facebookarchive / httpdown

Package httpdown provides http.ConnState enabled graceful termination of http.Server.

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 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
   

2. 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
   

3. In a second terminal start a slow HTTP request

    curl 'http://localhost:8080/?duration=20s'
   

4. 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.

httpdown's Issues

test result in i386 always fail

after compiled with golang 1.8 in i386 setup i got this error:

--- FAIL: TestNewRequestAfterStop (0.01s)
	ensure.go:65: ���������������httpdown_test.go:236: expected error: "(connection refused|connection reset by peer)$" but got a nil error

Access to internal listener variable

When passing a listening address with port 0, a suiting port number is chosen. However, finding out which port was chosen requires access to the listener variable of type net.Listener (?). Private variables makes this to difficult to solve without hacking the library directly.

panic: sync: negative WaitGroup counter

When calling Stop on the httpdown server, i get an panic: sync: negative WaitGroup counter error.

    server := &http.Server{
        Addr:    addr,
        Handler: handlers.CORS()(k.router),
    }

    hd := &httpdown.HTTP{
        StopTimeout: 10 * time.Second,
        KillTimeout: 1 * time.Second,
    }

    if listener, err := net.Listen("tcp", addr); err == nil {
        s := hd.Serve(server, listener)

        // Receive on the shutdown channel will block as
        // nothing is ever sent down it, however once it closes
        // the lock is released and we can tell the server to stop,
        // once stop finishes we can then tell the shutdowner we
        // are done.
        <-k.ShutdownChan()
        s.Stop()
        k.ShutdownComplete()
    }

bug: test TLS always fail in i386 env

test TLS always fail in i386 env using golang 1.8:

seems the httpdown facebook need network connection to work that test?

--- PASS: TestTLS (0.10s)
FAIL
FAIL	github.com/facebookgo/httpdown	0.118s
?   	github.com/facebookgo/httpdown/httpdown_example	[no test files]
dh_auto_test: go test -v -p 10 github.com/facebookgo/httpdown github.com/facebookgo/httpdown/httpdown_example returned exit code 1

Use vendoring for your dependencies

Hi

Since Go 1.6, it is recommended to vendor the dependencies:

https://golang.org/doc/go1.6#go_command

Could you do this in this project? I.e. vendor facebookgo/clock and facebookgo/stats (I recommend git submodules, it works great in my projects).

This way, the exact version of the dependencies is fixed, and in my project, I only have to directly depend on httpdown, and not manually transitively vendor all its dependencies.

Thank you.

add tcpKeepAliveListener

The net/http code uses its own tcpKeepAliveListener in its Listen helpers to prevent expired TCP connections from remaining open too long (e.g. laptops being closed mid-download).

I think it makes sense for httpdown to do the same. I don't see equivalent code to it.

Does this make sense to y'all?

Example usage here: https://github.com/golang/go/blob/c80e0d374ba3caf8ee32c6fe4a5474fa33928086/src/net/http/server.go#L2219

Create annotated tags for releases

Hi

It would be great if you tagged the current HEAD with v1.0.0, and in the future, occasionally bump the version and make new tags with new releases. I suggest using the semver.org versioning scheme, where you have major.minor.patch, and you bump the major for incompatible changes and the minor for compatible changes to the API.