diff options
Diffstat (limited to 'vendor/github.com/facebookgo/httpdown')
| -rw-r--r-- | vendor/github.com/facebookgo/httpdown/httpdown.go | 376 | ||||
| -rw-r--r-- | vendor/github.com/facebookgo/httpdown/license | 30 | ||||
| -rw-r--r-- | vendor/github.com/facebookgo/httpdown/patents | 33 | ||||
| -rw-r--r-- | vendor/github.com/facebookgo/httpdown/readme.md | 41 |
4 files changed, 480 insertions, 0 deletions
diff --git a/vendor/github.com/facebookgo/httpdown/httpdown.go b/vendor/github.com/facebookgo/httpdown/httpdown.go new file mode 100644 index 0000000000..34c5dea9ff --- /dev/null +++ b/vendor/github.com/facebookgo/httpdown/httpdown.go @@ -0,0 +1,376 @@ +// Package httpdown provides http.ConnState enabled graceful termination of +// http.Server. +package httpdown + +import ( + "crypto/tls" + "fmt" + "net" + "net/http" + "os" + "os/signal" + "sync" + "syscall" + "time" + + "github.com/facebookgo/clock" + "github.com/facebookgo/stats" +) + +const ( + defaultStopTimeout = time.Minute + defaultKillTimeout = time.Minute +) + +// A Server allows encapsulates the process of accepting new connections and +// serving them, and gracefully shutting down the listener without dropping +// active connections. +type Server interface { + // Wait waits for the serving loop to finish. This will happen when Stop is + // called, at which point it returns no error, or if there is an error in the + // serving loop. You must call Wait after calling Serve or ListenAndServe. + Wait() error + + // Stop stops the listener. It will block until all connections have been + // closed. + Stop() error +} + +// HTTP defines the configuration for serving a http.Server. Multiple calls to +// Serve or ListenAndServe can be made on the same HTTP instance. The default +// timeouts of 1 minute each result in a maximum of 2 minutes before a Stop() +// returns. +type HTTP struct { + // StopTimeout is the duration before we begin force closing connections. + // Defaults to 1 minute. + StopTimeout time.Duration + + // KillTimeout is the duration before which we completely give up and abort + // even though we still have connected clients. This is useful when a large + // number of client connections exist and closing them can take a long time. + // Note, this is in addition to the StopTimeout. Defaults to 1 minute. + KillTimeout time.Duration + + // Stats is optional. If provided, it will be used to record various metrics. + Stats stats.Client + + // Clock allows for testing timing related functionality. Do not specify this + // in production code. + Clock clock.Clock +} + +// Serve provides the low-level API which is useful if you're creating your own +// net.Listener. +func (h HTTP) Serve(s *http.Server, l net.Listener) Server { + stopTimeout := h.StopTimeout + if stopTimeout == 0 { + stopTimeout = defaultStopTimeout + } + killTimeout := h.KillTimeout + if killTimeout == 0 { + killTimeout = defaultKillTimeout + } + klock := h.Clock + if klock == nil { + klock = clock.New() + } + + ss := &server{ + stopTimeout: stopTimeout, + killTimeout: killTimeout, + stats: h.Stats, + clock: klock, + oldConnState: s.ConnState, + listener: l, + server: s, + serveDone: make(chan struct{}), + serveErr: make(chan error, 1), + new: make(chan net.Conn), + active: make(chan net.Conn), + idle: make(chan net.Conn), + closed: make(chan net.Conn), + stop: make(chan chan struct{}), + kill: make(chan chan struct{}), + } + s.ConnState = ss.connState + go ss.manage() + go ss.serve() + return ss +} + +// ListenAndServe returns a Server for the given http.Server. It is equivalent +// to ListenAndServe from the standard library, but returns immediately. +// Requests will be accepted in a background goroutine. If the http.Server has +// a non-nil TLSConfig, a TLS enabled listener will be setup. +func (h HTTP) ListenAndServe(s *http.Server) (Server, error) { + addr := s.Addr + if addr == "" { + if s.TLSConfig == nil { + addr = ":http" + } else { + addr = ":https" + } + } + l, err := net.Listen("tcp", addr) + if err != nil { + stats.BumpSum(h.Stats, "listen.error", 1) + return nil, err + } + if s.TLSConfig != nil { + l = tls.NewListener(l, s.TLSConfig) + } + return h.Serve(s, l), nil +} + +// server manages the serving process and allows for gracefully stopping it. +type server struct { + stopTimeout time.Duration + killTimeout time.Duration + stats stats.Client + clock clock.Clock + + oldConnState func(net.Conn, http.ConnState) + server *http.Server + serveDone chan struct{} + serveErr chan error + listener net.Listener + + new chan net.Conn + active chan net.Conn + idle chan net.Conn + closed chan net.Conn + stop chan chan struct{} + kill chan chan struct{} + + stopOnce sync.Once + stopErr error +} + +func (s *server) connState(c net.Conn, cs http.ConnState) { + if s.oldConnState != nil { + s.oldConnState(c, cs) + } + + switch cs { + case http.StateNew: + s.new <- c + case http.StateActive: + s.active <- c + case http.StateIdle: + s.idle <- c + case http.StateHijacked, http.StateClosed: + s.closed <- c + } +} + +func (s *server) manage() { + defer func() { + close(s.new) + close(s.active) + close(s.idle) + close(s.closed) + close(s.stop) + close(s.kill) + }() + + var stopDone chan struct{} + + conns := map[net.Conn]http.ConnState{} + var countNew, countActive, countIdle float64 + + // decConn decrements the count associated with the current state of the + // given connection. + decConn := func(c net.Conn) { + switch conns[c] { + default: + panic(fmt.Errorf("unknown existing connection: %s", c)) + case http.StateNew: + countNew-- + case http.StateActive: + countActive-- + case http.StateIdle: + countIdle-- + } + } + + // setup a ticker to report various values every minute. if we don't have a + // Stats implementation provided, we Stop it so it never ticks. + statsTicker := s.clock.Ticker(time.Minute) + if s.stats == nil { + statsTicker.Stop() + } + + for { + select { + case <-statsTicker.C: + // we'll only get here when s.stats is not nil + s.stats.BumpAvg("http-state.new", countNew) + s.stats.BumpAvg("http-state.active", countActive) + s.stats.BumpAvg("http-state.idle", countIdle) + s.stats.BumpAvg("http-state.total", countNew+countActive+countIdle) + case c := <-s.new: + conns[c] = http.StateNew + countNew++ + case c := <-s.active: + decConn(c) + countActive++ + + conns[c] = http.StateActive + case c := <-s.idle: + decConn(c) + countIdle++ + + conns[c] = http.StateIdle + + // if we're already stopping, close it + if stopDone != nil { + c.Close() + } + case c := <-s.closed: + stats.BumpSum(s.stats, "conn.closed", 1) + decConn(c) + delete(conns, c) + + // if we're waiting to stop and are all empty, we just closed the last + // connection and we're done. + if stopDone != nil && len(conns) == 0 { + close(stopDone) + return + } + case stopDone = <-s.stop: + // if we're already all empty, we're already done + if len(conns) == 0 { + close(stopDone) + return + } + + // close current idle connections right away + for c, cs := range conns { + if cs == http.StateIdle { + c.Close() + } + } + + // continue the loop and wait for all the ConnState updates which will + // eventually close(stopDone) and return from this goroutine. + + case killDone := <-s.kill: + // force close all connections + stats.BumpSum(s.stats, "kill.conn.count", float64(len(conns))) + for c := range conns { + c.Close() + } + + // don't block the kill. + close(killDone) + + // continue the loop and we wait for all the ConnState updates and will + // return from this goroutine when we're all done. otherwise we'll try to + // send those ConnState updates on closed channels. + + } + } +} + +func (s *server) serve() { + stats.BumpSum(s.stats, "serve", 1) + s.serveErr <- s.server.Serve(s.listener) + close(s.serveDone) + close(s.serveErr) +} + +func (s *server) Wait() error { + if err := <-s.serveErr; !isUseOfClosedError(err) { + return err + } + return nil +} + +func (s *server) Stop() error { + s.stopOnce.Do(func() { + defer stats.BumpTime(s.stats, "stop.time").End() + stats.BumpSum(s.stats, "stop", 1) + + // first disable keep-alive for new connections + s.server.SetKeepAlivesEnabled(false) + + // then close the listener so new connections can't connect come thru + closeErr := s.listener.Close() + <-s.serveDone + + // then trigger the background goroutine to stop and wait for it + stopDone := make(chan struct{}) + s.stop <- stopDone + + // wait for stop + select { + case <-stopDone: + case <-s.clock.After(s.stopTimeout): + defer stats.BumpTime(s.stats, "kill.time").End() + stats.BumpSum(s.stats, "kill", 1) + + // stop timed out, wait for kill + killDone := make(chan struct{}) + s.kill <- killDone + select { + case <-killDone: + case <-s.clock.After(s.killTimeout): + // kill timed out, give up + stats.BumpSum(s.stats, "kill.timeout", 1) + } + } + + if closeErr != nil && !isUseOfClosedError(closeErr) { + stats.BumpSum(s.stats, "listener.close.error", 1) + s.stopErr = closeErr + } + }) + return s.stopErr +} + +func isUseOfClosedError(err error) bool { + if err == nil { + return false + } + if opErr, ok := err.(*net.OpError); ok { + err = opErr.Err + } + return err.Error() == "use of closed network connection" +} + +// ListenAndServe is a convenience function to serve and wait for a SIGTERM +// or SIGINT before shutting down. +func ListenAndServe(s *http.Server, hd *HTTP) error { + if hd == nil { + hd = &HTTP{} + } + hs, err := hd.ListenAndServe(s) + if err != nil { + return err + } + + waiterr := make(chan error, 1) + go func() { + defer close(waiterr) + waiterr <- hs.Wait() + }() + + signals := make(chan os.Signal, 10) + signal.Notify(signals, syscall.SIGTERM, syscall.SIGINT) + + select { + case err := <-waiterr: + if err != nil { + return err + } + case <-signals: + signal.Stop(signals) + if err := hs.Stop(); err != nil { + return err + } + if err := <-waiterr; err != nil { + return err + } + } + return nil +} diff --git a/vendor/github.com/facebookgo/httpdown/license b/vendor/github.com/facebookgo/httpdown/license new file mode 100644 index 0000000000..d849082ffb --- /dev/null +++ b/vendor/github.com/facebookgo/httpdown/license @@ -0,0 +1,30 @@ +BSD License + +For httpdown 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. diff --git a/vendor/github.com/facebookgo/httpdown/patents b/vendor/github.com/facebookgo/httpdown/patents new file mode 100644 index 0000000000..f7133456a2 --- /dev/null +++ b/vendor/github.com/facebookgo/httpdown/patents @@ -0,0 +1,33 @@ +Additional Grant of Patent Rights Version 2 + +"Software" means the httpdown software distributed by Facebook, Inc. + +Facebook, Inc. ("Facebook") hereby grants to each recipient of the Software +("you") a perpetual, worldwide, royalty-free, non-exclusive, irrevocable +(subject to the termination provision below) license under any Necessary +Claims, to make, have made, use, sell, offer to sell, import, and otherwise +transfer the Software. For avoidance of doubt, no license is granted under +Facebookâs rights in any patent claims that are infringed by (i) modifications +to the Software made by you or any third party or (ii) the Software in +combination with any software or other technology. + +The license granted hereunder will terminate, automatically and without notice, +if you (or any of your subsidiaries, corporate affiliates or agents) initiate +directly or indirectly, or take a direct financial interest in, any Patent +Assertion: (i) against Facebook or any of its subsidiaries or corporate +affiliates, (ii) against any party if such Patent Assertion arises in whole or +in part from any software, technology, product or service of Facebook or any of +its subsidiaries or corporate affiliates, or (iii) against any party relating +to the Software. Notwithstanding the foregoing, if Facebook or any of its +subsidiaries or corporate affiliates files a lawsuit alleging patent +infringement against you in the first instance, and you respond by filing a +patent infringement counterclaim in that lawsuit against that party that is +unrelated to the Software, the license granted hereunder will not terminate +under section (i) of this paragraph due to such counterclaim. + +A "Necessary Claim" is a claim of a patent owned by Facebook that is +necessarily infringed by the Software standing alone. + +A "Patent Assertion" is any lawsuit or other action alleging direct, indirect, +or contributory infringement or inducement to infringe any patent, including a +cross-claim or counterclaim. diff --git a/vendor/github.com/facebookgo/httpdown/readme.md b/vendor/github.com/facebookgo/httpdown/readme.md new file mode 100644 index 0000000000..d5fa245dbc --- /dev/null +++ b/vendor/github.com/facebookgo/httpdown/readme.md @@ -0,0 +1,41 @@ +httpdown [](https://travis-ci.org/facebookgo/httpdown) +======== + +Documentation: https://godoc.org/github.com/facebookgo/httpdown + +Package httpdown provides a library that makes it easy to build a HTTP server +that can be shutdown gracefully (that is, without dropping any connections). + +If you want graceful restart and not just graceful shutdown, look at the +[grace](https://github.com/facebookgo/grace) package which uses this package +underneath but also provides graceful restart. + +Usage +----- + +Demo HTTP Server with graceful termination: +https://github.com/facebookgo/httpdown/blob/master/httpdown_example/main.go + +1. Install the demo application + + go get github.com/facebookgo/httpdown/httpdown_example + +1. Start it in the first terminal + + httpdown_example + + This will output something like: + + 2014/11/18 21:57:50 serving on http://127.0.0.1:8080/ with pid 17 + +1. In a second terminal start a slow HTTP request + + curl 'http://localhost:8080/?duration=20s' + +1. In a third terminal trigger a graceful shutdown (using the pid from your output): + + kill -TERM 17 + +This will demonstrate that the slow request was served before the server was +shutdown. You could also have used `Ctrl-C` instead of `kill` as the example +application triggers graceful shutdown on TERM or INT signals. |