Files
nats-server/server/service_windows.go
Ivan Kozlovic 9cddf0fcdf [FIXED] Windows Docker Image
The use of the `svc` API prevented the NATS Server to run as
a container on both nanoserver and windowsservercore Docker images.
An attempt was made to replace svc.Debug with normal server.Start()
if detected to be interactive, however, that did not work. The
fact of detecting if interactive or not already requires connecting
to the service controller apparently.
This change looks up for an environment variable (NATS_DOCKERIZED)
and if set to "1", will not make use of the `svc` package.
This environment variable will be set in the Docker image (in
nats-docker/windows/nanoserver/Dockerfile and windowsservercore/Dockerfile).

Resolves #543
2017-07-18 19:00:17 -06:00

111 lines
2.8 KiB
Go

// Copyright 2012-2017 Apcera Inc. All rights reserved.
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
}