OP#792 initial commit after fork

internal/http/server.go

@@ -0,0 +1,238 @@
+// Copyright (c) 2015-2023 MinIO, Inc.
+//
+// This file is part of MinIO Object Storage stack
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package http
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"log"
+	"net"
+	"net/http"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/dustin/go-humanize"
+)
+
+var (
+	// GlobalMinIOVersion - is sent in the header to all http targets
+	GlobalMinIOVersion string
+
+	// GlobalDeploymentID - is sent in the header to all http targets
+	GlobalDeploymentID string
+)
+
+const (
+	// DefaultIdleTimeout for idle inactive connections
+	DefaultIdleTimeout = 30 * time.Second
+
+	// DefaultReadHeaderTimeout for very slow inactive connections
+	DefaultReadHeaderTimeout = 30 * time.Second
+
+	// DefaultMaxHeaderBytes - default maximum HTTP header size in bytes.
+	DefaultMaxHeaderBytes = 1 * humanize.MiByte
+)
+
+// Server - extended http.Server supports multiple addresses to serve and enhanced connection handling.
+type Server struct {
+	http.Server
+	Addrs         []string      // addresses on which the server listens for new connection.
+	TCPOptions    TCPOptions    // all the configurable TCP conn specific configurable options.
+	listenerMutex sync.Mutex    // to guard 'listener' field.
+	listener      *httpListener // HTTP listener for all 'Addrs' field.
+	inShutdown    uint32        // indicates whether the server is in shutdown or not
+	requestCount  int32         // counter holds no. of request in progress.
+}
+
+// GetRequestCount - returns number of request in progress.
+func (srv *Server) GetRequestCount() int {
+	return int(atomic.LoadInt32(&srv.requestCount))
+}
+
+// Init - init HTTP server
+func (srv *Server) Init(listenCtx context.Context, listenErrCallback func(listenAddr string, err error)) (serve func() error, err error) {
+	// Take a copy of server fields.
+	var tlsConfig *tls.Config
+	if srv.TLSConfig != nil {
+		tlsConfig = srv.TLSConfig.Clone()
+	}
+	handler := srv.Handler // if srv.Handler holds non-synced state -> possible data race
+
+	// Create new HTTP listener.
+	var listener *httpListener
+	listener, listenErrs := newHTTPListener(
+		listenCtx,
+		srv.Addrs,
+		srv.TCPOptions,
+	)
+
+	var interfaceFound bool
+	for i := range listenErrs {
+		if listenErrs[i] != nil {
+			listenErrCallback(srv.Addrs[i], listenErrs[i])
+		} else {
+			interfaceFound = true
+		}
+	}
+	if !interfaceFound {
+		return nil, errors.New("no available interface found")
+	}
+
+	// Wrap given handler to do additional
+	// * return 503 (service unavailable) if the server in shutdown.
+	wrappedHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// If server is in shutdown.
+		if atomic.LoadUint32(&srv.inShutdown) != 0 {
+			// To indicate disable keep-alive, server is shutting down.
+			w.Header().Set("Connection", "close")
+
+			// Add 1 minute retry header, incase-client wants to honor it
+			w.Header().Set(RetryAfter, "60")
+
+			w.WriteHeader(http.StatusServiceUnavailable)
+			w.Write([]byte(http.ErrServerClosed.Error()))
+			return
+		}
+
+		atomic.AddInt32(&srv.requestCount, 1)
+		defer atomic.AddInt32(&srv.requestCount, -1)
+
+		// Handle request using passed handler.
+		handler.ServeHTTP(w, r)
+	})
+
+	srv.listenerMutex.Lock()
+	srv.Handler = wrappedHandler
+	srv.listener = listener
+	srv.listenerMutex.Unlock()
+
+	var l net.Listener = listener
+	if tlsConfig != nil {
+		l = tls.NewListener(listener, tlsConfig)
+	}
+
+	serve = func() error {
+		return srv.Serve(l)
+	}
+
+	return serve, err
+}
+
+// Shutdown - shuts down HTTP server.
+func (srv *Server) Shutdown() error {
+	srv.listenerMutex.Lock()
+	if srv.listener == nil {
+		srv.listenerMutex.Unlock()
+		return http.ErrServerClosed
+	}
+	srv.listenerMutex.Unlock()
+
+	if atomic.AddUint32(&srv.inShutdown, 1) > 1 {
+		// shutdown in progress
+		return http.ErrServerClosed
+	}
+
+	// Close underneath HTTP listener.
+	srv.listenerMutex.Lock()
+	err := srv.listener.Close()
+	srv.listenerMutex.Unlock()
+	if err != nil {
+		return err
+	}
+
+	// Wait for opened connection to be closed up to Shutdown timeout.
+	return nil
+}
+
+// UseIdleTimeout configure idle connection timeout
+func (srv *Server) UseIdleTimeout(d time.Duration) *Server {
+	srv.IdleTimeout = d
+	return srv
+}
+
+// UseReadTimeout configure connection request read timeout.
+func (srv *Server) UseReadTimeout(d time.Duration) *Server {
+	srv.ReadTimeout = d
+	return srv
+}
+
+// UseReadHeaderTimeout configure read header timeout
+func (srv *Server) UseReadHeaderTimeout(d time.Duration) *Server {
+	srv.ReadHeaderTimeout = d
+	return srv
+}
+
+// UseWriteTimeout configure connection response write timeout.
+func (srv *Server) UseWriteTimeout(d time.Duration) *Server {
+	srv.WriteTimeout = d
+	return srv
+}
+
+// UseHandler configure final handler for this HTTP *Server
+func (srv *Server) UseHandler(h http.Handler) *Server {
+	srv.Handler = h
+	return srv
+}
+
+// UseTLSConfig pass configured TLSConfig for this HTTP *Server
+func (srv *Server) UseTLSConfig(cfg *tls.Config) *Server {
+	srv.TLSConfig = cfg
+	return srv
+}
+
+// UseBaseContext use custom base context for this HTTP *Server
+func (srv *Server) UseBaseContext(ctx context.Context) *Server {
+	srv.BaseContext = func(listener net.Listener) context.Context {
+		return ctx
+	}
+	return srv
+}
+
+// UseCustomLogger use customized logger for this HTTP *Server
+func (srv *Server) UseCustomLogger(l *log.Logger) *Server {
+	srv.ErrorLog = l
+	return srv
+}
+
+// UseTCPOptions use custom TCP options on raw socket
+func (srv *Server) UseTCPOptions(opts TCPOptions) *Server {
+	srv.TCPOptions = opts
+	return srv
+}
+
+// NewServer - creates new HTTP server using given arguments.
+func NewServer(addrs []string) *Server {
+	httpServer := &Server{
+		Addrs: addrs,
+	}
+	// This is not configurable for now.
+	httpServer.MaxHeaderBytes = DefaultMaxHeaderBytes
+	return httpServer
+}
+
+// SetMinIOVersion -- MinIO version from the main package is set here
+func SetMinIOVersion(version string) {
+	GlobalMinIOVersion = version
+}
+
+// SetDeploymentID -- Deployment Id from the main package is set here
+func SetDeploymentID(deploymentID string) {
+	GlobalDeploymentID = deploymentID
+}