github.com/rs/cors/.travis.yml b/Godeps/_workspace/src/github.com/rs/cors/.travis.yml new file mode 100644 index 000000000..bbb5185a2 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/cors/.travis.yml @@ -0,0 +1,4 @@ +language: go +go: +- 1.3 +- 1.4 diff --git a/Godeps/_workspace/src/github.com/rs/cors/LICENSE b/Godeps/_workspace/src/github.com/rs/cors/LICENSE new file mode 100644 index 000000000..d8e2df5a4 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/cors/LICENSE @@ -0,0 +1,19 @@ +Copyright (c) 2014 Olivier Poitrey + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is furnished +to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. diff --git a/Godeps/_workspace/src/github.com/rs/cors/README.md b/Godeps/_workspace/src/github.com/rs/cors/README.md new file mode 100644 index 000000000..6f70c30ac --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/cors/README.md @@ -0,0 +1,84 @@ +# Go CORS handler [![godoc](http://img.shields.io/badge/godoc-reference-blue.svg?style=flat)](https://godoc.org/github.com/rs/cors) [![license](http://img.shields.io/badge/license-MIT-red.svg?style=flat)](https://raw.githubusercontent.com/rs/cors/master/LICENSE) [![build](https://img.shields.io/travis/rs/cors.svg?style=flat)](https://travis-ci.org/rs/cors) + +CORS is a `net/http` handler implementing [Cross Origin Resource Sharing W3 specification](http://www.w3.org/TR/cors/) in Golang. + +## Getting Started + +After installing Go and setting up your [GOPATH](http://golang.org/doc/code.html#GOPATH), create your first `.go` file. We'll call it `server.go`. + +```go +package main + +import ( + "net/http" + + "github.com/rs/cors" +) + +func main() { + h := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + w.Header().Set("Content-Type", "application/json") + w.Write([]byte("{\"hello\": \"world\"}")) + }) + + // cors.Default() setup the middleware with default options being + // all origins accepted with simple methods (GET, POST). See + // documentation below for more options. + handler = cors.Default().Handler(h) + http.ListenAndServe(":8080", handler) +} +``` + +Install `cors`: + + go get github.com/rs/cors + +Then run your server: + + go run server.go + +The server now runs on `localhost:8080`: + + $ curl -D - -H 'Origin: http://foo.com' http://localhost:8080/ + HTTP/1.1 200 OK + Access-Control-Allow-Origin: foo.com + Content-Type: application/json + Date: Sat, 25 Oct 2014 03:43:57 GMT + Content-Length: 18 + + {"hello": "world"} + +### More Examples + +* `net/http`: [examples/nethttp/server.go](https://github.com/rs/cors/blob/master/examples/nethttp/server.go) +* [Goji](https://goji.io): [examples/goji/server.go](https://github.com/rs/cors/blob/master/examples/goji/server.go) +* [Martini](http://martini.codegangsta.io): [examples/martini/server.go](https://github.com/rs/cors/blob/master/examples/martini/server.go) +* [Negroni](https://github.com/codegangsta/negroni): [examples/negroni/server.go](https://github.com/rs/cors/blob/master/examples/negroni/server.go) +* [Alice](https://github.com/justinas/alice): [examples/alice/server.go](https://github.com/rs/cors/blob/master/examples/alice/server.go) + +## Parameters + +Parameters are passed to the middleware thru the `cors.New` method as follow: + +```go +c := cors.New(cors.Options{ + AllowedOrigins: []string{"http://foo.com"}, + AllowCredentials: true, +}) + +// Insert the middleware +handler = c.Handler(handler) +``` + +* **AllowedOrigins** `[]string`: A list of origins a cross-domain request can be executed from. If the special `*` value is present in the list, all origins will be allowed. The default value is `*`. +* **AllowedMethods** `[]string`: A list of methods the client is allowed to use with cross-domain requests. +* **AllowedHeaders** `[]string`: A list of non simple headers the client is allowed to use with cross-domain requests. Default value is simple methods (`GET` and `POST`) +* **ExposedHeaders** `[]string`: Indicates which headers are safe to expose to the API of a CORS API specification +* **AllowCredentials** `bool`: Indicates whether the request can include user credentials like cookies, HTTP authentication or client side SSL certificates. The default is `false`. +* **MaxAge** `int`: Indicates how long (in seconds) the results of a preflight request can be cached. The default is `0` which stands for no max age. + +See [API documentation](http://godoc.org/github.com/rs/cors) for more info. + +## Licenses + +All source code is licensed under the [MIT License](https://raw.github.com/rs/cors/master/LICENSE). diff --git a/Godeps/_workspace/src/github.com/rs/cors/cors.go b/Godeps/_workspace/src/github.com/rs/cors/cors.go new file mode 100644 index 000000000..276bc40bb --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/cors/cors.go @@ -0,0 +1,308 @@ +/* +Package cors is net/http handler to handle CORS related requests +as defined by http://www.w3.org/TR/cors/ + +You can configure it by passing an option struct to cors.New: + + c := cors.New(cors.Options{ + AllowedOrigins: []string{"foo.com"}, + AllowedMethods: []string{"GET", "POST", "DELETE"}, + AllowCredentials: true, + }) + +Then insert the handler in the chain: + + handler = c.Handler(handler) + +See Options documentation for more options. + +The resulting handler is a standard net/http handler. +*/ +package cors + +import ( + "log" + "net/http" + "os" + "strconv" + "strings" +) + +// Options is a configuration container to setup the CORS middleware. +type Options struct { + // AllowedOrigins is a list of origins a cross-domain request can be executed from. + // If the special "*" value is present in the list, all origins will be allowed. + // Default value is ["*"] + AllowedOrigins []string + // AllowedMethods is a list of methods the client is allowed to use with + // cross-domain requests. Default value is simple methods (GET and POST) + AllowedMethods []string + // AllowedHeaders is list of non simple headers the client is allowed to use with + // cross-domain requests. + // If the special "*" value is present in the list, all headers will be allowed. + // Default value is [] but "Origin" is always appended to the list. + AllowedHeaders []string + // ExposedHeaders indicates which headers are safe to expose to the API of a CORS + // API specification + ExposedHeaders []string + // AllowCredentials indicates whether the request can include user credentials like + // cookies, HTTP authentication or client side SSL certificates. + AllowCredentials bool + // MaxAge indicates how long (in seconds) the results of a preflight request + // can be cached + MaxAge int + // Debugging flag adds additional output to debug server side CORS issues + Debug bool + // log object to use when debugging + log *log.Logger +} + +type Cors struct { + // The CORS Options + options Options +} + +// New creates a new Cors handler with the provided options. +func New(options Options) *Cors { + // Normalize options + // Note: for origins and methods matching, the spec requires a case-sensitive matching. + // As it may error prone, we chose to ignore the spec here. + normOptions := Options{ + AllowedOrigins: convert(options.AllowedOrigins, strings.ToLower), + AllowedMethods: convert(options.AllowedMethods, strings.ToUpper), + // Origin is always appended as some browsers will always request + // for this header at preflight + AllowedHeaders: convert(append(options.AllowedHeaders, "Origin"), http.CanonicalHeaderKey), + ExposedHeaders: convert(options.ExposedHeaders, http.CanonicalHeaderKey), + AllowCredentials: options.AllowCredentials, + MaxAge: options.MaxAge, + Debug: options.Debug, + log: log.New(os.Stdout, "[cors] ", log.LstdFlags), + } + if len(normOptions.AllowedOrigins) == 0 { + // Default is all origins + normOptions.AllowedOrigins = []string{"*"} + } + if len(normOptions.AllowedHeaders) == 1 { + // Add some sensible defaults + normOptions.AllowedHeaders = []string{"Origin", "Accept", "Content-Type"} + } + if len(normOptions.AllowedMethods) == 0 { + // Default is simple methods + normOptions.AllowedMethods = []string{"GET", "POST"} + } + + if normOptions.Debug { + normOptions.log.Printf("Options: %v", normOptions) + } + return &Cors{ + options: normOptions, + } +} + +// Default creates a new Cors handler with default options +func Default() *Cors { + return New(Options{}) +} + +// Handler apply the CORS specification on the request, and add relevant CORS headers +// as necessary. +func (cors *Cors) Handler(h http.Handler) http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + if r.Method == "OPTIONS" { + cors.logf("Handler: Preflight request") + cors.handlePreflight(w, r) + // Preflight requests are standalone and should stop the chain as some other + // middleware may not handle OPTIONS requests correctly. One typical example + // is authentication middleware ; OPTIONS requests won't carry authentication + // headers (see #1) + } else { + cors.logf("Handler: Actual request") + cors.handleActualRequest(w, r) + h.ServeHTTP(w, r) + } + }) +} + +// Martini compatible handler +func (cors *Cors) HandlerFunc(w http.ResponseWriter, r *http.Request) { + if r.Method == "OPTIONS" { + cors.logf("HandlerFunc: Preflight request") + cors.handlePreflight(w, r) + } else { + cors.logf("HandlerFunc: Actual request") + cors.handleActualRequest(w, r) + } +} + +// Negroni compatible interface +func (cors *Cors) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) { + if r.Method == "OPTIONS" { + cors.logf("ServeHTTP: Preflight request") + cors.handlePreflight(w, r) + // Preflight requests are standalone and should stop the chain as some other + // middleware may not handle OPTIONS requests correctly. One typical example + // is authentication middleware ; OPTIONS requests won't carry authentication + // headers (see #1) + } else { + cors.logf("ServeHTTP: Actual request") + cors.handleActualRequest(w, r) + next(w, r) + } +} + +// handlePreflight handles pre-flight CORS requests +func (cors *Cors) handlePreflight(w http.ResponseWriter, r *http.Request) { + options := cors.options + headers := w.Header() + origin := r.Header.Get("Origin") + + if r.Method != "OPTIONS" { + cors.logf(" Preflight aborted: %s!=OPTIONS", r.Method) + return + } + if origin == "" { + cors.logf(" Preflight aborted: empty origin") + return + } + if !cors.isOriginAllowed(origin) { + cors.logf(" Preflight aborted: origin '%s' not allowed", origin) + return + } + + reqMethod := r.Header.Get("Access-Control-Request-Method") + if !cors.isMethodAllowed(reqMethod) { + cors.logf(" Preflight aborted: method '%s' not allowed", reqMethod) + return + } + reqHeaders := parseHeaderList(r.Header.Get("Access-Control-Request-Headers")) + if !cors.areHeadersAllowed(reqHeaders) { + cors.logf(" Preflight aborted: headers '%v' not allowed", reqHeaders) + return + } + headers.Set("Access-Control-Allow-Origin", origin) + headers.Add("Vary", "Origin") + // Spec says: Since the list of methods can be unbounded, simply returning the method indicated + // by Access-Control-Request-Method (if supported) can be enough + headers.Set("Access-Control-Allow-Methods", strings.ToUpper(reqMethod)) + if len(reqHeaders) > 0 { + + // Spec says: Since the list of headers can be unbounded, simply returning supported headers + // from Access-Control-Request-Headers can be enough + headers.Set("Access-Control-Allow-Headers", strings.Join(reqHeaders, ", ")) + } + if options.AllowCredentials { + headers.Set("Access-Control-Allow-Credentials", "true") + } + if options.MaxAge > 0 { + headers.Set("Access-Control-Max-Age", strconv.Itoa(options.MaxAge)) + } + cors.logf(" Preflight response headers: %v", headers) +} + +// handleActualRequest handles simple cross-origin requests, actual request or redirects +func (cors *Cors) handleActualRequest(w http.ResponseWriter, r *http.Request) { + options := cors.options + headers := w.Header() + origin := r.Header.Get("Origin") + + if r.Method == "OPTIONS" { + cors.logf(" Actual request no headers added: method == %s", r.Method) + return + } + if origin == "" { + cors.logf(" Actual request no headers added: missing origin") + return + } + if !cors.isOriginAllowed(origin) { + cors.logf(" Actual request no headers added: origin '%s' not allowed", origin) + return + } + + // Note that spec does define a way to specifically disallow a simple method like GET or + // POST. Access-Control-Allow-Methods is only used for pre-flight requests and the + // spec doesn't instruct to check the allowed methods for simple cross-origin requests. + // We think it's a nice feature to be able to have control on those methods though. + if !cors.isMethodAllowed(r.Method) { + if cors.options.Debug { + cors.logf(" Actual request no headers added: method '%s' not allowed", + r.Method) + } + + return + } + headers.Set("Access-Control-Allow-Origin", origin) + headers.Add("Vary", "Origin") + if len(options.ExposedHeaders) > 0 { + headers.Set("Access-Control-Expose-Headers", strings.Join(options.ExposedHeaders, ", ")) + } + if options.AllowCredentials { + headers.Set("Access-Control-Allow-Credentials", "true") + } + cors.logf(" Actual response added headers: %v", headers) +} + +// convenience method. checks if debugging is turned on before printing +func (cors *Cors) logf(format string, a ...interface{}) { + if cors.options.Debug { + cors.options.log.Printf(format, a...) + } +} + +// isOriginAllowed checks if a given origin is allowed to perform cross-domain requests +// on the endpoint +func (cors *Cors) isOriginAllowed(origin string) bool { + allowedOrigins := cors.options.AllowedOrigins + origin = strings.ToLower(origin) + for _, allowedOrigin := range allowedOrigins { + switch allowedOrigin { + case "*": + return true + case origin: + return true + } + } + return false +} + +// isMethodAllowed checks if a given method can be used as part of a cross-domain request +// on the endpoing +func (cors *Cors) isMethodAllowed(method string) bool { + allowedMethods := cors.options.AllowedMethods + if len(allowedMethods) == 0 { + // If no method allowed, always return false, even for preflight request + return false + } + method = strings.ToUpper(method) + if method == "OPTIONS" { + // Always allow preflight requests + return true + } + for _, allowedMethod := range allowedMethods { + if allowedMethod == method { + return true + } + } + return false +} + +// areHeadersAllowed checks if a given list of headers are allowed to used within +// a cross-domain request. +func (cors *Cors) areHeadersAllowed(requestedHeaders []string) bool { + if len(requestedHeaders) == 0 { + return true + } + for _, header := range requestedHeaders { + found := false + for _, allowedHeader := range cors.options.AllowedHeaders { + if allowedHeader == "*" || allowedHeader == header { + found = true + break + } + } + if !found { + return false + } + } + return true +} diff --git a/Godeps/_workspace/src/github.com/rs/cors/utils.go b/Godeps/_workspace/src/github.com/rs/cors/utils.go new file mode 100644 index 000000000..429ab1114 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/cors/utils.go @@ -0,0 +1,27 @@ +package cors + +import ( + "net/http" + "strings" +) + +type converter func(string) string + +// convert converts a list of string using the passed converter function +func convert(s []string, c converter) []string { + out := []string{} + for _, i := range s { + out = append(out, c(i)) + } + return out +} + +func parseHeaderList(headerList string) (headers []string) { + for _, header := range strings.Split(headerList, ",") { + header = http.CanonicalHeaderKey(strings.TrimSpace(header)) + if header != "" { + headers = append(headers, header) + } + } + return headers +} diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/.travis.yml b/Godeps/_workspace/src/github.com/rs/xhandler/.travis.yml new file mode 100644 index 000000000..b65c7a9f1 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/.travis.yml @@ -0,0 +1,7 @@ +language: go +go: +- 1.5 +- tip +matrix: + allow_failures: + - go: tip diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/LICENSE b/Godeps/_workspace/src/github.com/rs/xhandler/LICENSE new file mode 100644 index 000000000..47c5e9d2d --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/LICENSE @@ -0,0 +1,19 @@ +Copyright (c) 2015 Olivier Poitrey + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is furnished +to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/README.md b/Godeps/_workspace/src/github.com/rs/xhandler/README.md new file mode 100644 index 000000000..91c594bd2 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/README.md @@ -0,0 +1,134 @@ +# XHandler + +[![godoc](http://img.shields.io/badge/godoc-reference-blue.svg?style=flat)](https://godoc.org/github.com/rs/xhandler) [![license](http://img.shields.io/badge/license-MIT-red.svg?style=flat)](https://raw.githubusercontent.com/rs/xhandler/master/LICENSE) [![Build Status](https://travis-ci.org/rs/xhandler.svg?branch=master)](https://travis-ci.org/rs/xhandler) [![Coverage](http://gocover.io/_badge/github.com/rs/xhandler)](http://gocover.io/github.com/rs/xhandler) + +XHandler is a bridge between [net/context](https://godoc.org/golang.org/x/net/context) and `http.Handler`. + +It lets you enforce `net/context` in your handlers without sacrificing compatibility with existing `http.Handlers` nor imposing a specific router. + +Thanks to `net/context` deadline management, `xhandler` is able to enforce a per request deadline and will cancel the context when the client closes the connection unexpectedly. + +You may create your own `net/context` aware handler pretty much the same way as you would do with http.Handler. + +Read more about xhandler on [Dailymotion engineering blog](http://engineering.dailymotion.com/our-way-to-go/). + +## Installing + + go get -u github.com/rs/xhandler + +## Usage + +```go +package main + +import ( + "log" + "net/http" + "time" + + "github.com/rs/cors" + "github.com/rs/xhandler" + "golang.org/x/net/context" +) + +type myMiddleware struct { + next xhandler.HandlerC +} + +func (h myMiddleware) ServeHTTPC(ctx context.Context, w http.ResponseWriter, r *http.Request) { + ctx = context.WithValue(ctx, "test", "World") + h.next.ServeHTTPC(ctx, w, r) +} + +func main() { + c := xhandler.Chain{} + + // Add close notifier handler so context is cancelled when the client closes + // the connection + c.UseC(xhandler.CloseHandler) + + // Add timeout handler + c.UseC(xhandler.TimeoutHandler(2 * time.Second)) + + // Middleware putting something in the context + c.UseC(func(next xhandler.HandlerC) xhandler.HandlerC { + return myMiddleware{next: next} + }) + + // Mix it with a non-context-aware middleware handler + c.Use(cors.Default().Handler) + + // Final handler (using handlerFuncC), reading from the context + xh := xhandler.HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + value := ctx.Value("test").(string) + w.Write([]byte("Hello " + value)) + }) + + // Bridge context aware handlers with http.Handler using xhandler.Handle() + http.Handle("/test", c.Handler(xh)) + + if err := http.ListenAndServe(":8080", nil); err != nil { + log.Fatal(err) + } +} +``` + +### Using xmux + +Xhandler comes with an optional context aware [muxer](https://github.com/rs/xmux) forked from [httprouter](https://github.com/julienschmidt/httprouter): + +```go +package main + +import ( + "fmt" + "log" + "net/http" + "time" + + "github.com/rs/xhandler" + "github.com/rs/xmux" + "golang.org/x/net/context" +) + +func main() { + c := xhandler.Chain{} + + // Append a context-aware middleware handler + c.UseC(xhandler.CloseHandler) + + // Another context-aware middleware handler + c.UseC(xhandler.TimeoutHandler(2 * time.Second)) + + mux := xmux.New() + + // Use c.Handler to terminate the chain with your final handler + mux.GET("/welcome/:name", xhandler.HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, req *http.Request) { + fmt.Fprintf(w, "Welcome %s!", xmux.Params(ctx).Get("name")) + })) + + if err := http.ListenAndServe(":8080", c.Handler(mux)); err != nil { + log.Fatal(err) + } +} +``` + +See [xmux](https://github.com/rs/xmux) for more examples. + +## Context Aware Middleware + +Here is a list of `net/context` aware middleware handlers implementing `xhandler.HandlerC` interface. + +Feel free to put up a PR linking your middleware if you have built one: + +| Middleware | Author | Description | +| ---------- | ------ | ----------- | +| [xmux](https://github.com/rs/xmux) | [Olivier Poitrey](https://github.com/rs) | HTTP request muxer | +| [xlog](https://github.com/rs/xlog) | [Olivier Poitrey](https://github.com/rs) | HTTP handler logger | +| [xstats](https://github.com/rs/xstats) | [Olivier Poitrey](https://github.com/rs) | A generic client for service instrumentation | +| [xaccess](https://github.com/rs/xaccess) | [Olivier Poitrey](https://github.com/rs) | HTTP handler access logger with [xlog](https://github.com/rs/xlog) and [xstats](https://github.com/rs/xstats) | +| [cors](https://github.com/rs/cors) | [Olivier Poitrey](https://github.com/rs) | [Cross Origin Resource Sharing](http://www.w3.org/TR/cors/) (CORS) support | + +## Licenses + +All source code is licensed under the [MIT License](https://raw.github.com/rs/xhandler/master/LICENSE). diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/chain.go b/Godeps/_workspace/src/github.com/rs/xhandler/chain.go new file mode 100644 index 000000000..ffac67e8a --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/chain.go @@ -0,0 +1,93 @@ +package xhandler + +import ( + "net/http" + + "github.com/ethereum/go-ethereum/Godeps/_workspace/src/golang.org/x/net/context" +) + +// Chain is an helper to chain middleware handlers together for an easier +// management. +type Chain []func(next HandlerC) HandlerC + +// UseC appends a context-aware handler to the middleware chain. +func (c *Chain) UseC(f func(next HandlerC) HandlerC) { + *c = append(*c, f) +} + +// Use appends a standard http.Handler to the middleware chain without +// lossing track of the context when inserted between two context aware handlers. +// +// Caveat: the f function will be called on each request so you are better to put +// any initialization sequence outside of this function. +func (c *Chain) Use(f func(next http.Handler) http.Handler) { + xf := func(next HandlerC) HandlerC { + return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + n := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + next.ServeHTTPC(ctx, w, r) + }) + f(n).ServeHTTP(w, r) + }) + } + *c = append(*c, xf) +} + +// Handler wraps the provided final handler with all the middleware appended to +// the chain and return a new standard http.Handler instance. +// The context.Background() context is injected automatically. +func (c Chain) Handler(xh HandlerC) http.Handler { + ctx := context.Background() + return c.HandlerCtx(ctx, xh) +} + +// HandlerFC is an helper to provide a function (HandlerFuncC) to Handler(). +// +// HandlerFC is equivalent to: +// c.Handler(xhandler.HandlerFuncC(xhc)) +func (c Chain) HandlerFC(xhf HandlerFuncC) http.Handler { + ctx := context.Background() + return c.HandlerCtx(ctx, HandlerFuncC(xhf)) +} + +// HandlerH is an helper to provide a standard http handler (http.HandlerFunc) +// to Handler(). Your final handler won't have access the context though. +func (c Chain) HandlerH(h http.Handler) http.Handler { + ctx := context.Background() + return c.HandlerCtx(ctx, HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + h.ServeHTTP(w, r) + })) +} + +// HandlerF is an helper to provide a standard http handler function +// (http.HandlerFunc) to Handler(). Your final handler won't have access +// the context though. +func (c Chain) HandlerF(hf http.HandlerFunc) http.Handler { + ctx := context.Background() + return c.HandlerCtx(ctx, HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + hf(w, r) + })) +} + +// HandlerCtx wraps the provided final handler with all the middleware appended to +// the chain and return a new standard http.Handler instance. +func (c Chain) HandlerCtx(ctx context.Context, xh HandlerC) http.Handler { + return New(ctx, c.HandlerC(xh)) +} + +// HandlerC wraps the provided final handler with all the middleware appended to +// the chain and returns a HandlerC instance. +func (c Chain) HandlerC(xh HandlerC) HandlerC { + for i := len(c) - 1; i >= 0; i-- { + xh = c[i](xh) + } + return xh +} + +// HandlerCF wraps the provided final handler func with all the middleware appended to +// the chain and returns a HandlerC instance. +// +// HandlerCF is equivalent to: +// c.HandlerC(xhandler.HandlerFuncC(xhc)) +func (c Chain) HandlerCF(xhc HandlerFuncC) HandlerC { + return c.HandlerC(HandlerFuncC(xhc)) +} diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/middleware.go b/Godeps/_workspace/src/github.com/rs/xhandler/middleware.go new file mode 100644 index 000000000..64b180323 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/middleware.go @@ -0,0 +1,59 @@ +package xhandler + +import ( + "net/http" + "time" + + "github.com/ethereum/go-ethereum/Godeps/_workspace/src/golang.org/x/net/context" +) + +// CloseHandler returns a Handler cancelling the context when the client +// connection close unexpectedly. +func CloseHandler(next HandlerC) HandlerC { + return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + // Cancel the context if the client closes the connection + if wcn, ok := w.(http.CloseNotifier); ok { + var cancel context.CancelFunc + ctx, cancel = context.WithCancel(ctx) + defer cancel() + + notify := wcn.CloseNotify() + go func() { + select { + case <-notify: + cancel() + case <-ctx.Done(): + } + }() + } + + next.ServeHTTPC(ctx, w, r) + }) +} + +// TimeoutHandler returns a Handler which adds a timeout to the context. +// +// Child handlers have the responsability to obey the context deadline and to return +// an appropriate error (or not) response in case of timeout. +func TimeoutHandler(timeout time.Duration) func(next HandlerC) HandlerC { + return func(next HandlerC) HandlerC { + return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + ctx, _ = context.WithTimeout(ctx, timeout) + next.ServeHTTPC(ctx, w, r) + }) + } +} + +// If is a special handler that will skip insert the condNext handler only if a condition +// applies at runtime. +func If(cond func(ctx context.Context, w http.ResponseWriter, r *http.Request) bool, condNext func(next HandlerC) HandlerC) func(next HandlerC) HandlerC { + return func(next HandlerC) HandlerC { + return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) { + if cond(ctx, w, r) { + condNext(next).ServeHTTPC(ctx, w, r) + } else { + next.ServeHTTPC(ctx, w, r) + } + }) + } +} diff --git a/Godeps/_workspace/src/github.com/rs/xhandler/xhandler.go b/Godeps/_workspace/src/github.com/rs/xhandler/xhandler.go new file mode 100644 index 000000000..b71789804 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rs/xhandler/xhandler.go @@ -0,0 +1,42 @@ +// Package xhandler provides a bridge between http.Handler and net/context. +// +// xhandler enforces net/context in your handlers without sacrificing +// compatibility with existing http.Handlers nor imposing a specific router. +// +// Thanks to net/context deadline management, xhandler is able to enforce +// a per request deadline and will cancel the context in when the client close +// the connection unexpectedly. +// +// You may create net/context aware middlewares pretty much the same way as +// you would do with http.Handler. +package xhandler + +import ( + "net/http" + + "github.com/ethereum/go-ethereum/Godeps/_workspace/src/golang.org/x/net/context" +) + +// HandlerC is a net/context aware http.Handler +type HandlerC interface { + ServeHTTPC(context.Context, http.ResponseWriter, *http.Request) +} + +// HandlerFuncC type is an adapter to allow the use of ordinary functions +// as a xhandler.Handler. If f is a function with the appropriate signature, +// xhandler.HandlerFuncC(f) is a xhandler.Handler object that calls f. +type HandlerFuncC func(context.Context, http.ResponseWriter, *http.Request) + +// ServeHTTPC calls f(ctx, w, r). +func (f HandlerFuncC) ServeHTTPC(ctx context.Context, w http.ResponseWriter, r *http.Request) { + f(ctx, w, r) +} + +// New creates a conventional http.Handler injecting the provided root +// context to sub handlers. This handler is used as a bridge between conventional +// http.Handler and context aware handlers. +func New(ctx context.Context, h HandlerC) http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + h.ServeHTTPC(ctx, w, r) + }) +} diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go index 69fb0b9db..07265ee20 100644 --- a/cmd/utils/flags.go +++ b/cmd/utils/flags.go @@ -245,7 +245,7 @@ var ( } RPCCORSDomainFlag = cli.StringFlag{ Name: "rpccorsdomain", - Usage: "Domains from which to accept cross origin requests (browser enforced)", + Usage: "Comma separated list of domains from which to accept cross origin requests (browser enforced)", Value: "", } RPCApiFlag = cli.StringFlag{ diff --git a/rpc/http.go b/rpc/http.go index d9053b003..af3d29014 100644 --- a/rpc/http.go +++ b/rpc/http.go @@ -17,240 +17,23 @@ package rpc import ( - "bufio" "bytes" "encoding/json" "fmt" - "io" "io/ioutil" - "net" "net/http" "net/url" - "strconv" "strings" - "time" - "github.com/ethereum/go-ethereum/logger" - "github.com/ethereum/go-ethereum/logger/glog" - "gopkg.in/fatih/set.v0" + "io" + + "github.com/rs/cors" ) const ( - httpReadDeadLine = 60 * time.Second // wait max httpReadDeadeline for next request + maxHTTPRequestContentLength = 1024 * 128 ) -// httpMessageStream is the glue between a HTTP connection which is message based -// and the RPC codecs that expect json requests to be read from a stream. It will -// parse HTTP messages and offer the bodies of these requests as a stream through -// the Read method. This will require full control of the connection and thus need -// a "hijacked" HTTP connection. -type httpMessageStream struct { - conn net.Conn // TCP connection - rw *bufio.ReadWriter // buffered where HTTP requests/responses are read/written from/to - currentReq *http.Request // pending request, codec can pass in a too small buffer for a single read we need to keep track of the current requests if it was not read at once - payloadBytesRead int64 // number of bytes which are read from the current request - allowedOrigins *set.Set // allowed CORS domains - origin string // origin of this connection/request -} - -// NewHttpMessageStream will create a new http message stream parser that can be -// used by the codes in the RPC package. It will take full control of the given -// connection and thus needs to be hijacked. It will read and write HTTP messages -// from the passed rwbuf. The allowed origins are the RPC CORS domains the user has supplied. -func NewHTTPMessageStream(c net.Conn, rwbuf *bufio.ReadWriter, initialReq *http.Request, allowdOrigins []string) *httpMessageStream { - r := &httpMessageStream{conn: c, rw: rwbuf, currentReq: initialReq, allowedOrigins: set.New()} - for _, origin := range allowdOrigins { - r.allowedOrigins.Add(origin) - } - return r -} - -// handleOptionsRequest handles the HTTP preflight requests (OPTIONS) that browsers -// make to enforce CORS rules. Only the POST method is allowed and the origin must -// be on the rpccorsdomain list the user has specified. -func (h *httpMessageStream) handleOptionsRequest(req *http.Request) error { - headers := req.Header - - if !strings.EqualFold(req.Method, "OPTIONS") { - return fmt.Errorf("preflight aborted: %s!=OPTIONS", req.Method) - } - - origin := headers.Get("Origin") - if origin == "" { - return fmt.Errorf("preflight aborted: empty origin") - } - - responseHeaders := make(http.Header) - responseHeaders.Set("Access-Control-Allow-Methods", "POST") - if h.allowedOrigins.Has(origin) || h.allowedOrigins.Has("*") { - responseHeaders.Set("Access-Control-Allow-Origin", origin) - } else { - glog.V(logger.Info).Infof("origin '%s' not allowed", origin) - } - responseHeaders.Set("Access-Control-Allow-Headers", "Content-Type") - responseHeaders.Set("Date", string(httpTimestamp(time.Now()))) - responseHeaders.Set("Content-Type", "text/plain; charset=utf-8") - responseHeaders.Set("Content-Length", "0") - responseHeaders.Set("Vary", "Origin") - - defer h.rw.Flush() - - if _, err := h.rw.WriteString("HTTP/1.1 200 OK\r\n"); err != nil { - glog.V(logger.Error).Infof("unable to write OPTIONS response: %v\n", err) - return err - } - if err := responseHeaders.Write(h.rw); err != nil { - glog.V(logger.Error).Infof("unable to write OPTIONS headers: %v\n", err) - } - if _, err := h.rw.WriteString("\r\n"); err != nil { - glog.V(logger.Error).Infof("unable to write OPTIONS response: %v\n", err) - } - - return nil -} - -// Read will read incoming HTTP requests and reads the body data from these requests -// as an endless stream of data. -func (h *httpMessageStream) Read(buf []byte) (n int, err error) { - h.conn.SetReadDeadline(time.Now().Add(httpReadDeadLine)) - for { - // if the last request was read completely try to read the next request - if h.currentReq == nil { - if h.currentReq, err = http.ReadRequest(bufio.NewReader(h.rw)); err != nil { - return 0, err - } - } - - // The "options" method is http specific and not interested for the RPC server. - // Handle it internally and wait for the next request. - if strings.EqualFold(h.currentReq.Method, "OPTIONS") { - if err = h.handleOptionsRequest(h.currentReq); err != nil { - glog.V(logger.Info).Infof("RPC/HTTP OPTIONS error: %v\n", err) - h.currentReq = nil - return 0, err - } - - // processed valid request -> reset deadline - h.conn.SetReadDeadline(time.Now().Add(httpReadDeadLine)) - h.currentReq = nil - continue - } - - if strings.EqualFold(h.currentReq.Method, "GET") || strings.EqualFold(h.currentReq.Method, "POST") { - n, err := h.currentReq.Body.Read(buf) - h.payloadBytesRead += int64(n) - - // entire payload read, read new request next time - if err == io.EOF || h.payloadBytesRead >= h.currentReq.ContentLength { - h.origin = h.currentReq.Header.Get("origin") - h.payloadBytesRead = 0 - h.currentReq.Body.Close() - h.currentReq = nil - err = nil // io.EOF is not an error - } else if err != nil { - // unable to read body - h.currentReq.Body.Close() - h.currentReq = nil - h.payloadBytesRead = 0 - } - // partial read of body - return n, err - } - return 0, fmt.Errorf("unsupported HTTP method '%s'", h.currentReq.Method) - } -} - -// Write will create a HTTP response with the given payload and send it to the peer. -func (h *httpMessageStream) Write(payload []byte) (int, error) { - defer h.rw.Flush() - - responseHeaders := make(http.Header) - responseHeaders.Set("Content-Type", "application/json") - responseHeaders.Set("Content-Length", strconv.Itoa(len(payload))) - if h.origin != "" { - responseHeaders.Set("Access-Control-Allow-Origin", h.origin) - } - - h.rw.WriteString("HTTP/1.1 200 OK\r\n") - responseHeaders.Write(h.rw) - h.rw.WriteString("\r\n") - - return h.rw.Write(payload) -} - -// Close will close the underlying TCP connection this instance has taken ownership over. -func (h *httpMessageStream) Close() error { - h.rw.Flush() - return h.conn.Close() -} - -// TimeFormat is the time format to use with time.Parse and time.Time.Format when -// parsing or generating times in HTTP headers. It is like time.RFC1123 but hard -// codes GMT as the time zone. -const TimeFormat = "Mon, 02 Jan 2006 15:04:05 GMT" - -// httpTimestamp formats the given t as specified in RFC1123. -func httpTimestamp(t time.Time) []byte { - const days = "SunMonTueWedThuFriSat" - const months = "JanFebMarAprMayJunJulAugSepOctNovDec" - - b := make([]byte, 0) - t = t.UTC() - yy, mm, dd := t.Date() - hh, mn, ss := t.Clock() - day := days[3*t.Weekday():] - mon := months[3*(mm-1):] - - return append(b, - day[0], day[1], day[2], ',', ' ', - byte('0'+dd/10), byte('0'+dd%10), ' ', - mon[0], mon[1], mon[2], ' ', - byte('0'+yy/1000), byte('0'+(yy/100)%10), byte('0'+(yy/10)%10), byte('0'+yy%10), ' ', - byte('0'+hh/10), byte('0'+hh%10), ':', - byte('0'+mn/10), byte('0'+mn%10), ':', - byte('0'+ss/10), byte('0'+ss%10), ' ', - 'G', 'M', 'T') -} - -// httpConnHijacker is a http.Handler implementation that will hijack the HTTP -// connection, wraps it in a HttpMessageStream that is then wrapped in a JSON -// codec which will be served on the rpcServer. -type httpConnHijacker struct { - corsdomains []string - rpcServer *Server -} - -// ServeHTTP will hijack the connection, wraps the captured connection in a -// HttpMessageStream which is then used as codec. -func (h *httpConnHijacker) ServeHTTP(w http.ResponseWriter, req *http.Request) { - hj, ok := w.(http.Hijacker) - if !ok { - http.Error(w, "webserver doesn't support hijacking", http.StatusInternalServerError) - return - } - - conn, rwbuf, err := hj.Hijack() - if err != nil { - http.Error(w, err.Error(), http.StatusInternalServerError) - return - } - - httpRequestStream := NewHTTPMessageStream(conn, rwbuf, req, h.corsdomains) - - codec := NewJSONCodec(httpRequestStream) - go h.rpcServer.ServeCodec(codec) -} - -// NewHTTPServer creates a new HTTP RPC server around an API provider. -func NewHTTPServer(cors string, handler *Server) *http.Server { - return &http.Server{ - Handler: &httpConnHijacker{ - corsdomains: strings.Split(cors, ","), - rpcServer: handler, - }, - } -} - // httpClient connects to a geth RPC server over HTTP. type httpClient struct { endpoint *url.URL // HTTP-RPC server endpoint @@ -313,3 +96,55 @@ func (client *httpClient) Close() { func (client *httpClient) SupportedModules() (map[string]string, error) { return SupportedModules(client) } + +// httpReadWriteNopCloser wraps a io.Reader and io.Writer with a NOP Close method. +type httpReadWriteNopCloser struct { + io.Reader + io.Writer +} + +// Close does nothing and returns always nil +func (t *httpReadWriteNopCloser) Close() error { + return nil +} + +// newJSONHTTPHandler creates a HTTP handler that will parse incoming JSON requests, +// send the request to the given API provider and sends the response back to the caller. +func newJSONHTTPHandler(srv *Server) http.HandlerFunc { + return func(w http.ResponseWriter, r *http.Request) { + if r.ContentLength > maxHTTPRequestContentLength { + http.Error(w, + fmt.Sprintf("content length too large (%d>%d)", r.ContentLength, maxHTTPRequestContentLength), + http.StatusRequestEntityTooLarge) + return + } + + w.Header().Set("content-type", "application/json") + + // create a codec that reads direct from the request body until + // EOF and writes the response to w and order the server to process + // a single request. + codec := NewJSONCodec(&httpReadWriteNopCloser{r.Body, w}) + defer codec.Close() + srv.ServeSingleRequest(codec) + } +} + +// NewHTTPServer creates a new HTTP RPC server around an API provider. +func NewHTTPServer(corsString string, srv *Server) *http.Server { + var allowedOrigins []string + for _, domain := range strings.Split(corsString, ",") { + allowedOrigins = append(allowedOrigins, strings.TrimSpace(domain)) + } + + c := cors.New(cors.Options{ + AllowedOrigins: allowedOrigins, + AllowedMethods: []string{"POST", "GET"}, + }) + + handler := c.Handler(newJSONHTTPHandler(srv)) + + return &http.Server{ + Handler: handler, + } +} diff --git a/rpc/server.go b/rpc/server.go index f42ee2d37..22448f8e3 100644 --- a/rpc/server.go +++ b/rpc/server.go @@ -117,14 +117,12 @@ func (s *Server) RegisterName(name string, rcvr interface{}) error { return nil } -// ServeCodec reads incoming requests from codec, calls the appropriate callback and writes the -// response back using the given codec. It will block until the codec is closed. -// -// This server will: -// 1. allow for asynchronous and parallel request execution -// 2. supports notifications (pub/sub) -// 3. supports request batches -func (s *Server) ServeCodec(codec ServerCodec) { +// serveRequest will reads requests from the codec, calls the RPC callback and +// writes the response to the given codec. +// If singleShot is true it will process a single request, otherwise it will handle +// requests until the codec returns an error when reading a request (in most cases +// an EOF). It executes requests in parallel when singleShot is false. +func (s *Server) serveRequest(codec ServerCodec, singleShot bool) error { defer func() { if err := recover(); err != nil { const size = 64 << 10 @@ -132,7 +130,12 @@ func (s *Server) ServeCodec(codec ServerCodec) { buf = buf[:runtime.Stack(buf, false)] glog.Errorln(string(buf)) } - codec.Close() + + s.codecsMu.Lock() + s.codecs.Remove(codec) + s.codecsMu.Unlock() + + return }() ctx, cancel := context.WithCancel(context.Background()) @@ -141,20 +144,22 @@ func (s *Server) ServeCodec(codec ServerCodec) { s.codecsMu.Lock() if atomic.LoadInt32(&s.run) != 1 { // server stopped s.codecsMu.Unlock() - return + return &shutdownError{} } s.codecs.Add(codec) s.codecsMu.Unlock() + // test if the server is ordered to stop for atomic.LoadInt32(&s.run) == 1 { reqs, batch, err := s.readRequest(codec) - if err != nil { glog.V(logger.Debug).Infof("%v\n", err) codec.Write(codec.CreateErrorResponse(nil, err)) - break + return nil } + // check if server is ordered to shutdown and return an error + // telling the client that his request failed. if atomic.LoadInt32(&s.run) != 1 { err = &shutdownError{} if batch { @@ -166,15 +171,42 @@ func (s *Server) ServeCodec(codec ServerCodec) { } else { codec.Write(codec.CreateErrorResponse(&reqs[0].id, err)) } - break + return nil } - if batch { + if singleShot && batch { + s.execBatch(ctx, codec, reqs) + return nil + } else if singleShot && !batch { + s.exec(ctx, codec, reqs[0]) + return nil + } else if !singleShot && batch { go s.execBatch(ctx, codec, reqs) } else { go s.exec(ctx, codec, reqs[0]) } } + + return nil +} + +// ServeCodec reads incoming requests from codec, calls the appropriate callback and writes the +// response back using the given codec. It will block until the codec is closed or the server is +// stopped. In either case the codec is closed. +// +// This server will: +// 1. allow for asynchronous and parallel request execution +// 2. supports notifications (pub/sub) +// 3. supports request batches +func (s *Server) ServeCodec(codec ServerCodec) { + defer codec.Close() + s.serveRequest(codec, false) +} + +// ServeSingleRequest reads and processes a single RPC request from the given codec. It will not +// close the codec unless a non-recoverable error has occurred. +func (s *Server) ServeSingleRequest(codec ServerCodec) { + s.serveRequest(codec, true) } // Stop will stop reading new requests, wait for stopPendingRequestTimeout to allow pending requests to finish,