Merge pull request #136 from ant0ine/ifMiddleware

implementation of the IfMiddleware

rest/if.go

@@ -0,0 +1,53 @@
+package rest
+
+import (
+	"log"
+)
+
+// IfMiddleware evaluates at runtime a condition based on the current request, and decides to
+// execute one of the other Middleware based on this boolean.
+type IfMiddleware struct {
+
+	// Runtime condition that decides of the execution of IfTrue of IfFalse.
+	Condition func(r *Request) bool
+
+	// Middleware to run when the condition is true. Note that the middleware is initialized
+	// weather if will be used or not. (Optional, pass-through if not set)
+	IfTrue Middleware
+
+	// Middleware to run when the condition is false. Note that the middleware is initialized
+	// weather if will be used or not. (Optional, pass-through if not set)
+	IfFalse Middleware
+}
+
+// MiddlewareFunc makes TimerMiddleware implement the Middleware interface.
+func (mw *IfMiddleware) MiddlewareFunc(h HandlerFunc) HandlerFunc {
+
+	if mw.Condition == nil {
+		log.Fatal("IfMiddleware Condition is required")
+	}
+
+	var ifTrueHandler HandlerFunc
+	if mw.IfTrue != nil {
+		ifTrueHandler = mw.IfTrue.MiddlewareFunc(h)
+	} else {
+		ifTrueHandler = h
+	}
+
+	var ifFalseHandler HandlerFunc
+	if mw.IfFalse != nil {
+		ifFalseHandler = mw.IfFalse.MiddlewareFunc(h)
+	} else {
+		ifFalseHandler = h
+	}
+
+	return func(w ResponseWriter, r *Request) {
+
+		if mw.Condition(r) {
+			ifTrueHandler(w, r)
+		} else {
+			ifFalseHandler(w, r)
+		}
+
+	}
+}

rest/if_test.go

@@ -0,0 +1,51 @@
+package rest
+
+import (
+	"github.com/ant0ine/go-json-rest/rest/test"
+	"testing"
+)
+
+func TestIfMiddleware(t *testing.T) {
+
+	api := NewApi()
+
+	// the middleware to test
+	api.Use(&IfMiddleware{
+		Condition: func(r *Request) bool {
+			if r.URL.Path == "/true" {
+				return true
+			}
+			return false
+		},
+		IfTrue: MiddlewareSimple(func(handler HandlerFunc) HandlerFunc {
+			return func(w ResponseWriter, r *Request) {
+				r.Env["TRUE_MIDDLEWARE"] = true
+				handler(w, r)
+			}
+		}),
+		IfFalse: MiddlewareSimple(func(handler HandlerFunc) HandlerFunc {
+			return func(w ResponseWriter, r *Request) {
+				r.Env["FALSE_MIDDLEWARE"] = true
+				handler(w, r)
+			}
+		}),
+	})
+
+	// a simple app
+	api.SetApp(AppSimple(func(w ResponseWriter, r *Request) {
+		w.WriteJson(r.Env)
+	}))
+
+	// wrap all
+	handler := api.MakeHandler()
+
+	recorded := test.RunRequest(t, handler, test.MakeSimpleRequest("GET", "http://localhost/", nil))
+	recorded.CodeIs(200)
+	recorded.ContentTypeIsJson()
+	recorded.BodyIs("{\"FALSE_MIDDLEWARE\":true}")
+
+	recorded = test.RunRequest(t, handler, test.MakeSimpleRequest("GET", "http://localhost/true", nil))
+	recorded.CodeIs(200)
+	recorded.ContentTypeIsJson()
+	recorded.BodyIs("{\"TRUE_MIDDLEWARE\":true}")
+}