func main() {
if *debugMode {
log.SetLevel(log.DebugLevel)
} else if *noWarn {
log.SetLevel(log.ErrorLevel)
}
// Create channel for ProcessStats to trigger a sample
psChan := make(chan agents.ProcessStatCommand)
// Incoming remote command channel (new with each reconnect)
rcChan := make(chan chan agents.RemoteControlCommand)
args := flag.Args()
var cmdArgs []string
var cmd string
if len(args) > 0 {
cmd = args[0]
} else {
log.Fatal("Did you forget a command to run?")
return
}
log.Debugf("cmd: %s cmdArgs: %q\n", cmd, cmdArgs)
done := make(chan error)
// Initialize job
job, err := agents.NewControlledProcess(cmd, args, done, *stdoutByteLimit)
if err != nil {
log.Fatalf("Failed to create a NewControlledProcess: %s\n", err)
return
}
log.Debugf("%#v\n", job)
signals := make(chan os.Signal, 1)
signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP, syscall.SIGQUIT)
timer, err := agents.NewTimer(*wallclockTimeout)
if err != nil {
log.Warnln("Error returned creating timeout agent", err)
}
log.Debugf("Starting timer with timeout of: %v\n", *wallclockTimeout)
timer.Start()
sess := session{
job: job,
exchange: *exchange,
rcRoutingKey: *rmtKey,
psChan: psChan,
rcChan: rcChan,
amqpConfig: amqp.Config{
Properties: amqp.Table{
"product": "proc_box",
"version": "master",
},
},
multiRmtKey: *multiRmtKey,
}
go redial(sess)
go monitor(signals, rcChan, job, psChan, timer, done)
err = <-done
elapsedTime, _ := timer.ElapsedTime()
// Print to standard out
fmt.Printf("Task elapsed time: %.2f seconds.\n", elapsedTime.Seconds())
if err != nil {
if exiterr, ok := err.(*exec.ExitError); ok {
// Non-zero exit code
if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
exitStatus := status.ExitStatus()
log.Debugf("Exit Status: %d\n", exitStatus)
os.Exit(exitStatus)
}
} else {
log.Debugf("cmd.Wait: %v\n", err)
}
} else {
os.Exit(0)
}
}
func monitor(
signals chan os.Signal,
rcChanChan chan chan agents.RemoteControlCommand,
job agents.JobControl,
psChan chan agents.ProcessStatCommand,
timer agents.Timer,
done chan error,
) {
// Catch any panics here to ensure we kill the child process before going
// to our own doom.
defer func() {
if e := recover(); e != nil {
job.Kill(-9)
panic(e)
}
}()
var logSampling <-chan time.Time
var err error
if *stdoutByteLimit > 0 {
ticker := time.NewTicker(100 * time.Millisecond)
// Replace the time channel with an actual ticker if this is in use
logSampling = ticker.C
}
var rcChan chan agents.RemoteControlCommand
for {
select {
case rcChan = <-rcChanChan:
// Catch incoming signals and operate on them as if they were remote commands
case sig := <-signals:
switch sig {
case syscall.SIGINT:
log.Debugln("Caught SIGINT, graceful shutdown")
// Initiate non-blocking send
select {
case psChan <- agents.ProcessStatCommand{}:
log.Debugln("Sending psChan a msg to sample")
default:
log.Debugln("SIGINT failed to send a sample msg on the psChan")
}
err = job.Stop()
case syscall.SIGTERM:
log.Debugln("Caught SIGTERM, end abruptly")
job.Kill(-9)
case syscall.SIGHUP:
log.Debugln("Caught SIGHUP, emit stats")
// Initiate non-blocking send
select {
case psChan <- agents.ProcessStatCommand{}:
log.Debugln("Sending psChan a msg to sample")
default:
log.Debugln("SIGHUP failed to send a sample msg on the psChan")
}
case syscall.SIGQUIT:
log.Debugln("Caught SIGQUIT, graceful shutdown")
select {
case psChan <- agents.ProcessStatCommand{}:
log.Debugln("Sending psChan a msg to sample")
default:
log.Debugln("SIGQUIT failed to send a sample msg on the psChan")
}
err = job.Stop()
}
// Process incoming remote commands, toss unknown requests
case cmd := <-rcChan:
log.Debugf("Got a command %#v\n", cmd)
switch cmd.Command {
case "suspend":
log.Debugln("RemoteCommand: Suspend")
job.Suspend()
case "resume":
log.Debugln("RemoteCommand: Resume")
job.Resume()
case "kill":
log.Debugln("RemoteCommand: Kill")
var args int64
if len(cmd.Arguments) == 0 {
args = -9
} else {
args, err = strconv.ParseInt(cmd.Arguments[0], 10, 32)
if err != nil {
log.Warnf("Unable to parse kill command argument[0] into int: %s\n", err)
args = -9
}
}
job.Kill(args)
case "stop":
log.Debugln("RemoteCommand: Stop")
select {
case psChan <- agents.ProcessStatCommand{}:
log.Debugln("Sending psChan a msg to sample")
default:
log.Debugln("RC Stop failed to send a sample msg on the psChan")
}
if err = job.Stop(); err != nil {
log.Fatalf("Error received while stopping sub-process: %s\n", err)
}
case "sample":
log.Debugln("RemoteCommand: Sample")
select {
case psChan <- agents.ProcessStatCommand{}:
log.Debugln("Sending psChan a msg to sample")
default:
log.Debugln("RC Sample failed to send a sample msg on the psChan")
}
case "change_sample_rate":
log.Debugln("RemoteCommand: Change Stats Sample Rate")
if len(cmd.Arguments) > 0 {
log.Debugf("change_sample_rate arg[0]: %s\n", cmd.Arguments[0])
d, err := time.ParseDuration(cmd.Arguments[0])
if err == nil {
select {
case psChan <- agents.ProcessStatCommand{
TimeUpdate: true,
NewTime: d}:
log.Debugln("Sending psChan a msg to update the ticker")
default:
log.Debugln("RC change_sample_rate failed to send a msg")
}
} else {
log.Warnf("Unparseable duration argument to command change_sample_rate")
}
} else {
log.Warnf("Missing argument to command change_sample_rate")
}
case "timer_reset":
log.Debugln("RemoteCommand: Timer Reset")
if err = timer.Reset(); err != nil {
log.Fatalf("Error received from timer calling Reset: %s\n", err)
}
case "timer_start":
log.Debugln("RemoteCommand: Timer Start")
if err = timer.Start(); err != nil {
log.Fatalf("Error received from timer calling Start: %s\n", err)
}
case "timer_stop":
log.Debugln("RemoteCommand: Timer Stop")
if err = timer.Stop(); err != nil {
log.Fatalf("Error received from timer calling Stop: %s\n", err)
}
case "timer_resume":
log.Debugln("RemoteCommand: Timer Resume")
if err = timer.Resume(); err != nil {
log.Fatalf("Error received from timer calling Resume: %s\n", err)
}
default:
log.Debugf("Unknown command: %s\n", cmd)
}
case timeoutMsg := <-timer.Done():
log.Debugf("Timer timeout message: %s\n", timeoutMsg)
if err = job.Stop(); err != nil {
log.Fatalf("Error received while stopping sub-process: %v\n", err)
// If there was an error stopping the process, kill the porcess.
job.Kill(-9)
}
case jobDone := <-job.Done():
log.Debugln("Command exited gracefully; shutting down.")
done <- jobDone
case _ = <-logSampling:
if job.StdoutByteCount() > 2*(*stdoutByteLimit) {
err = job.Kill(-9)
} else if job.StdoutByteCount() > *stdoutByteLimit {
err = job.Stop()
}
}
}
}