Golang state.ReadState函数代码示例

func (ss *stateSuite) TestCheckpointPreserveCleanStatus(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	chg := st.NewChange("install", "...")
	t := st.NewTask("download", "...")
	chg.AddTask(t)
	t.SetStatus(state.DoneStatus)
	t.SetClean()

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)

	st2.Lock()
	defer st2.Unlock()

	chg2 := st2.Change(chg.ID())
	t2 := st2.Task(t.ID())

	c.Assert(chg2.IsClean(), Equals, true)
	c.Assert(t2.IsClean(), Equals, true)
}

func (ss *stateSuite) TestEmptyTaskAndChangeDataAndCheckpointReadAndSet(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	t1 := st.NewTask("1...", "...")
	t1ID := t1.ID()
	chg := st.NewChange("chg", "...")
	chgID := chg.ID()
	chg.AddTask(t1)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)
	c.Assert(st2, NotNil)

	st2.Lock()
	defer st2.Unlock()

	chg2 := st2.Change(chgID)
	t1_2 := st2.Task(t1ID)
	c.Assert(t1_2, NotNil)

	// no crash
	chg2.Set("c", 1)
	// no crash either
	t1_2.Set("t", 1)
}

func (ss *stateSuite) TestCheckpointPreserveLastIds(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	st.NewChange("install", "...")
	st.NewTask("download", "...")
	st.NewTask("download", "...")

	c.Assert(st.NewLane(), Equals, 1)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)

	st2.Lock()
	defer st2.Unlock()

	c.Assert(st2.NewTask("download", "...").ID(), Equals, "3")
	c.Assert(st2.NewChange("install", "...").ID(), Equals, "2")

	c.Assert(st2.NewLane(), Equals, 2)

}

func loadState(backend state.Backend) (*state.State, error) {
	if !osutil.FileExists(dirs.SnapStateFile) {
		// fail fast, mostly interesting for tests, this dir is setup
		// by the snapd package
		stateDir := filepath.Dir(dirs.SnapStateFile)
		if !osutil.IsDirectory(stateDir) {
			return nil, fmt.Errorf("fatal: directory %q must be present", stateDir)
		}
		s := state.New(backend)
		patch.Init(s)
		return s, nil
	}

	r, err := os.Open(dirs.SnapStateFile)
	if err != nil {
		return nil, fmt.Errorf("cannot read the state file: %s", err)
	}
	defer r.Close()

	s, err := state.ReadState(backend, r)
	if err != nil {
		return nil, err
	}

	// one-shot migrations
	err = patch.Apply(s)
	if err != nil {
		return nil, err
	}
	return s, nil
}

func (ss *stateSuite) TestEmptyStateDataAndCheckpointReadAndSet(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	chg := st.NewChange("install", "summary")
	c.Assert(chg, NotNil)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)
	c.Assert(st2, NotNil)

	st2.Lock()
	defer st2.Unlock()

	// no crash
	st2.Set("a", 1)
}

func (ss *stateSuite) TestReadStateInitsCache(c *C) {
	st, err := state.ReadState(nil, bytes.NewBufferString("{}"))
	c.Assert(err, IsNil)
	st.Lock()
	defer st.Unlock()

	st.Cache("key", "value")
	c.Assert(st.Cached("key"), Equals, "value")
}

func (s *patch4Suite) TestPatch4OnRefreshes(c *C) {
	restorer := patch.MockLevel(4)
	defer restorer()

	r, err := os.Open(dirs.SnapStateFile)
	c.Assert(err, IsNil)
	defer r.Close()
	st, err := state.ReadState(nil, r)
	c.Assert(err, IsNil)

	func() {
		st.Lock()
		defer st.Unlock()

		task := st.Task("16")
		c.Assert(task, NotNil)
		// simulate that the task was running (but the change
		// is not fully done yet)
		task.SetStatus(state.DoneStatus)

		snapsup, err := patch.Patch4TaskSnapSetup(task)
		c.Assert(err, IsNil)
		c.Check(snapsup.Flags.Revert(), Equals, false)

		var had bool
		var idx int
		c.Check(task.Get("had-candidate", &had), IsNil)
		c.Check(had, Equals, false)
		c.Check(task.Get("old-candidate-index", &idx), Equals, state.ErrNoState)
		c.Check(len(task.Change().Tasks()), Equals, 7)
	}()

	// go from patch level 3 -> 4
	err = patch.Apply(st)
	c.Assert(err, IsNil)

	st.Lock()
	defer st.Unlock()

	task := st.Task("16")
	c.Assert(task, NotNil)

	snapsup, err := patch.Patch4TaskSnapSetup(task)
	c.Assert(err, IsNil)
	c.Check(snapsup.Flags.Revert(), Equals, false)

	var had bool
	var idx int
	c.Check(task.Get("had-candidate", &had), Equals, state.ErrNoState)
	c.Check(task.Get("old-candidate-index", &idx), IsNil)
	c.Check(idx, Equals, 1)
	// we added cleanup
	c.Check(len(task.Change().Tasks()), Equals, 7+1)
}

func (s *patch2Suite) TestPatch2(c *C) {
	restorer := patch.MockLevel(2)
	defer restorer()

	r, err := os.Open(dirs.SnapStateFile)
	c.Assert(err, IsNil)
	defer r.Close()
	st, err := state.ReadState(nil, r)
	c.Assert(err, IsNil)

	// go from patch level 1 -> 2
	err = patch.Apply(st)
	c.Assert(err, IsNil)

	st.Lock()
	defer st.Unlock()

	// our mocks are correct
	c.Assert(st.Changes(), HasLen, 2)
	c.Assert(st.Tasks(), HasLen, 2)

	var snapsup snapstate.SnapSetup
	// transition of:
	// - SnapSetup.{Name,Revision} -> SnapSetup.SideInfo.{RealName,Revision}
	t := st.Task("1")
	err = t.Get("snap-setup", &snapsup)
	c.Assert(err, IsNil)
	c.Assert(snapsup.SideInfo, DeepEquals, &snap.SideInfo{
		RealName: "foo",
		Revision: snap.R("x3"),
	})

	// transition of:
	// - SnapState.Sequence is backfilled with "RealName" (if missing)
	var snapst snapstate.SnapState
	err = snapstate.Get(st, "foo", &snapst)
	c.Assert(err, IsNil)
	c.Check(snapst.Sequence[0].RealName, Equals, "foo")
	c.Check(snapst.Sequence[1].RealName, Equals, "foo")

	// transition of:
	// - Candidate for "bar" -> tasks SnapSetup.SideInfo
	t = st.Task("2")
	err = t.Get("snap-setup", &snapsup)
	c.Assert(err, IsNil)
	c.Assert(snapsup.SideInfo, DeepEquals, &snap.SideInfo{
		RealName: "bar",
		Revision: snap.R("x1"),
	})

	// FIXME: bar is now empty and should no longer be there?
	err = snapstate.Get(st, "bar", &snapst)
	c.Assert(err, IsNil)
}

// This test simulates a link-snap task that is scheduled but has not
// run yet. It has no "had-candidate" data set yet.
func (s *patch4Suite) TestPatch4OnRefreshesNoHadCandidateYet(c *C) {
	restorer := patch.MockLevel(4)
	defer restorer()

	r, err := os.Open(dirs.SnapStateFile)
	c.Assert(err, IsNil)
	defer r.Close()
	st, err := state.ReadState(nil, r)
	c.Assert(err, IsNil)

	func() {
		st.Lock()
		defer st.Unlock()

		task := st.Task("16")
		c.Assert(task, NotNil)
		// its ready to run but has not run yet
		task.Clear("had-candidate")
		task.SetStatus(state.DoStatus)

		ss, err := snapstate.TaskSnapSetup(task)
		c.Assert(err, IsNil)
		c.Check(ss.Flags.Revert(), Equals, false)

		var had bool
		var idx int
		c.Check(task.Get("had-candidate", &had), Equals, state.ErrNoState)
		c.Check(task.Get("old-candidate-index", &idx), Equals, state.ErrNoState)
		c.Check(len(task.Change().Tasks()), Equals, 7)
	}()

	// go from patch level 3 -> 4
	err = patch.Apply(st)
	c.Assert(err, IsNil)

	st.Lock()
	defer st.Unlock()

	task := st.Task("16")
	c.Assert(task, NotNil)

	ss, err := snapstate.TaskSnapSetup(task)
	c.Assert(err, IsNil)
	c.Check(ss.Flags.Revert(), Equals, false)

	var had bool
	var idx int
	c.Check(task.Get("had-candidate", &had), Equals, state.ErrNoState)
	c.Check(task.Get("old-candidate-index", &idx), IsNil)
	c.Check(idx, Equals, 1)
	// we added cleanup
	c.Check(len(task.Change().Tasks()), Equals, 7+1)
}

func (ss *stateSuite) TestNewChangeAndCheckpoint(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	chg := st.NewChange("install", "summary")
	c.Assert(chg, NotNil)
	chgID := chg.ID()
	chg.Set("a", 1)
	chg.SetStatus(state.ErrorStatus)

	spawnTime := chg.SpawnTime()
	readyTime := chg.ReadyTime()

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)
	c.Assert(st2, NotNil)

	st2.Lock()
	defer st2.Unlock()

	chgs := st2.Changes()

	c.Assert(chgs, HasLen, 1)

	chg0 := chgs[0]
	c.Check(chg0.ID(), Equals, chgID)
	c.Check(chg0.Kind(), Equals, "install")
	c.Check(chg0.Summary(), Equals, "summary")
	c.Check(chg0.SpawnTime().Equal(spawnTime), Equals, true)
	c.Check(chg0.ReadyTime().Equal(readyTime), Equals, true)

	var v int
	err = chg0.Get("a", &v)
	c.Check(err, IsNil)
	c.Check(v, Equals, 1)

	c.Check(chg0.Status(), Equals, state.ErrorStatus)

	select {
	case <-chg0.Ready():
	default:
		c.Errorf("Change didn't preserve Ready channel closed after deserialization")
	}
}

func (s *patch1Suite) TestPatch1(c *C) {
	restore := patch.MockReadInfo(s.readInfo)
	defer restore()

	r, err := os.Open(dirs.SnapStateFile)
	c.Assert(err, IsNil)
	defer r.Close()
	st, err := state.ReadState(nil, r)
	c.Assert(err, IsNil)

	// go from patch-level 0 to patch-level 1
	restorer := patch.MockLevel(1)
	defer restorer()

	err = patch.Apply(st)
	c.Assert(err, IsNil)

	st.Lock()
	defer st.Unlock()

	expected := []struct {
		name string
		typ  snap.Type
		cur  snap.Revision
	}{
		{"foo", snap.TypeApp, snap.R(22)},
		{"core", snap.TypeOS, snap.R(111)},
		{"borken", snap.TypeApp, snap.R(-2)},
		{"wip", "", snap.R(0)},
	}

	for _, exp := range expected {
		var snapst snapstate.SnapState
		err := snapstate.Get(st, exp.name, &snapst)
		c.Assert(err, IsNil)
		c.Check(snap.Type(snapst.SnapType), Equals, exp.typ)
		c.Check(snapst.Current, Equals, exp.cur)
	}

	// ensure we only moved forward to patch-level 1
	var patchLevel int
	err = st.Get("patch-level", &patchLevel)
	c.Assert(err, IsNil)
	c.Assert(patchLevel, Equals, 1)
}

func (ss *stateSuite) TestImplicitCheckpointAndRead(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	st.Set("v", 1)
	mSt1 := &mgrState1{A: "foo"}
	st.Set("mgr1", mSt1)
	mSt2 := &mgrState2{C: &Count2{B: 42}}
	st.Set("mgr2", mSt2)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)
	c.Assert(st2.Modified(), Equals, false)

	st2.Lock()
	defer st2.Unlock()

	var v int
	err = st2.Get("v", &v)
	c.Assert(err, IsNil)
	c.Check(v, Equals, 1)

	var mSt1B mgrState1
	err = st2.Get("mgr1", &mSt1B)
	c.Assert(err, IsNil)
	c.Check(&mSt1B, DeepEquals, mSt1)

	var mSt2B mgrState2
	err = st2.Get("mgr2", &mSt2B)
	c.Assert(err, IsNil)
	c.Check(&mSt2B, DeepEquals, mSt2)
}

func (ss *stateSuite) TestNewChangeAndCheckpointTaskDerivedStatus(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	chg := st.NewChange("install", "summary")
	c.Assert(chg, NotNil)
	chgID := chg.ID()

	t1 := st.NewTask("download", "1...")
	t1.SetStatus(state.DoneStatus)
	chg.AddTask(t1)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)
	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)

	st2.Lock()
	defer st2.Unlock()

	chgs := st2.Changes()

	c.Assert(chgs, HasLen, 1)

	chg0 := chgs[0]
	c.Check(chg0.ID(), Equals, chgID)
	c.Check(chg0.Status(), Equals, state.DoneStatus)

	select {
	case <-chg0.Ready():
	default:
		c.Errorf("Change didn't preserve Ready channel closed after deserialization")
	}
}

func (ss *stateSuite) TestNewTaskAndCheckpoint(c *C) {
	b := new(fakeStateBackend)
	st := state.New(b)
	st.Lock()

	chg := st.NewChange("install", "summary")
	c.Assert(chg, NotNil)

	t1 := st.NewTask("download", "1...")
	chg.AddTask(t1)
	t1ID := t1.ID()
	t1.Set("a", 1)
	t1.SetStatus(state.DoneStatus)
	t1.SetProgress("snap", 5, 10)
	t1.JoinLane(42)
	t1.JoinLane(43)

	t2 := st.NewTask("inst", "2...")
	chg.AddTask(t2)
	t2ID := t2.ID()
	t2.WaitFor(t1)
	schedule := time.Now().Add(time.Hour)
	t2.At(schedule)

	// implicit checkpoint
	st.Unlock()

	c.Assert(b.checkpoints, HasLen, 1)

	buf := bytes.NewBuffer(b.checkpoints[0])

	st2, err := state.ReadState(nil, buf)
	c.Assert(err, IsNil)
	c.Assert(st2, NotNil)

	st2.Lock()
	defer st2.Unlock()

	chgs := st2.Changes()
	c.Assert(chgs, HasLen, 1)
	chg0 := chgs[0]

	tasks0 := make(map[string]*state.Task)
	for _, t := range chg0.Tasks() {
		tasks0[t.ID()] = t
	}
	c.Assert(tasks0, HasLen, 2)

	task0_1 := tasks0[t1ID]
	c.Check(task0_1.ID(), Equals, t1ID)
	c.Check(task0_1.Kind(), Equals, "download")
	c.Check(task0_1.Summary(), Equals, "1...")
	c.Check(task0_1.Change(), Equals, chg0)

	var v int
	err = task0_1.Get("a", &v)
	c.Check(v, Equals, 1)

	c.Check(task0_1.Status(), Equals, state.DoneStatus)

	_, cur, tot := task0_1.Progress()
	c.Check(cur, Equals, 5)
	c.Check(tot, Equals, 10)

	c.Assert(task0_1.Lanes(), DeepEquals, []int{42, 43})

	task0_2 := tasks0[t2ID]
	c.Check(task0_2.WaitTasks(), DeepEquals, []*state.Task{task0_1})

	c.Check(task0_1.HaltTasks(), DeepEquals, []*state.Task{task0_2})

	tasks2 := make(map[string]*state.Task)
	for _, t := range st2.Tasks() {
		tasks2[t.ID()] = t
	}
	c.Assert(tasks2, HasLen, 2)

	c.Check(task0_1.AtTime().IsZero(), Equals, true)
	c.Check(task0_2.AtTime().Equal(schedule), Equals, true)
}

//.........这里部分代码省略.........
	sha3_384, size, err := asserts.SnapFileSHA3_384(fooSnapFile)
	c.Assert(err, IsNil)

	snapRevFoo, err := s.storeSigning.Sign(asserts.SnapRevisionType, map[string]interface{}{
		"snap-sha3-384": sha3_384,
		"snap-size":     fmt.Sprintf("%d", size),
		"snap-id":       "foosnapidsnapid",
		"developer-id":  "developerid",
		"snap-revision": "128",
		"timestamp":     time.Now().UTC().Format(time.RFC3339),
	}, nil, "")
	c.Assert(err, IsNil)

	writeAssertionsToFile("foo.asserts", []asserts.Assertion{devAcct, snapRevFoo, snapDeclFoo})

	snapDeclBar, err := s.storeSigning.Sign(asserts.SnapDeclarationType, map[string]interface{}{
		"series":       "16",
		"snap-id":      "barsnapidsnapid",
		"publisher-id": "developerid",
		"snap-name":    "bar",
		"timestamp":    time.Now().UTC().Format(time.RFC3339),
	}, nil, "")
	c.Assert(err, IsNil)

	sha3_384, size, err = asserts.SnapFileSHA3_384(barSnapFile)
	c.Assert(err, IsNil)

	snapRevBar, err := s.storeSigning.Sign(asserts.SnapRevisionType, map[string]interface{}{
		"snap-sha3-384": sha3_384,
		"snap-size":     fmt.Sprintf("%d", size),
		"snap-id":       "barsnapidsnapid",
		"developer-id":  "developerid",
		"snap-revision": "65",
		"timestamp":     time.Now().UTC().Format(time.RFC3339),
	}, nil, "")
	c.Assert(err, IsNil)

	writeAssertionsToFile("bar.asserts", []asserts.Assertion{devAcct, snapDeclBar, snapRevBar})

	// add a model assertion and its chain
	assertsChain := s.makeModelAssertionChain(c)
	writeAssertionsToFile("model.asserts", assertsChain)

	// create a seed.yaml
	content := []byte(fmt.Sprintf(`
snaps:
 - name: foo
   file: %s
 - name: bar
   file: %s
`, filepath.Base(fooSnapFile), filepath.Base(barSnapFile)))
	err = ioutil.WriteFile(filepath.Join(dirs.SnapSeedDir, "seed.yaml"), content, 0644)
	c.Assert(err, IsNil)

	// run the firstboot stuff
	st := s.overlord.State()
	st.Lock()
	defer st.Unlock()

	tsAll, err := devicestate.PopulateStateFromSeedImpl(st)
	c.Assert(err, IsNil)
	chg := st.NewChange("run-it", "run the populate from seed changes")
	for _, ts := range tsAll {
		chg.AddAll(ts)
	}
	c.Assert(st.Changes(), HasLen, 1)

	st.Unlock()
	s.overlord.Settle()
	st.Lock()
	c.Assert(chg.Err(), IsNil)

	// and check the snap got correctly installed
	c.Check(osutil.FileExists(filepath.Join(dirs.SnapMountDir, "foo", "128", "meta", "snap.yaml")), Equals, true)

	// and check the snap got correctly installed
	c.Check(osutil.FileExists(filepath.Join(dirs.SnapMountDir, "bar", "65", "meta", "snap.yaml")), Equals, true)

	// verify
	r, err := os.Open(dirs.SnapStateFile)
	c.Assert(err, IsNil)
	state, err := state.ReadState(nil, r)
	c.Assert(err, IsNil)

	state.Lock()
	defer state.Unlock()
	// check foo
	info, err := snapstate.CurrentInfo(state, "foo")
	c.Assert(err, IsNil)
	c.Assert(info.SnapID, Equals, "foosnapidsnapid")
	c.Assert(info.Revision, Equals, snap.R(128))
	c.Assert(info.DeveloperID, Equals, "developerid")

	// check bar
	info, err = snapstate.CurrentInfo(state, "bar")
	c.Assert(err, IsNil)
	c.Assert(info.SnapID, Equals, "barsnapidsnapid")
	c.Assert(info.Revision, Equals, snap.R(65))
	c.Assert(info.DeveloperID, Equals, "developerid")
}