Stop setting a 'Content-Type' header for custom HTTP handlers

hoisie · hoisie · commit c21e884130c4 · 2016-07-30T20:55:08.000-07:00
Previously, when using web.Handle, the `Content-Type` HTTP header was set by default to `text/html; charset=utf-8`. This does not play nicely well with Go's FileHandler. If a `Content-Type` header is set, Go's FileHandler will not overwrite it. This breaks serving static assets with a FileHandler. This resolves hoisie#158
diff --git a/server.go b/server.go
@@ -335,9 +335,6 @@ func (s *Server) routeHandler(req *http.Request, w http.ResponseWriter) (unused
 		}
 	}
 
-	//Set the default content-type
-	ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)
-
 	for i := 0; i < len(s.routes); i++ {
 		route := s.routes[i]
 		cr := route.cr
@@ -361,6 +358,9 @@ func (s *Server) routeHandler(req *http.Request, w http.ResponseWriter) (unused
 			return
 		}
 
+		// set the default content-type
+		ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)
+
 		var args []reflect.Value
 		handlerType := route.handler.Type()
 		if requiresContext(handlerType) {
diff --git a/web.go b/web.go
@@ -43,6 +43,7 @@ func (ctx *Context) WriteString(content string) {
 // Once it has been called, any return value from the handler will
 // not be written to the response.
 func (ctx *Context) Abort(status int, body string) {
+	ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)
 	ctx.ResponseWriter.WriteHeader(status)
 	ctx.ResponseWriter.Write([]byte(body))
 }
@@ -250,7 +251,7 @@ func Match(method string, route string, handler interface{}) {
 	mainServer.addRoute(route, method, handler)
 }
 
-// Add a custom HTTP handler for a path. This will have no effect when running as FCGI or SCGI.
+// Add a custom http.Handler. Will have no effect when running as FCGI or SCGI.
 func Handle(route string, method string, httpHandler http.Handler) {
 	mainServer.Handle(route, method, httpHandler)
 }
diff --git a/web_test.go b/web_test.go
@@ -591,6 +591,24 @@ func TestNoColorOutput(t *testing.T) {
 	}
 }
 
+type TestHandler struct{}
+
+func (t *TestHandler) ServeHTTP(c http.ResponseWriter, req *http.Request) {
+}
+
+// When a custom HTTP handler is used, the Content-Type header should not be set to a default.
+// Go's FileHandler does not replace the Content-Type header if it is already set.
+func TestCustomHandlerContentType(t *testing.T) {
+	s := NewServer()
+	s.Handle("/testHandler", "GET", &TestHandler{})
+	req := buildTestRequest("GET", "/testHandler", "", nil, nil)
+	c := scgiConn{wroteHeaders: false, req: req, headers: make(map[string][]string), fd: nil}
+	s.Process(&c, req)
+	if c.headers["Content-Type"] != nil {
+		t.Fatalf("A default Content-Type should not be present when using a custom HTTP handler")
+	}
+}
+
 func BuildBasicAuthCredentials(user string, pass string) string {
 	s := user + ":" + pass
 	return "Basic " + base64.StdEncoding.EncodeToString([]byte(s))

Original file line number	Diff line number	Diff line change
`@@ -335,9 +335,6 @@ func (s Server) routeHandler(req http.Request, w http.ResponseWriter) (unused`
`335`	`335`	`}`
`336`	`336`	`}`
`337`	`337`
`338`		`- //Set the default content-type`
`339`		`- ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)`
`340`		`-`
`341`	`338`	`for i := 0; i < len(s.routes); i++ {`
`342`	`339`	`route := s.routes[i]`
`343`	`340`	`cr := route.cr`
`@@ -361,6 +358,9 @@ func (s Server) routeHandler(req http.Request, w http.ResponseWriter) (unused`
`361`	`358`	`return`
`362`	`359`	`}`
`363`	`360`
	`361`	`+ // set the default content-type`
	`362`	`+ ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)`
	`363`	`+`
`364`	`364`	`var args []reflect.Value`
`365`	`365`	`handlerType := route.handler.Type()`
`366`	`366`	`if requiresContext(handlerType) {`
Original file line number	Diff line number	Diff line change
`@@ -43,6 +43,7 @@ func (ctx *Context) WriteString(content string) {`
`43`	`43`	`// Once it has been called, any return value from the handler will`
`44`	`44`	`// not be written to the response.`
`45`	`45`	`func (ctx *Context) Abort(status int, body string) {`
	`46`	`+ ctx.SetHeader("Content-Type", "text/html; charset=utf-8", true)`
`46`	`47`	`ctx.ResponseWriter.WriteHeader(status)`
`47`	`48`	`ctx.ResponseWriter.Write([]byte(body))`
`48`	`49`	`}`
`@@ -250,7 +251,7 @@ func Match(method string, route string, handler interface{}) {`
`250`	`251`	`mainServer.addRoute(route, method, handler)`
`251`	`252`	`}`
`252`	`253`
`253`		`-// Add a custom HTTP handler for a path. This will have no effect when running as FCGI or SCGI.`
	`254`	`+// Add a custom http.Handler. Will have no effect when running as FCGI or SCGI.`
`254`	`255`	`func Handle(route string, method string, httpHandler http.Handler) {`
`255`	`256`	`mainServer.Handle(route, method, httpHandler)`
`256`	`257`	`}`