Golang NewWatcher Examples

Example #1

File: state.go Project: hivetech/judo.legacy

func (st *State) Watch() *multiwatcher.Watcher {
	st.mu.Lock()
	if st.allManager == nil {
		st.allManager = multiwatcher.NewStoreManager(newAllWatcherStateBacking(st))
	}
	st.mu.Unlock()
	return multiwatcher.NewWatcher(st.allManager)
}

Example #2

File: megawatcher_internal_test.go Project: hivetech/judo.legacy

// StateWatcher tests the integration of the state watcher
// with the state-based backing. Most of the logic is tested elsewhere -
// this just tests end-to-end.
func (s *storeManagerStateSuite) TestStateWatcher(c *C) {
	m0, err := s.State.AddMachine("series", JobManageEnviron)
	c.Assert(err, IsNil)
	c.Assert(m0.Id(), Equals, "0")

	m1, err := s.State.AddMachine("series", JobHostUnits)
	c.Assert(err, IsNil)
	c.Assert(m1.Id(), Equals, "1")

	b := newAllWatcherStateBacking(s.State)
	aw := multiwatcher.NewStoreManager(b)
	defer aw.Stop()
	w := multiwatcher.NewWatcher(aw)
	s.State.StartSync()
	checkNext(c, w, b, []params.Delta{{
		Entity: &params.MachineInfo{
			Id:     "0",
			Status: params.StatusPending,
		},
	}, {
		Entity: &params.MachineInfo{
			Id:     "1",
			Status: params.StatusPending,
		},
	}}, "")

	// Make some changes to the state.
	err = m0.SetProvisioned("i-0", "bootstrap_nonce", nil)
	c.Assert(err, IsNil)
	err = m1.Destroy()
	c.Assert(err, IsNil)
	err = m1.EnsureDead()
	c.Assert(err, IsNil)
	err = m1.Remove()
	c.Assert(err, IsNil)
	m2, err := s.State.AddMachine("series", JobManageEnviron)
	c.Assert(err, IsNil)
	c.Assert(m2.Id(), Equals, "2")
	s.State.StartSync()

	// Check that we see the changes happen within a
	// reasonable time.
	var deltas []params.Delta
	for {
		d, err := getNext(c, w, 100*time.Millisecond)
		if err == errTimeout {
			break
		}
		c.Assert(err, IsNil)
		deltas = append(deltas, d...)
	}
	checkDeltasEqual(c, b, deltas, []params.Delta{{
		Removed: true,
		Entity: &params.MachineInfo{
			Id:     "1",
			Status: params.StatusPending,
		},
	}, {
		Entity: &params.MachineInfo{
			Id:     "2",
			Status: params.StatusPending,
		},
	}, {
		Entity: &params.MachineInfo{
			Id:         "0",
			InstanceId: "i-0",
			Status:     params.StatusPending,
		},
	}})

	err = w.Stop()
	c.Assert(err, IsNil)

	_, err = w.Next()
	c.Assert(err, ErrorMatches, "state watcher was stopped")
}