Merge pull request #503 from jonpulsifer/hello-404-server

 Welcome defaultbackend to the ingress-gce repo

Dockerfile.404-server

@@ -0,0 +1,22 @@
+# Copyright 2015 The Kubernetes Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+FROM scratch
+
+ADD bin/ARG_ARCH/ARG_BIN /ARG_BIN
+
+# nobody:nobody
+USER 65534:65534
+
+ENTRYPOINT ["/ARG_BIN"]

Makefile

@@ -22,6 +22,7 @@ PKG := k8s.io/ingress-gce
 # List of binaries to build. You must have a matching Dockerfile.BINARY
 # for each BINARY.
 CONTAINER_BINARIES ?= \
+	404-server \
 	e2e-test \
 	echo \
 	fuzzer \

cmd/404-server/README.md

@@ -0,0 +1,6 @@
+# 404-server (default backend)
+
+404-server is a simple webserver that satisfies the ingress, which means it has to do two things:
+
+ 1. Serves a 404 page at `/`
+ 2. Serves a 200 at `/healthz`

cmd/404-server/server.go

@@ -0,0 +1,97 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// A webserver that only serves a 404 page. Used as a default backend.
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+)
+
+func main() {
+	// command line arguments
+	port := flag.Int("port", 8080, "Port number to serve default backend 404 page.")
+	timeout := flag.Duration("timeout", 5*time.Second, "Time in seconds to wait before forcefully terminating the server.")
+
+	flag.Parse()
+
+	notFound := newHTTPServer(fmt.Sprintf(":%d", *port), notFound())
+
+	// start the main http server
+	go func() {
+		err := notFound.ListenAndServe()
+		if err != http.ErrServerClosed {
+			fmt.Fprintf(os.Stderr, "could not start http server: %s\n", err)
+			os.Exit(1)
+		}
+	}()
+
+	waitShutdown(notFound, *timeout)
+}
+
+type server struct {
+	mux *http.ServeMux
+}
+
+func (s *server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	s.mux.ServeHTTP(w, r)
+}
+
+func newHTTPServer(addr string, handler http.Handler) *http.Server {
+	return &http.Server{
+		Addr:              addr,
+		Handler:           handler,
+		ReadTimeout:       10 * time.Second,
+		ReadHeaderTimeout: 10 * time.Second,
+		WriteTimeout:      10 * time.Second,
+		IdleTimeout:       10 * time.Second,
+	}
+}
+
+func notFound(options ...func(*server)) *server {
+	s := &server{mux: http.NewServeMux()}
+	// TODO: this handler exists only to avoid breaking existing deployments
+	s.mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		fmt.Fprint(w, "ok")
+	})
+	s.mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		fmt.Fprint(w, "default backend - 404")
+	})
+	return s
+}
+
+func waitShutdown(s *http.Server, timeout time.Duration) {
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, os.Interrupt, syscall.SIGTERM)
+	<-stop
+
+	fmt.Fprintf(os.Stdout, "stopping http server...\n")
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	if err := s.Shutdown(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "could not gracefully shutdown http server: %s\n", err)
+	}
+}