Add windows support for minhttp library

pkg/minhttp/http_nix.go

@@ -1,3 +1,5 @@
+// +build linux darwin freebsd openbsd netbsd dragonfly
+
 /*
  * Minio Cloud Storage, (C) 2015 Minio, Inc.
  *
@@ -89,7 +91,7 @@ func (a *app) wait() {
 // trapSignal wait on listed signals for pre-defined behaviors
 func (a *app) trapSignal(wg *sync.WaitGroup) {
 	ch := make(chan os.Signal, 10)
-	signal.Notify(ch, syscall.SIGTERM, syscall.SIGUSR2, syscall.SIGHUP)
+	signal.Notify(ch, syscall.SIGTERM, syscall.SIGHUP)
 	for {
 		sig := <-ch
 		switch sig {
@@ -106,8 +108,6 @@ func (a *app) trapSignal(wg *sync.WaitGroup) {
 				}(s)
 			}
 			return
-		case syscall.SIGUSR2:
-			fallthrough
 		case syscall.SIGHUP:
 			// we only return here if there's an error, otherwise the new process
 			// will send us a TERM when it's ready to trigger the actual shutdown.

pkg/minhttp/http_windows.go

@@ -0,0 +1,214 @@
+// +build windows
+
+/*
+ * Minio Cloud Storage, (C) 2015 Minio, Inc.
+ *
+ * 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.
+ */
+
+// Package minhttp provides easy to use graceful restart for a set of HTTP services
+//
+// This package is a fork from https://github.com/facebookgo/grace
+//
+// Re-licensing with Apache License 2.0, with code modifications
+package minhttp
+
+import (
+	"crypto/tls"
+	"net"
+	"net/http"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+	"time"
+
+	"github.com/facebookgo/httpdown"
+	"github.com/minio/minio/pkg/probe"
+)
+
+// An app contains one or more servers and their associated configuration.
+type app struct {
+	servers   []*http.Server
+	listeners []net.Listener
+	sds       []httpdown.Server
+	net       *minNet
+	errors    chan *probe.Error
+}
+
+// listen initailize listeners
+func (a *app) listen() *probe.Error {
+	for _, s := range a.servers {
+		l, err := a.net.Listen("tcp", s.Addr)
+		if err != nil {
+			return err.Trace()
+		}
+		if s.TLSConfig != nil {
+			l = tls.NewListener(l, s.TLSConfig)
+		}
+		a.listeners = append(a.listeners, l)
+	}
+	return nil
+}
+
+// serve start serving all listeners
+func (a *app) serve() {
+	h := &httpdown.HTTP{
+		StopTimeout: 10 * time.Second,
+		KillTimeout: 1 * time.Second,
+	}
+	for i, s := range a.servers {
+		a.sds = append(a.sds, h.Serve(s, a.listeners[i]))
+	}
+}
+
+// wait for http server to signal all requests that have been served
+func (a *app) wait() {
+	var wg sync.WaitGroup
+	wg.Add(len(a.sds) * 2) // Wait & Stop
+	go a.trapSignal(&wg)
+	for _, s := range a.sds {
+		go func(s httpdown.Server) {
+			defer wg.Done()
+			if err := s.Wait(); err != nil {
+				a.errors <- probe.NewError(err)
+			}
+		}(s)
+	}
+	wg.Wait()
+}
+
+// trapSignal wait on listed signals for pre-defined behaviors
+func (a *app) trapSignal(wg *sync.WaitGroup) {
+	ch := make(chan os.Signal, 10)
+	signal.Notify(ch, syscall.SIGTERM, syscall.SIGHUP)
+	for {
+		sig := <-ch
+		switch sig {
+		case syscall.SIGTERM:
+			// this ensures a subsequent TERM will trigger standard go behaviour of terminating
+			signal.Stop(ch)
+			// roll through all initialized http servers and stop them
+			for _, s := range a.sds {
+				go func(s httpdown.Server) {
+					defer wg.Done()
+					if err := s.Stop(); err != nil {
+						a.errors <- probe.NewError(err)
+					}
+				}(s)
+			}
+			return
+		case syscall.SIGHUP:
+			// we only return here if there's an error, otherwise the new process
+			// will send us a TERM when it's ready to trigger the actual shutdown.
+			if _, err := a.net.StartProcess(); err != nil {
+				a.errors <- err.Trace()
+			}
+		}
+	}
+}
+
+// ListenAndServe will serve the given http.Servers and will monitor for signals
+// allowing for graceful termination (SIGTERM) or restart (SIGUSR2/SIGHUP).
+func ListenAndServe(servers ...*http.Server) *probe.Error {
+	// get parent process id
+	ppid := os.Getppid()
+
+	a := &app{
+		servers:   servers,
+		listeners: make([]net.Listener, 0, len(servers)),
+		sds:       make([]httpdown.Server, 0, len(servers)),
+		net:       &minNet{},
+		errors:    make(chan *probe.Error, 1+(len(servers)*2)),
+	}
+
+	// Acquire Listeners
+	if err := a.listen(); err != nil {
+		return err.Trace()
+	}
+
+	// Start serving.
+	a.serve()
+
+	// Close the parent if we inherited and it wasn't init that started us.
+	if os.Getenv("LISTEN_FDS") != "" && ppid != 1 {
+		if err := terminateProcess(ppid, 1); err != nil {
+			return probe.NewError(err)
+		}
+	}
+
+	waitdone := make(chan struct{})
+	go func() {
+		defer close(waitdone)
+		a.wait()
+		// communicate by sending not by closing a channel
+		waitdone <- struct{}{}
+	}()
+
+	select {
+	case err := <-a.errors:
+		if err == nil {
+			panic("unexpected nil error")
+		}
+		return err.Trace()
+	case <-waitdone:
+		return nil
+	}
+}
+
+// ListenAndServeLimited is similar to ListenAndServe but ratelimited with connLimit value
+func ListenAndServeLimited(connLimit int, servers ...*http.Server) *probe.Error {
+	// get parent process id
+	ppid := os.Getppid()
+
+	a := &app{
+		servers:   servers,
+		listeners: make([]net.Listener, 0, len(servers)),
+		sds:       make([]httpdown.Server, 0, len(servers)),
+		net:       &minNet{connLimit: connLimit},
+		errors:    make(chan *probe.Error, 1+(len(servers)*2)),
+	}
+
+	// Acquire Listeners
+	if err := a.listen(); err != nil {
+		return err.Trace()
+	}
+
+	// Start serving.
+	a.serve()
+
+	// Close the parent if we inherited and it wasn't init that started us.
+	if os.Getenv("LISTEN_FDS") != "" && ppid != 1 {
+		if err := terminateProcess(ppid, 1); err != nil {
+			return probe.NewError(err)
+		}
+	}
+
+	waitdone := make(chan struct{})
+	go func() {
+		defer close(waitdone)
+		a.wait()
+		// communicate by sending not by closing a channel
+		waitdone <- struct{}{}
+	}()
+
+	select {
+	case err := <-a.errors:
+		if err == nil {
+			panic("unexpected nil error")
+		}
+		return err.Trace()
+	case <-waitdone:
+		return nil
+	}
+}

pkg/minhttp/kill_windows.go

@@ -0,0 +1,34 @@
+// !build windows
+
+/*
+ * Minio Cloud Storage, (C) 2015 Minio, Inc.
+ *
+ * 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.
+ */
+
+package minhttp
+
+import (
+	"os"
+	"syscall"
+)
+
+func terminateProcess(pid, exitcode int) error {
+	h, e := syscall.OpenProcess(syscall.PROCESS_TERMINATE, false, uint32(pid))
+	if e != nil {
+		return os.NewSyscallError("OpenProcess", e)
+	}
+	defer syscall.CloseHandle(h)
+	e = syscall.TerminateProcess(h, uint32(exitcode))
+	return os.NewSyscallError("TerminateProcess", e)
+}