Esempio n. 1
0
// TestTrivialWorkUnitFlow tests work unit creation, deletion, and existence.
func (s *Suite) TestTrivialWorkUnitFlow(c *check.C) {
	var (
		count int
		err   error
		spec  coordinate.WorkSpec
		unit  coordinate.WorkUnit
		units map[string]coordinate.WorkUnit
	)

	spec, err = s.Namespace.SetWorkSpec(map[string]interface{}{
		"name":   "spec",
		"min_gb": 1,
	})
	c.Assert(err, check.IsNil)

	unit, err = spec.AddWorkUnit("unit", map[string]interface{}{}, 0)
	c.Assert(err, check.IsNil)
	c.Check(unit.Name(), check.Equals, "unit")
	c.Check(unit.WorkSpec().Name(), check.Equals, "spec")

	unit, err = spec.WorkUnit("unit")
	c.Assert(err, check.IsNil)
	c.Check(unit.Name(), check.Equals, "unit")
	c.Check(unit.WorkSpec().Name(), check.Equals, "spec")

	units, err = spec.WorkUnits(coordinate.WorkUnitQuery{})
	c.Assert(err, check.IsNil)
	c.Check(units, check.HasLen, 1)
	c.Check(units["unit"], check.NotNil)
	c.Check(units["unit"].Name(), check.Equals, "unit")
	c.Check(units["unit"].WorkSpec().Name(), check.Equals, "spec")

	count, err = spec.DeleteWorkUnits(coordinate.WorkUnitQuery{})
	c.Assert(err, check.IsNil)
	c.Check(count, check.Equals, 1)

	unit, err = spec.WorkUnit("unit")
	c.Assert(err, check.IsNil)
	c.Check(unit, check.IsNil)

	units, err = spec.WorkUnits(coordinate.WorkUnitQuery{})
	c.Assert(err, check.IsNil)
	c.Check(units, check.HasLen, 0)
}
Esempio n. 2
0
// UpdateWorkUnit causes some state change in a work unit.  If the
// work unit is pending, this is the principal interface to complete
// or renew it; if it is already complete this can cause it to be
// retried.
func (jobs *JobServer) UpdateWorkUnit(
	workSpecName string,
	workUnitKey string,
	options map[string]interface{},
) (bool, string, error) {
	// Note that in several corner cases, the behavior of this as
	// written disagrees with Python coordinated's:
	//
	// * If neither "lease_time" nor "status" is specified,
	//   Python coordinated immediately returns False without
	//   checking if workUnitKey is valid
	//
	// * Python coordinated allows arbitrary status changes,
	//   including AVAILABLE -> FINISHED
	//
	// * This openly ignores "worker_id", as distinct from Python
	//   coordinated, which logs an obscure warning and changes it,
	//   but only on a renew
	var (
		attempt    coordinate.Attempt
		changed    bool
		err        error
		status     coordinate.AttemptStatus
		uwuOptions UpdateWorkUnitOptions
		workSpec   coordinate.WorkSpec
		workUnit   coordinate.WorkUnit
	)
	err = decode(&uwuOptions, options)
	if err == nil {
		workSpec, err = jobs.Namespace.WorkSpec(workSpecName)
	}
	if err == nil {
		workUnit, err = workSpec.WorkUnit(workUnitKey)
	}
	if err == nil {
		if workUnit == nil {
			return false, fmt.Sprintf("no such work unit key=%v", workUnitKey), nil
		}
	}
	if err == nil {
		attempt, err = workUnit.ActiveAttempt()
	}
	if err == nil && attempt != nil {
		status, err = attempt.Status()
	}
	if err == nil && attempt != nil {
		if status == coordinate.Expired || status == coordinate.Retryable {
			// The Python Coordinate API sees both of these
			// statuses as "available", and we want to fall
			// into the next block.
			attempt = nil
		}
	}
	if err == nil && attempt == nil {
		// Caller is trying to manipulate an AVAILABLE work
		// unit.  Cowardly refuse to start a new attempt on
		// their behalf, or to update the persistent work unit
		// data this way.  (In theory there's no reason we
		// *couldn't* do either, though I'm not aware of any
		// callers that do; add_work_unit will replace
		// existing work units and is the more typical way to
		// refresh data.)
		err = errors.New("update_work_unit will not adjust an available work unit")
	}
	if err == nil {
		switch status {
		case coordinate.Pending:
			changed = true // or there's an error
			switch uwuOptions.Status {
			case 0, Pending:
				err = uwuRenew(attempt, uwuOptions)
			case Available:
				err = attempt.Expire(uwuOptions.Data)
			case Finished:
				err = attempt.Finish(uwuOptions.Data)
			case Failed:
				err = attempt.Fail(uwuOptions.Data)
			default:
				err = errors.New("update_work_unit invalid status")
			}
		case coordinate.Expired:
			err = errors.New("update_work_unit logic error, trying to refresh expired unit")
		case coordinate.Finished:
			switch uwuOptions.Status {
			case 0, Finished:
				changed = false // no-op
			case Available:
				err = workUnit.ClearActiveAttempt()
				changed = true
			case Failed:
				changed = false // see below
			default:
				err = errors.New("update_work_unit cannot change finished unit")
			}
		case coordinate.Failed:
			switch uwuOptions.Status {
			case 0, Failed:
				changed = false // no-op
			case Available: // "retry"
				err = workUnit.ClearActiveAttempt()
				changed = true
			case Finished:
				// The Python worker, with two separate
				// processes, has a race wherein there
				// could be 15 seconds to go, the parent
				// kills off the child, and the child
				// finishes successfully, all at the same
				// time.  In that case the successful
				// finish should win.
				err = attempt.Finish(nil)
				changed = true
			default:
				err = errors.New("update_work_unit cannot change failed unit")
			}
		case coordinate.Retryable:
			err = errors.New("update_work_unit logic error, trying to refresh retryable unit")
		default:
			err = fmt.Errorf("update_work_unit invalid attempt status %+v", status)
		}
	}
	return changed && err == nil, "", err
}