From 930b639cc9cd2d2873302f30303378c0e53816a8 Mon Sep 17 00:00:00 2001 From: Wim Date: Sat, 18 Feb 2017 23:00:46 +0100 Subject: Update vendor --- .../github.com/facebookgo/grace/gracehttp/http.go | 190 +++++++++++++++++++++ .../github.com/facebookgo/grace/gracehttp/license | 30 ++++ 2 files changed, 220 insertions(+) create mode 100644 vendor/github.com/facebookgo/grace/gracehttp/http.go create mode 100644 vendor/github.com/facebookgo/grace/gracehttp/license (limited to 'vendor/github.com/facebookgo/grace/gracehttp') diff --git a/vendor/github.com/facebookgo/grace/gracehttp/http.go b/vendor/github.com/facebookgo/grace/gracehttp/http.go new file mode 100644 index 00000000..fa3ac883 --- /dev/null +++ b/vendor/github.com/facebookgo/grace/gracehttp/http.go @@ -0,0 +1,190 @@ +// Package gracehttp provides easy to use graceful restart +// functionality for HTTP server. +package gracehttp + +import ( + "bytes" + "crypto/tls" + "fmt" + "log" + "net" + "net/http" + "os" + "os/signal" + "sync" + "syscall" + + "github.com/facebookgo/grace/gracenet" + "github.com/facebookgo/httpdown" +) + +var ( + logger *log.Logger + didInherit = os.Getenv("LISTEN_FDS") != "" + ppid = os.Getppid() +) + +// An app contains one or more servers and associated configuration. +type app struct { + servers []*http.Server + http *httpdown.HTTP + net *gracenet.Net + listeners []net.Listener + sds []httpdown.Server + errors chan error +} + +func newApp(servers []*http.Server) *app { + return &app{ + servers: servers, + http: &httpdown.HTTP{}, + net: &gracenet.Net{}, + listeners: make([]net.Listener, 0, len(servers)), + sds: make([]httpdown.Server, 0, len(servers)), + + // 2x num servers for possible Close or Stop errors + 1 for possible + // StartProcess error. + errors: make(chan error, 1+(len(servers)*2)), + } +} + +func (a *app) listen() error { + for _, s := range a.servers { + // TODO: default addresses + l, err := a.net.Listen("tcp", s.Addr) + if err != nil { + return err + } + if s.TLSConfig != nil { + l = tls.NewListener(l, s.TLSConfig) + } + a.listeners = append(a.listeners, l) + } + return nil +} + +func (a *app) serve() { + for i, s := range a.servers { + a.sds = append(a.sds, a.http.Serve(s, a.listeners[i])) + } +} + +func (a *app) wait() { + var wg sync.WaitGroup + wg.Add(len(a.sds) * 2) // Wait & Stop + go a.signalHandler(&wg) + for _, s := range a.sds { + go func(s httpdown.Server) { + defer wg.Done() + if err := s.Wait(); err != nil { + a.errors <- err + } + }(s) + } + wg.Wait() +} + +func (a *app) term(wg *sync.WaitGroup) { + for _, s := range a.sds { + go func(s httpdown.Server) { + defer wg.Done() + if err := s.Stop(); err != nil { + a.errors <- err + } + }(s) + } +} + +func (a *app) signalHandler(wg *sync.WaitGroup) { + ch := make(chan os.Signal, 10) + signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM, syscall.SIGUSR2) + for { + sig := <-ch + switch sig { + case syscall.SIGINT, syscall.SIGTERM: + // this ensures a subsequent INT/TERM will trigger standard go behaviour of + // terminating. + signal.Stop(ch) + a.term(wg) + return + case syscall.SIGUSR2: + // 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 + } + } + } +} + +// Serve will serve the given http.Servers and will monitor for signals +// allowing for graceful termination (SIGTERM) or restart (SIGUSR2). +func Serve(servers ...*http.Server) error { + a := newApp(servers) + + // Acquire Listeners + if err := a.listen(); err != nil { + return err + } + + // Some useful logging. + if logger != nil { + if didInherit { + if ppid == 1 { + logger.Printf("Listening on init activated %s", pprintAddr(a.listeners)) + } else { + const msg = "Graceful handoff of %s with new pid %d and old pid %d" + logger.Printf(msg, pprintAddr(a.listeners), os.Getpid(), ppid) + } + } else { + const msg = "Serving %s with pid %d" + logger.Printf(msg, pprintAddr(a.listeners), os.Getpid()) + } + } + + // Start serving. + a.serve() + + // Close the parent if we inherited and it wasn't init that started us. + if didInherit && ppid != 1 { + if err := syscall.Kill(ppid, syscall.SIGTERM); err != nil { + return fmt.Errorf("failed to close parent: %s", err) + } + } + + waitdone := make(chan struct{}) + go func() { + defer close(waitdone) + a.wait() + }() + + select { + case err := <-a.errors: + if err == nil { + panic("unexpected nil error") + } + return err + case <-waitdone: + if logger != nil { + logger.Printf("Exiting pid %d.", os.Getpid()) + } + return nil + } +} + +// Used for pretty printing addresses. +func pprintAddr(listeners []net.Listener) []byte { + var out bytes.Buffer + for i, l := range listeners { + if i != 0 { + fmt.Fprint(&out, ", ") + } + fmt.Fprint(&out, l.Addr()) + } + return out.Bytes() +} + +// SetLogger sets logger to be able to grab some useful logs +func SetLogger(l *log.Logger) { + logger = l +} diff --git a/vendor/github.com/facebookgo/grace/gracehttp/license b/vendor/github.com/facebookgo/grace/gracehttp/license new file mode 100644 index 00000000..3aea8753 --- /dev/null +++ b/vendor/github.com/facebookgo/grace/gracehttp/license @@ -0,0 +1,30 @@ +BSD License + +For grace software + +Copyright (c) 2015, Facebook, Inc. All rights reserved. + +Redistribution and use in source and binary forms, with or without modification, +are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, this + list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above copyright notice, + this list of conditions and the following disclaimer in the documentation + and/or other materials provided with the distribution. + + * Neither the name Facebook nor the names of its contributors may be used to + endorse or promote products derived from this software without specific + prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND +ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR +ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON +ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -- cgit v1.2.3