When a task is restored after a client restart, the template runner will
create a new lease for any dynamic secret (ex. Consul or PKI secrets
engines). But because this lease is being created in the prestart hook, we
don't trigger the `change_mode`.
This changeset uses the the existence of the task handle to detect a
previously running task that's been restored, so that we can trigger the
template `change_mode` if the template is changed, as it will be only with
dynamic secrets.
Currently, if killTask results in the termination of a process before
calling WaitTask, Restart() will incorrectly return a TaskNotFound
error when using the raw_exec driver on Windows.
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.
This PR improves how killing a task is handled. Before the kill function
directly orchestrated the killing and was only valid while the task was
running. The new behavior is to mark the desired state and wait for the
task runner to converge to that state.
For lifecycle operations such as Restart and Kill, the client should not
expect driver plugins to be well behaved and close their waitCh on
context cancelation. Always wait on the passed in context as well as the
waitCh.
