commit 4aa2e2eaa01e04e05cfbcd765afb5059ff85b8e1 Author: Frederick F. Kautz IV Date: Sat Nov 1 21:03:30 2014 -0700 Squashed 'third_party/src/github.com/gorilla/context/' content from commit 14f550f git-subtree-dir: third_party/src/github.com/gorilla/context git-subtree-split: 14f550f51af52180c2eefed15e5fd18d63c0a64a diff --git a/.travis.yml b/.travis.yml new file mode 100644 index 000000000..d87d46576 --- /dev/null +++ b/.travis.yml @@ -0,0 +1,7 @@ +language: go + +go: + - 1.0 + - 1.1 + - 1.2 + - tip diff --git a/LICENSE b/LICENSE new file mode 100644 index 000000000..0e5fb8728 --- /dev/null +++ b/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/README.md b/README.md new file mode 100644 index 000000000..c60a31b05 --- /dev/null +++ b/README.md @@ -0,0 +1,7 @@ +context +======= +[![Build Status](https://travis-ci.org/gorilla/context.png?branch=master)](https://travis-ci.org/gorilla/context) + +gorilla/context is a general purpose registry for global request variables. + +Read the full documentation here: http://www.gorillatoolkit.org/pkg/context diff --git a/context.go b/context.go new file mode 100644 index 000000000..81cb128b1 --- /dev/null +++ b/context.go @@ -0,0 +1,143 @@ +// 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 context + +import ( + "net/http" + "sync" + "time" +) + +var ( + mutex sync.RWMutex + data = make(map[*http.Request]map[interface{}]interface{}) + datat = make(map[*http.Request]int64) +) + +// Set stores a value for a given key in a given request. +func Set(r *http.Request, key, val interface{}) { + mutex.Lock() + if data[r] == nil { + data[r] = make(map[interface{}]interface{}) + datat[r] = time.Now().Unix() + } + data[r][key] = val + mutex.Unlock() +} + +// Get returns a value stored for a given key in a given request. +func Get(r *http.Request, key interface{}) interface{} { + mutex.RLock() + if ctx := data[r]; ctx != nil { + value := ctx[key] + mutex.RUnlock() + return value + } + mutex.RUnlock() + return nil +} + +// GetOk returns stored value and presence state like multi-value return of map access. +func GetOk(r *http.Request, key interface{}) (interface{}, bool) { + mutex.RLock() + if _, ok := data[r]; ok { + value, ok := data[r][key] + mutex.RUnlock() + return value, ok + } + mutex.RUnlock() + return nil, false +} + +// GetAll returns all stored values for the request as a map. Nil is returned for invalid requests. +func GetAll(r *http.Request) map[interface{}]interface{} { + mutex.RLock() + if context, ok := data[r]; ok { + result := make(map[interface{}]interface{}, len(context)) + for k, v := range context { + result[k] = v + } + mutex.RUnlock() + return result + } + mutex.RUnlock() + return nil +} + +// GetAllOk returns all stored values for the request as a map and a boolean value that indicates if +// the request was registered. +func GetAllOk(r *http.Request) (map[interface{}]interface{}, bool) { + mutex.RLock() + context, ok := data[r] + result := make(map[interface{}]interface{}, len(context)) + for k, v := range context { + result[k] = v + } + mutex.RUnlock() + return result, ok +} + +// Delete removes a value stored for a given key in a given request. +func Delete(r *http.Request, key interface{}) { + mutex.Lock() + if data[r] != nil { + delete(data[r], key) + } + mutex.Unlock() +} + +// Clear removes all values stored for a given request. +// +// This is usually called by a handler wrapper to clean up request +// variables at the end of a request lifetime. See ClearHandler(). +func Clear(r *http.Request) { + mutex.Lock() + clear(r) + mutex.Unlock() +} + +// clear is Clear without the lock. +func clear(r *http.Request) { + delete(data, r) + delete(datat, r) +} + +// Purge removes request data stored for longer than maxAge, in seconds. +// It returns the amount of requests removed. +// +// If maxAge <= 0, all request data is removed. +// +// This is only used for sanity check: in case context cleaning was not +// properly set some request data can be kept forever, consuming an increasing +// amount of memory. In case this is detected, Purge() must be called +// periodically until the problem is fixed. +func Purge(maxAge int) int { + mutex.Lock() + count := 0 + if maxAge <= 0 { + count = len(data) + data = make(map[*http.Request]map[interface{}]interface{}) + datat = make(map[*http.Request]int64) + } else { + min := time.Now().Unix() - int64(maxAge) + for r := range data { + if datat[r] < min { + clear(r) + count++ + } + } + } + mutex.Unlock() + return count +} + +// ClearHandler wraps an http.Handler and clears request values at the end +// of a request lifetime. +func ClearHandler(h http.Handler) http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + defer Clear(r) + h.ServeHTTP(w, r) + }) +} diff --git a/context_test.go b/context_test.go new file mode 100644 index 000000000..6ada8ec31 --- /dev/null +++ b/context_test.go @@ -0,0 +1,161 @@ +// 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 context + +import ( + "net/http" + "testing" +) + +type keyType int + +const ( + key1 keyType = iota + key2 +) + +func TestContext(t *testing.T) { + assertEqual := func(val interface{}, exp interface{}) { + if val != exp { + t.Errorf("Expected %v, got %v.", exp, val) + } + } + + r, _ := http.NewRequest("GET", "http://localhost:8080/", nil) + emptyR, _ := http.NewRequest("GET", "http://localhost:8080/", nil) + + // Get() + assertEqual(Get(r, key1), nil) + + // Set() + Set(r, key1, "1") + assertEqual(Get(r, key1), "1") + assertEqual(len(data[r]), 1) + + Set(r, key2, "2") + assertEqual(Get(r, key2), "2") + assertEqual(len(data[r]), 2) + + //GetOk + value, ok := GetOk(r, key1) + assertEqual(value, "1") + assertEqual(ok, true) + + value, ok = GetOk(r, "not exists") + assertEqual(value, nil) + assertEqual(ok, false) + + Set(r, "nil value", nil) + value, ok = GetOk(r, "nil value") + assertEqual(value, nil) + assertEqual(ok, true) + + // GetAll() + values := GetAll(r) + assertEqual(len(values), 3) + + // GetAll() for empty request + values = GetAll(emptyR) + if values != nil { + t.Error("GetAll didn't return nil value for invalid request") + } + + // GetAllOk() + values, ok = GetAllOk(r) + assertEqual(len(values), 3) + assertEqual(ok, true) + + // GetAllOk() for empty request + values, ok = GetAllOk(emptyR) + assertEqual(value, nil) + assertEqual(ok, false) + + // Delete() + Delete(r, key1) + assertEqual(Get(r, key1), nil) + assertEqual(len(data[r]), 2) + + Delete(r, key2) + assertEqual(Get(r, key2), nil) + assertEqual(len(data[r]), 1) + + // Clear() + Clear(r) + assertEqual(len(data), 0) +} + +func parallelReader(r *http.Request, key string, iterations int, wait, done chan struct{}) { + <-wait + for i := 0; i < iterations; i++ { + Get(r, key) + } + done <- struct{}{} + +} + +func parallelWriter(r *http.Request, key, value string, iterations int, wait, done chan struct{}) { + <-wait + for i := 0; i < iterations; i++ { + Get(r, key) + } + done <- struct{}{} + +} + +func benchmarkMutex(b *testing.B, numReaders, numWriters, iterations int) { + + b.StopTimer() + r, _ := http.NewRequest("GET", "http://localhost:8080/", nil) + done := make(chan struct{}) + b.StartTimer() + + for i := 0; i < b.N; i++ { + wait := make(chan struct{}) + + for i := 0; i < numReaders; i++ { + go parallelReader(r, "test", iterations, wait, done) + } + + for i := 0; i < numWriters; i++ { + go parallelWriter(r, "test", "123", iterations, wait, done) + } + + close(wait) + + for i := 0; i < numReaders+numWriters; i++ { + <-done + } + + } + +} + +func BenchmarkMutexSameReadWrite1(b *testing.B) { + benchmarkMutex(b, 1, 1, 32) +} +func BenchmarkMutexSameReadWrite2(b *testing.B) { + benchmarkMutex(b, 2, 2, 32) +} +func BenchmarkMutexSameReadWrite4(b *testing.B) { + benchmarkMutex(b, 4, 4, 32) +} +func BenchmarkMutex1(b *testing.B) { + benchmarkMutex(b, 2, 8, 32) +} +func BenchmarkMutex2(b *testing.B) { + benchmarkMutex(b, 16, 4, 64) +} +func BenchmarkMutex3(b *testing.B) { + benchmarkMutex(b, 1, 2, 128) +} +func BenchmarkMutex4(b *testing.B) { + benchmarkMutex(b, 128, 32, 256) +} +func BenchmarkMutex5(b *testing.B) { + benchmarkMutex(b, 1024, 2048, 64) +} +func BenchmarkMutex6(b *testing.B) { + benchmarkMutex(b, 2048, 1024, 512) +} diff --git a/doc.go b/doc.go new file mode 100644 index 000000000..73c740031 --- /dev/null +++ b/doc.go @@ -0,0 +1,82 @@ +// 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 context stores values shared during a request lifetime. + +For example, a router can set variables extracted from the URL and later +application handlers can access those values, or it can be used to store +sessions values to be saved at the end of a request. There are several +others common uses. + +The idea was posted by Brad Fitzpatrick to the go-nuts mailing list: + + http://groups.google.com/group/golang-nuts/msg/e2d679d303aa5d53 + +Here's the basic usage: first define the keys that you will need. The key +type is interface{} so a key can be of any type that supports equality. +Here we define a key using a custom int type to avoid name collisions: + + package foo + + import ( + "github.com/gorilla/context" + ) + + type key int + + const MyKey key = 0 + +Then set a variable. Variables are bound to an http.Request object, so you +need a request instance to set a value: + + context.Set(r, MyKey, "bar") + +The application can later access the variable using the same key you provided: + + func MyHandler(w http.ResponseWriter, r *http.Request) { + // val is "bar". + val := context.Get(r, foo.MyKey) + + // returns ("bar", true) + val, ok := context.GetOk(r, foo.MyKey) + // ... + } + +And that's all about the basic usage. We discuss some other ideas below. + +Any type can be stored in the context. To enforce a given type, make the key +private and wrap Get() and Set() to accept and return values of a specific +type: + + type key int + + const mykey key = 0 + + // GetMyKey returns a value for this package from the request values. + func GetMyKey(r *http.Request) SomeType { + if rv := context.Get(r, mykey); rv != nil { + return rv.(SomeType) + } + return nil + } + + // SetMyKey sets a value for this package in the request values. + func SetMyKey(r *http.Request, val SomeType) { + context.Set(r, mykey, val) + } + +Variables must be cleared at the end of a request, to remove all values +that were stored. This can be done in an http.Handler, after a request was +served. Just call Clear() passing the request: + + context.Clear(r) + +...or use ClearHandler(), which conveniently wraps an http.Handler to clear +variables at the end of a request lifetime. + +The Routers from the packages gorilla/mux and gorilla/pat call Clear() +so if you are using either of them you don't need to clear the context manually. +*/ +package context