// ServeHandler serves the handler on the listener and returns a function that
// serves an additional listener using a function that takes a connection. The
// returned function can be called multiple times.
func ServeHandler(
stopper *stop.Stopper, handler http.Handler, ln net.Listener, tlsConfig *tls.Config,
) func(net.Listener, func(net.Conn)) error {
var mu sync.Mutex
activeConns := make(map[net.Conn]struct{})
logger := log.NewStdLogger(log.ErrorLog)
httpServer := http.Server{
Handler: handler,
TLSConfig: tlsConfig,
ConnState: func(conn net.Conn, state http.ConnState) {
mu.Lock()
switch state {
case http.StateNew:
activeConns[conn] = struct{}{}
case http.StateClosed:
delete(activeConns, conn)
}
mu.Unlock()
},
ErrorLog: logger,
}
// net/http.(*Server).Serve/http2.ConfigureServer are not thread safe with
// respect to net/http.(*Server).TLSConfig, so we call it synchronously here.
if err := http2.ConfigureServer(&httpServer, nil); err != nil {
log.Fatal(err)
}
stopper.RunWorker(func() {
FatalIfUnexpected(httpServer.Serve(ln))
<-stopper.ShouldStop()
mu.Lock()
for conn := range activeConns {
conn.Close()
}
mu.Unlock()
})
logFn := logger.Printf
return func(l net.Listener, serveConn func(net.Conn)) error {
// Inspired by net/http.(*Server).Serve
var tempDelay time.Duration // how long to sleep on accept failure
for {
rw, e := l.Accept()
if e != nil {
if ne, ok := e.(net.Error); ok && ne.Temporary() {
if tempDelay == 0 {
tempDelay = 5 * time.Millisecond
} else {
tempDelay *= 2
}
if max := 1 * time.Second; tempDelay > max {
tempDelay = max
}
logFn("http: Accept error: %v; retrying in %v", e, tempDelay)
time.Sleep(tempDelay)
continue
}
return e
}
tempDelay = 0
go func() {
httpServer.ConnState(rw, http.StateNew) // before Serve can return
serveConn(rw)
httpServer.ConnState(rw, http.StateClosed)
}()
}
}
}
if err != nil {
return ln, err
}
stopper.RunWorker(func() {
<-stopper.ShouldDrain()
server.Stop()
})
stopper.RunWorker(func() {
FatalIfUnexpected(server.Serve(ln))
})
return ln, nil
}
var httpLogger = log.NewStdLogger(log.ErrorLog)
// Server is a thin wrapper around http.Server. See MakeServer for more detail.
type Server struct {
*http.Server
}
// MakeServer constructs a Server that tracks active connections, closing them
// when signalled by stopper.
func MakeServer(stopper *stop.Stopper, tlsConfig *tls.Config, handler http.Handler) Server {
var mu sync.Mutex
activeConns := make(map[net.Conn]struct{})
server := Server{
Server: &http.Server{
Handler: handler,
TLSConfig: tlsConfig,