tile38/vendor/github.com/nats-io/gnatsd/server/service_windows.go

122 lines
3.3 KiB
Go

// Copyright 2012-2018 The NATS Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package server
import (
"os"
"time"
"golang.org/x/sys/windows/svc"
"golang.org/x/sys/windows/svc/debug"
)
const (
serviceName = "gnatsd"
reopenLogCode = 128
reopenLogCmd = svc.Cmd(reopenLogCode)
acceptReopenLog = svc.Accepted(reopenLogCode)
)
// winServiceWrapper implements the svc.Handler interface for implementing
// gnatsd as a Windows service.
type winServiceWrapper struct {
server *Server
}
var dockerized = false
func init() {
if v, exists := os.LookupEnv("NATS_DOCKERIZED"); exists && v == "1" {
dockerized = true
}
}
// Execute will be called by the package code at the start of
// the service, and the service will exit once Execute completes.
// Inside Execute you must read service change requests from r and
// act accordingly. You must keep service control manager up to date
// about state of your service by writing into s as required.
// args contains service name followed by argument strings passed
// to the service.
// You can provide service exit code in exitCode return parameter,
// with 0 being "no error". You can also indicate if exit code,
// if any, is service specific or not by using svcSpecificEC
// parameter.
func (w *winServiceWrapper) Execute(args []string, changes <-chan svc.ChangeRequest,
status chan<- svc.Status) (bool, uint32) {
status <- svc.Status{State: svc.StartPending}
go w.server.Start()
// Wait for accept loop(s) to be started
if !w.server.ReadyForConnections(10 * time.Second) {
// Failed to start.
return false, 1
}
status <- svc.Status{
State: svc.Running,
Accepts: svc.AcceptStop | svc.AcceptShutdown | svc.AcceptParamChange | acceptReopenLog,
}
loop:
for change := range changes {
switch change.Cmd {
case svc.Interrogate:
status <- change.CurrentStatus
case svc.Stop, svc.Shutdown:
w.server.Shutdown()
break loop
case reopenLogCmd:
// File log re-open for rotating file logs.
w.server.ReOpenLogFile()
case svc.ParamChange:
if err := w.server.Reload(); err != nil {
w.server.Errorf("Failed to reload server configuration: %s", err)
}
default:
w.server.Debugf("Unexpected control request: %v", change.Cmd)
}
}
status <- svc.Status{State: svc.StopPending}
return false, 0
}
// Run starts the NATS server as a Windows service.
func Run(server *Server) error {
if dockerized {
server.Start()
return nil
}
run := svc.Run
isInteractive, err := svc.IsAnInteractiveSession()
if err != nil {
return err
}
if isInteractive {
run = debug.Run
}
return run(serviceName, &winServiceWrapper{server})
}
// isWindowsService indicates if NATS is running as a Windows service.
func isWindowsService() bool {
if dockerized {
return false
}
isInteractive, _ := svc.IsAnInteractiveSession()
return !isInteractive
}