Drop context arg from HTTP handler (#58)

* drop context arg from HTTP handler

* fix data races

cloudevents/service.go

@@ -60,7 +60,7 @@ func New(f any) *Service {
 	mux.HandleFunc("/health/readiness", svc.Ready)
 	mux.HandleFunc("/health/liveness", svc.Alive)
 	mux.Handle("/", newCloudeventHandler(f)) // See implementation note
-	svc.Server.Handler = mux
+	svc.Handler = mux
 	return svc
 }
 
@@ -91,7 +91,7 @@ func (s *Service) Start(ctx context.Context) (err error) {
 	s.handleSignals()
 
 	go func() {
-		if err = s.Server.Serve(s.listener); err != http.ErrServerClosed {
+		if err := s.Serve(s.listener); err != http.ErrServerClosed {
 			log.Error().Err(err).Msg("http server exited with unexpected error")
 			s.stop <- err
 		}

cmd/fhttp/main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"context"
 	"fmt"
 	"net/http"
 	"os"
@@ -25,9 +24,9 @@ func main() {
 }
 
 // Example Static HTTP Handler implementation.
-func Handle(ctx context.Context, res http.ResponseWriter, req *http.Request) {
+func Handle(w http.ResponseWriter, r *http.Request) {
 	fmt.Println("Static HTTP handler invoked")
-	res.Write([]byte("Static HTTP handler invoked\n"))
+	fmt.Fprintln(w, "Static HTTP Handler invoked")
 }
 
 // MyFunction is an example instanced HTTP function implementation.
@@ -37,7 +36,7 @@ func New() *MyFunction {
 	return &MyFunction{}
 }
 
-func (f *MyFunction) Handle(_ context.Context, res http.ResponseWriter, req *http.Request) {
+func (f *MyFunction) Handle(w http.ResponseWriter, r *http.Request) {
 	fmt.Println("Instanced HTTP handler invoked")
-	res.Write([]byte("Instanced HTTP handler invoked\n"))
+	fmt.Fprintln(w, "Instanced HTTP Handler invoked")
 }

http/instance.go

@@ -3,8 +3,6 @@ package http
 import (
 	"context"
 	"net/http"
-
-	"github.com/rs/zerolog/log"
 )
 
 // Handler is a function instance which can handle a request.
@@ -14,9 +12,11 @@ import (
 // framework is the same.
 type Handler interface {
 	// Handle a request.
-	Handle(context.Context, http.ResponseWriter, *http.Request)
+	Handle(http.ResponseWriter, *http.Request)
 }
 
+type HandleFunc func(http.ResponseWriter, *http.Request)
+
 // Starter is an instance which has defined the Start hook
 type Starter interface {
 	// Start instance event hook.
@@ -41,26 +41,12 @@ type LivenessReporter interface {
 	Alive(context.Context) (bool, error)
 }
 
-// HandleFunc defines the function signature expected of static Functions.
-type HandleFunc func(context.Context, http.ResponseWriter, *http.Request)
-
 // DefaultHandler is used for simple static function implementations which
 // need only define a single exported function named Handle of type HandleFunc.
 type DefaultHandler struct {
 	Handler HandleFunc
 }
 
-// Handle a request by passing to the handler function.
-func (f DefaultHandler) Handle(ctx context.Context, res http.ResponseWriter, req *http.Request) {
-	if f.Handler == nil {
-		f.Handler = defaultHandler
-	}
-	f.Handler(ctx, res, req)
-}
-
-// DefaultHandler is a Handler implementation which simply warns the user that
-// the default handler instance was not properly initialized.
-var defaultHandler = func(_ context.Context, res http.ResponseWriter, req *http.Request) {
-	log.Warn().Msg("no Handle method found")
-	http.NotFound(res, req)
+func (f DefaultHandler) Handle(w http.ResponseWriter, r *http.Request) {
+	f.Handler(w, r)
 }

http/mock/function.go

@@ -8,7 +8,7 @@ import (
 type Function struct {
 	OnStart  func(context.Context, map[string]string) error
 	OnStop   func(context.Context) error
-	OnHandle func(context.Context, http.ResponseWriter, *http.Request)
+	OnHandle func(http.ResponseWriter, *http.Request)
 }
 
 func (f *Function) Start(ctx context.Context, cfg map[string]string) error {
@@ -25,8 +25,8 @@ func (f *Function) Stop(ctx context.Context) error {
 	return nil
 }
 
-func (f *Function) Handle(ctx context.Context, w http.ResponseWriter, r *http.Request) {
+func (f *Function) Handle(w http.ResponseWriter, r *http.Request) {
 	if f.OnHandle != nil {
-		f.OnHandle(ctx, w, r)
+		f.OnHandle(w, r)
 	}
 }

http/service.go

@@ -32,7 +32,7 @@ const (
 // Start an intance using a new Service
 // Note that for CloudEvent Handlers this effectively accepts ANY because
 // the actual type of the handler function is determined later.
-func Start(f any) error {
+func Start(f Handler) error {
 	log.Debug().Msg("func runtime creating function instance")
 	return New(f).Start(context.Background())
 }
@@ -42,11 +42,11 @@ type Service struct {
 	http.Server
 	listener net.Listener
 	stop     chan error
-	f        any
+	f        Handler
 }
 
 // New Service which serves the given instance.
-func New(f any) *Service {
+func New(f Handler) *Service {
 	svc := &Service{
 		f:    f,
 		stop: make(chan error),
@@ -62,7 +62,7 @@ func New(f any) *Service {
 	mux.HandleFunc("/health/readiness", svc.Ready)
 	mux.HandleFunc("/health/liveness", svc.Alive)
 	mux.HandleFunc("/", svc.Handle)
-	svc.Server.Handler = mux
+	svc.Handler = mux
 
 	// Print some helpful information about which interfaces the function
 	// is correctly implementing
@@ -74,9 +74,6 @@ func New(f any) *Service {
 // log which interfaces the function implements.
 // This could be more verbose for new users:
 func logImplements(f any) {
-	if _, ok := f.(Handler); ok {
-		log.Info().Msg("Function implements Handle")
-	}
 	if _, ok := f.(Starter); ok {
 		log.Info().Msg("Function implements Start")
 	}
@@ -123,7 +120,7 @@ func (s *Service) Start(ctx context.Context) (err error) {
 
 	// Listen and serve
 	go func() {
-		if err = s.Server.Serve(s.listener); err != http.ErrServerClosed {
+		if err := s.Serve(s.listener); err != http.ErrServerClosed {
 			log.Error().Err(err).Msg("http server exited with unexpected error")
 			s.stop <- err
 		}
@@ -180,13 +177,7 @@ func (s *Service) Addr() net.Addr {
 
 // Handle requests for the instance
 func (s *Service) Handle(w http.ResponseWriter, r *http.Request) {
-	if i, ok := s.f.(Handler); ok {
-		i.Handle(r.Context(), w, r)
-	} else {
-		message := "function does not implement Handle. Skipping invocation."
-		log.Debug().Msg(message)
-		_, _ = w.Write([]byte(message))
-	}
+	s.f.Handle(w, r)
 }
 
 // Ready handles readiness checks.
@@ -197,11 +188,11 @@ func (s *Service) Ready(w http.ResponseWriter, r *http.Request) {
 			message := "error checking readiness"
 			log.Debug().Err(err).Msg(message)
 			w.WriteHeader(500)
-			_, _ = w.Write([]byte(message + ". " + err.Error()))
+			fmt.Fprint(w, "error checking readiness: ", err.Error())
 			return
 		}
 		if !ready {
-			message := "function not yet available"
+			message := "function not yet ready"
 			log.Debug().Msg(message)
 			w.WriteHeader(503)
 			fmt.Fprintln(w, message)
@@ -219,11 +210,11 @@ func (s *Service) Alive(w http.ResponseWriter, r *http.Request) {
 			message := "error checking liveness"
 			log.Err(err).Msg(message)
 			w.WriteHeader(500)
-			_, _ = w.Write([]byte(message + ". " + err.Error()))
+			fmt.Fprint(w, "error checking liveness: ", err.Error())
 			return
 		}
 		if !alive {
-			message := "function not ready"
+			message := "function not alive"
 			log.Debug().Msg(message)
 			w.WriteHeader(503)
 			_, _ = w.Write([]byte(message))

http/service_test.go

@@ -257,7 +257,7 @@ func TestHandle_Invoked(t *testing.T) {
 			startCh <- true
 			return nil
 		}
-		onHandle = func(_ context.Context, w http.ResponseWriter, _ *http.Request) {
+		onHandle = func(w http.ResponseWriter, _ *http.Request) {
 			fmt.Fprintf(w, "OK")
 		}
 	)
@@ -358,7 +358,7 @@ func TestAlive_Invoked(t *testing.T) {
 		errCh       = make(chan error)
 		startCh     = make(chan any)
 		timeoutCh   = time.After(500 * time.Millisecond)
-		onStart     = func(_ context.Context, _ map[string]string) error {
+		onStart     = func(context.Context, map[string]string) error {
 			startCh <- true
 			return nil
 		}