make cache package to work across multi handlers, remove the old 'WrapHandler' and keep the cache.Handler as documented only

Former-commit-id: b030cd92d26a9f646b060e379b3702b9a677749b

cache/LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2017 The Iris Cache Authors. All rights reserved.
+Copyright (c) 2017-2018 The Iris Cache Authors. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are

cache/cache.go

@@ -7,18 +7,17 @@ Example code:
 		 	"time"
 
 		 	"github.com/kataras/iris"
-		 	"github.com/kataras/iris/context"
 		 	"github.com/kataras/iris/cache"
 		 )
 
 		 func main(){
 		 	app := iris.Default()
-		 	cachedHandler := cache.WrapHandler(h, 2 *time.Minute)
-		 	app.Get("/hello", cachedHandler)
+		 	middleware := cache.Handler(2 *time.Minute)
+		 	app.Get("/hello", middleware, h)
 		 	app.Run(iris.Addr(":8080"))
 		 }
 
-		 func h(ctx context.Context) {
+		 func h(ctx iris.Context) {
 		 	ctx.HTML("<h1> Hello, this should be cached. Every 2 minutes it will be refreshed, check your browser's inspector</h1>")
 		 }
 */
@@ -32,46 +31,29 @@ import (
 	"github.com/kataras/iris/context"
 )
 
-// Cache accepts two parameters
-// first is the context.Handler which you want to cache its result
-// the second is, optional, the cache Entry's expiration duration
+// Cache accepts the cache expiration duration
 // if the expiration <=2 seconds then expiration is taken by the "cache-control's maxage" header
 // returns context.Handler, which you can use as your default router or per-route handler
 //
 // All types of response can be cached, templates, json, text, anything.
 //
 // You can add validators with this function.
-func Cache(bodyHandler context.Handler, expiration time.Duration) *client.Handler {
-	return client.NewHandler(bodyHandler, expiration)
-}
-
-// WrapHandler accepts two parameters
-// first is the context.Handler which you want to cache its result
-// the second is, optional, the cache Entry's expiration duration
-// if the expiration <=2 seconds then expiration is taken by the "cache-control's maxage" header
-// returns context.Handler, which you can use as your default router or per-route handler
-//
-// All types of response can be cached, templates, json, text, anything.
-//
-// it returns a context.Handler, for more options use the `Cache`
-func WrapHandler(bodyHandler context.Handler, expiration time.Duration) context.Handler {
-	return Cache(bodyHandler, expiration).ServeHTTP
+func Cache(expiration time.Duration) *client.Handler {
+	return client.NewHandler(expiration)
 }
 
 // Handler accepts one single parameter:
-// the cache Entry's expiration duration
+// the cache expiration duration
 // if the expiration <=2 seconds then expiration is taken by the "cache-control's maxage" header
 // returns context.Handler.
 //
-// It's the same as Cache and WrapHandler but it sets the "bodyHandler" to the next handler in the chain.
-//
 // All types of response can be cached, templates, json, text, anything.
 //
 // it returns a context.Handler which can be used as a middleware, for more options use the `Cache`.
 //
 // Examples can be found at: https://github.com/kataras/iris/tree/master/_examples/#caching
 func Handler(expiration time.Duration) context.Handler {
-	h := WrapHandler(nil, expiration)
+	h := Cache(expiration).ServeHTTP
 	return h
 }
 

cache/cache_test.go

@@ -23,10 +23,10 @@ var (
 	errTestFailed   = errors.New("expected the main handler to be executed %d times instead of %d")
 )
 
-func runTest(e *httpexpect.Expect, counterPtr *uint32, expectedBodyStr string, nocache string) error {
-	e.GET("/").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+func runTest(e *httpexpect.Expect, path string, counterPtr *uint32, expectedBodyStr string, nocache string) error {
+	e.GET(path).Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 	time.Sleep(cacheDuration / 5) // lets wait for a while, cache should be saved and ready
-	e.GET("/").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+	e.GET(path).Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 	counter := atomic.LoadUint32(counterPtr)
 	if counter > 1 {
 		// n should be 1 because it doesn't changed after the first call
@@ -35,19 +35,19 @@ func runTest(e *httpexpect.Expect, counterPtr *uint32, expectedBodyStr string, n
 	time.Sleep(cacheDuration)
 
 	// cache should be cleared now
-	e.GET("/").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+	e.GET(path).Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 	time.Sleep(cacheDuration / 5)
 	// let's call again , the cache should be saved
-	e.GET("/").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+	e.GET(path).Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 	counter = atomic.LoadUint32(counterPtr)
 	if counter != 2 {
 		return errTestFailed.Format(2, counter)
 	}
 
-	// we have cache response saved for the "/" path, we have some time more here, but here
+	// we have cache response saved for the path, we have some time more here, but here
 	// we will make the requestS with some of the deniers options
-	e.GET("/").WithHeader("max-age", "0").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
-	e.GET("/").WithHeader("Authorization", "basic or anything").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+	e.GET(path).WithHeader("max-age", "0").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+	e.GET(path).WithHeader("Authorization", "basic or anything").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 	counter = atomic.LoadUint32(counterPtr)
 	if counter != 4 {
 		return errTestFailed.Format(4, counter)
@@ -71,8 +71,8 @@ func runTest(e *httpexpect.Expect, counterPtr *uint32, expectedBodyStr string, n
 			return errTestFailed.Format(6, counter)
 		}
 
-		// let's call again the "/", the expiration is not passed so  it should be cached
-		e.GET("/").Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
+		// let's call again the path the expiration is not passed so  it should be cached
+		e.GET(path).Expect().Status(http.StatusOK).Body().Equal(expectedBodyStr)
 		counter = atomic.LoadUint32(counterPtr)
 		if counter != 6 {
 			return errTestFailed.Format(6, counter)
@@ -88,19 +88,19 @@ func TestNoCache(t *testing.T) {
 	app := iris.New()
 	var n uint32
 
-	app.Get("/", cache.WrapHandler(func(ctx context.Context) {
+	app.Get("/", cache.Handler(cacheDuration), func(ctx context.Context) {
 		atomic.AddUint32(&n, 1)
 		ctx.Write([]byte(expectedBodyStr))
-	}, cacheDuration))
+	})
 
-	app.Get("/nocache", cache.WrapHandler(func(ctx context.Context) {
+	app.Get("/nocache", cache.Handler(cacheDuration), func(ctx context.Context) {
 		cache.NoCache(ctx) // <----
 		atomic.AddUint32(&n, 1)
 		ctx.Write([]byte(expectedBodyStr))
-	}, cacheDuration))
+	})
 
 	e := httptest.New(t, app)
-	if err := runTest(e, &n, expectedBodyStr, "/nocache"); err != nil {
+	if err := runTest(e, "/", &n, expectedBodyStr, "/nocache"); err != nil {
 		t.Fatalf(t.Name()+": %v", err)
 	}
 
@@ -117,11 +117,25 @@ func TestCache(t *testing.T) {
 		ctx.Write([]byte(expectedBodyStr))
 	})
 
+	var (
+		n2               uint32
+		expectedBodyStr2 = "This is the other"
+	)
+
+	app.Get("/other", func(ctx context.Context) {
+		atomic.AddUint32(&n2, 1)
+		ctx.Write([]byte(expectedBodyStr2))
+	})
+
 	e := httptest.New(t, app)
-	if err := runTest(e, &n, expectedBodyStr, ""); err != nil {
+	if err := runTest(e, "/", &n, expectedBodyStr, ""); err != nil {
 		t.Fatalf(t.Name()+": %v", err)
 	}
 
+	if err := runTest(e, "/other", &n2, expectedBodyStr2, ""); err != nil {
+		t.Fatalf(t.Name()+" other: %v", err)
+	}
+
 }
 
 func TestCacheHandlerParallel(t *testing.T) {
@@ -138,10 +152,10 @@ func TestCacheValidator(t *testing.T) {
 		ctx.Write([]byte(expectedBodyStr))
 	}
 
-	validCache := cache.Cache(h, cacheDuration)
-	app.Get("/", validCache.ServeHTTP)
+	validCache := cache.Cache(cacheDuration)
+	app.Get("/", validCache.ServeHTTP, h)
 
-	managedCache := cache.Cache(h, cacheDuration)
+	managedCache := cache.Cache(cacheDuration)
 	managedCache.AddRule(rule.Validator([]rule.PreValidator{
 		func(ctx context.Context) bool {
 			if ctx.Request().URL.Path == "/invalid" {
@@ -151,12 +165,7 @@ func TestCacheValidator(t *testing.T) {
 		},
 	}, nil))
 
-	managedCache2 := cache.Cache(func(ctx context.Context) {
-		atomic.AddUint32(&n, 1)
-		ctx.Header("DONT", "DO not cache that response even if it was claimed")
-		ctx.Write([]byte(expectedBodyStr))
-
-	}, cacheDuration)
+	managedCache2 := cache.Cache(cacheDuration)
 	managedCache2.AddRule(rule.Validator(nil,
 		[]rule.PostValidator{
 			func(ctx context.Context) bool {
@@ -168,10 +177,15 @@ func TestCacheValidator(t *testing.T) {
 		},
 	))
 
-	app.Get("/valid", validCache.ServeHTTP)
+	app.Get("/valid", validCache.ServeHTTP, h)
 
-	app.Get("/invalid", managedCache.ServeHTTP)
-	app.Get("/invalid2", managedCache2.ServeHTTP)
+	app.Get("/invalid", managedCache.ServeHTTP, h)
+	app.Get("/invalid2", managedCache2.ServeHTTP, func(ctx context.Context) {
+		atomic.AddUint32(&n, 1)
+		ctx.Header("DONT", "DO not cache that response even if it was claimed")
+		ctx.Write([]byte(expectedBodyStr))
+
+	})
 
 	e := httptest.New(t, app)
 

cache/client/handler.go

@@ -1,6 +1,7 @@
 package client
 
 import (
+	"sync"
 	"time"
 
 	"github.com/kataras/iris/cache/cfg"
@@ -10,34 +11,27 @@ import (
 )
 
 // Handler the local cache service handler contains
-// the original bodyHandler, the memory cache entry and
+// the original response, the memory cache entry and
 // the validator for each of the incoming requests and post responses
 type Handler struct {
-
-	// bodyHandler the original route's handler.
-	// If nil then it tries to take the next handler from the chain.
-	bodyHandler context.Handler
-
 	// Rule optional validators for pre cache and post cache actions
 	//
 	// See more at ruleset.go
 	rule rule.Rule
-
-	// entry is the memory cache entry
-	entry *entry.Entry
+	// when expires.
+	expiration time.Duration
+	// entries the memory cache stored responses.
+	entries map[string]*entry.Entry
+	mu      sync.RWMutex
 }
 
 // NewHandler returns a new cached handler for the "bodyHandler"
 // which expires every "expiration".
-func NewHandler(bodyHandler context.Handler,
-	expiration time.Duration) *Handler {
-
-	e := entry.NewEntry(expiration)
-
+func NewHandler(expiration time.Duration) *Handler {
 	return &Handler{
-		bodyHandler: bodyHandler,
-		rule:        DefaultRuleSet,
-		entry:       e,
+		rule:       DefaultRuleSet,
+		expiration: expiration,
+		entries:    make(map[string]*entry.Entry, 0),
 	}
 }
 
@@ -66,35 +60,53 @@ func (h *Handler) AddRule(r rule.Rule) *Handler {
 	return h
 }
 
+var emptyHandler = func(ctx context.Context) {
+	ctx.StatusCode(500)
+	ctx.WriteString("cache: empty body handler")
+	ctx.StopExecution()
+}
+
 func (h *Handler) ServeHTTP(ctx context.Context) {
 	// check for pre-cache validators, if at least one of them return false
 	// for this specific request, then skip the whole cache
-	bodyHandler := h.bodyHandler
-
+	bodyHandler := ctx.NextHandler()
 	if bodyHandler == nil {
-		if nextHandler := ctx.NextHandler(); nextHandler != nil {
-			// skip prepares the context to move to the next handler if the "nextHandler" has a ctx.Next() inside it,
-			// even if it's not executed because it's cached.
-			ctx.Skip()
-			bodyHandler = nextHandler
-		} else {
-			ctx.StatusCode(500)
-			ctx.WriteString("cache: empty body handler")
-			ctx.StopExecution()
-			return
-		}
+		emptyHandler(ctx)
+		return
 	}
+	// skip prepares the context to move to the next handler if the "nextHandler" has a ctx.Next() inside it,
+	// even if it's not executed because it's cached.
+	ctx.Skip()
 
 	if !h.rule.Claim(ctx) {
 		bodyHandler(ctx)
 		return
 	}
 
-	// check if we have a stored response( it is not expired)
-	res, exists := h.entry.Response()
-	if !exists {
+	var (
+		response *entry.Response
+		valid    = false
+		key      = ctx.Path()
+	)
 
-		// if it's not exists, then execute the original handler
+	h.mu.RLock()
+	e, found := h.entries[key]
+	h.mu.RUnlock()
+
+	if found {
+		// the entry is here, .Response will give us
+		// if it's expired or no
+		response, valid = e.Response()
+	} else {
+		// create the entry now.
+		e = entry.NewEntry(h.expiration)
+		h.mu.Lock()
+		h.entries[key] = e
+		h.mu.Unlock()
+	}
+
+	if !valid {
+		// if it's expired, then execute the original handler
 		// with our custom response recorder response writer
 		// because the net/http doesn't give us
 		// a built'n way to get the status code & body
@@ -119,12 +131,12 @@ func (h *Handler) ServeHTTP(ctx context.Context) {
 		// check for an expiration time if the
 		// given expiration was not valid then check for GetMaxAge &
 		// update the response & release the recorder
-		h.entry.Reset(recorder.StatusCode(), recorder.Header().Get(cfg.ContentTypeHeader), body, GetMaxAge(ctx.Request()))
+		e.Reset(recorder.StatusCode(), recorder.Header().Get(cfg.ContentTypeHeader), body, GetMaxAge(ctx.Request()))
 		return
 	}
 
 	// if it's valid then just write the cached results
-	ctx.ContentType(res.ContentType())
-	ctx.StatusCode(res.StatusCode())
-	ctx.Write(res.Body())
+	ctx.ContentType(response.ContentType())
+	ctx.StatusCode(response.StatusCode())
+	ctx.Write(response.Body())
 }