open-nomad/client/allocrunner/taskrunner/lifecycle.go
Michael Schurter f7d4428855 client: simplify kill logic
Remove runLaunched tracking as Run is *always* called for killable
TaskRunners. TaskRunners which fail before Run can be called (during
NewTaskRunner or Restore) are not killable as they're never added to the
client's alloc map.
2019-04-04 15:18:33 -07:00

88 lines
2 KiB
Go

package taskrunner
import (
"context"
"github.com/hashicorp/nomad/nomad/structs"
)
// Restart a task. Returns immediately if no task is running. Blocks until
// existing task exits or passed-in context is canceled.
func (tr *TaskRunner) Restart(ctx context.Context, event *structs.TaskEvent, failure bool) error {
tr.logger.Trace("Restart requested", "failure", failure)
// Grab the handle
handle := tr.getDriverHandle()
// Check it is running
if handle == nil {
return ErrTaskNotRunning
}
// Emit the event since it may take a long time to kill
tr.EmitEvent(event)
// Run the pre-kill hooks prior to restarting the task
tr.preKill()
// Tell the restart tracker that a restart triggered the exit
tr.restartTracker.SetRestartTriggered(failure)
// Kill the task using an exponential backoff in-case of failures.
if err := tr.killTask(handle); err != nil {
// We couldn't successfully destroy the resource created.
tr.logger.Error("failed to kill task. Resources may have been leaked", "error", err)
}
// Drain the wait channel or wait for the request context to be canceled
waitCh, err := handle.WaitCh(ctx)
if err != nil {
return err
}
select {
case <-waitCh:
case <-ctx.Done():
}
return nil
}
func (tr *TaskRunner) Signal(event *structs.TaskEvent, s string) error {
tr.logger.Trace("Signal requested", "signal", s)
// Grab the handle
handle := tr.getDriverHandle()
// Check it is running
if handle == nil {
return ErrTaskNotRunning
}
// Emit the event
tr.EmitEvent(event)
// Send the signal
return handle.Signal(s)
}
// Kill a task. Blocks until task exits or context is canceled. State is set to
// dead.
func (tr *TaskRunner) Kill(ctx context.Context, event *structs.TaskEvent) error {
tr.logger.Trace("Kill requested", "event_type", event.Type, "event_reason", event.KillReason)
// Cancel the task runner to break out of restart delay or the main run
// loop.
tr.killCtxCancel()
// Emit kill event
tr.EmitEvent(event)
select {
case <-tr.WaitCh():
case <-ctx.Done():
return ctx.Err()
}
return tr.getKillErr()
}