httphelper: add more helpers for Handler w/ context

bgentry · bgentry · commit a64d89a97513 · 2015-01-29T21:22:13.000-08:00
Add an httphelper.Handler type that is analogous to the http.Handler
type, except that it also takes a context.

Also fix WrapHandler so that it calls ServeHTTP on the HandlerFunc.

Signed-off-by: Blake Gentry &lt;blakesgentry@gmail.com&gt;
diff --git a/pkg/httphelper/httphelper.go b/pkg/httphelper/httphelper.go
@@ -50,13 +50,27 @@ var CORSAllowAllHandler = cors.Allow(&cors.Options{
 	MaxAge:           time.Hour,
 })
 
+// Handler is an extended version of http.Handler that also takes a context
+// argument ctx.
+type Handler interface {
+	ServeHTTP(ctx context.Context, w http.ResponseWriter, r *http.Request)
+}
+
+// The HandlerFunc type is an adapter to allow the use of ordinary functions as
+// Handlers.  If f is a function with the appropriate signature, HandlerFunc(f)
+// is a Handler object that calls f.
 type HandlerFunc func(context.Context, http.ResponseWriter, *http.Request)
 
+// ServeHTTP calls f(ctx, w, r).
+func (f HandlerFunc) ServeHTTP(ctx context.Context, w http.ResponseWriter, r *http.Request) {
+	f(ctx, w, r)
+}
+
 func WrapHandler(handler HandlerFunc) httprouter.Handle {
 	return func(w http.ResponseWriter, req *http.Request, params httprouter.Params) {
 		ctx := contextFromResponseWriter(w)
 		ctx = ctxhelper.NewContextParams(ctx, params)
-		handler(ctx, w, req)
+		handler.ServeHTTP(ctx, w, req)
 	}
 }
 
