Golang Iterator.Optimize方法代码示例

func (wk *worker) runIterator(it graph.Iterator) {
	if wk.wantShape() {
		iterator.OutputQueryShapeForIterator(it, wk.qs, wk.shape)
		return
	}
	it, _ = it.Optimize()
	if clog.V(2) {
		b, err := json.MarshalIndent(it.Describe(), "", "  ")
		if err != nil {
			clog.Infof("failed to format description: %v", err)
		} else {
			clog.Infof("%s", b)
		}
	}
	for {
		select {
		case <-wk.kill:
			return
		default:
		}
		if !graph.Next(it) {
			break
		}
		tags := make(map[string]graph.Value)
		it.TagResults(tags)
		if !wk.send(&Result{actualResults: tags}) {
			break
		}
		for it.NextPath() {
			select {
			case <-wk.kill:
				return
			default:
			}
			tags := make(map[string]graph.Value)
			it.TagResults(tags)
			if !wk.send(&Result{actualResults: tags}) {
				break
			}
		}
	}
	if clog.V(2) {
		bytes, _ := json.MarshalIndent(graph.DumpStats(it), "", "  ")
		clog.Infof(string(bytes))
	}
	it.Close()
}

func (wk *worker) runIteratorWithCallback(it graph.Iterator, callback otto.Value, this otto.FunctionCall, limit int) {
	n := 0
	it, _ = it.Optimize()
	if clog.V(2) {
		b, err := json.MarshalIndent(it.Describe(), "", "  ")
		if err != nil {
			clog.Infof("failed to format description: %v", err)
		} else {
			clog.Infof("%s", b)
		}
	}
	for {
		select {
		case <-wk.kill:
			return
		default:
		}
		if !graph.Next(it) {
			break
		}
		tags := make(map[string]graph.Value)
		it.TagResults(tags)
		val, _ := this.Otto.ToValue(wk.tagsToValueMap(tags))
		val, _ = callback.Call(this.This, val)
		n++
		if limit >= 0 && n >= limit {
			break
		}
		for it.NextPath() {
			select {
			case <-wk.kill:
				return
			default:
			}
			tags := make(map[string]graph.Value)
			it.TagResults(tags)
			val, _ := this.Otto.ToValue(wk.tagsToValueMap(tags))
			val, _ = callback.Call(this.This, val)
			n++
			if limit >= 0 && n >= limit {
				break
			}
		}
	}
	it.Close()
}

func (wk *worker) runIteratorToArrayNoTags(it graph.Iterator, limit int) []string {
	output := make([]string, 0)
	n := 0
	it, _ = it.Optimize()
	for {
		select {
		case <-wk.kill:
			return nil
		default:
		}
		if !graph.Next(it) {
			break
		}
		output = append(output, wk.qs.NameOf(it.Result()))
		n++
		if limit >= 0 && n >= limit {
			break
		}
	}
	it.Close()
	return output
}

func (wk *worker) runIteratorToArray(it graph.Iterator, limit int) []map[string]string {
	output := make([]map[string]string, 0)
	n := 0
	it, _ = it.Optimize()
	for {
		select {
		case <-wk.kill:
			return nil
		default:
		}
		if !graph.Next(it) {
			break
		}
		tags := make(map[string]graph.Value)
		it.TagResults(tags)
		output = append(output, wk.tagsToValueMap(tags))
		n++
		if limit >= 0 && n >= limit {
			break
		}
		for it.NextPath() {
			select {
			case <-wk.kill:
				return nil
			default:
			}
			tags := make(map[string]graph.Value)
			it.TagResults(tags)
			output = append(output, wk.tagsToValueMap(tags))
			n++
			if limit >= 0 && n >= limit {
				break
			}
		}
	}
	it.Close()
	return output
}

func TestIterator(t *testing.T) {
	tmpDir, err := ioutil.TempDir(os.TempDir(), "cayley_test")
	if err != nil {
		t.Fatalf("Could not create working directory: %v", err)
	}
	defer os.RemoveAll(tmpDir)
	t.Log(tmpDir)

	err = createNewLevelDB(tmpDir, nil)
	if err != nil {
		t.Fatal("Failed to create LevelDB database.")
	}

	qs, err := newQuadStore(tmpDir, nil)
	if qs == nil || err != nil {
		t.Error("Failed to create leveldb QuadStore.")
	}

	w, _ := writer.NewSingleReplication(qs, nil)
	w.AddQuadSet(makeQuadSet())
	var it graph.Iterator

	it = qs.NodesAllIterator()
	if it == nil {
		t.Fatal("Got nil iterator.")
	}

	size, exact := it.Size()
	if size <= 0 || size >= 20 {
		t.Errorf("Unexpected size, got:%d expect:(0, 20)", size)
	}
	if exact {
		t.Errorf("Got unexpected exact result.")
	}
	if typ := it.Type(); typ != graph.All {
		t.Errorf("Unexpected iterator type, got:%v expect:%v", typ, graph.All)
	}
	optIt, changed := it.Optimize()
	if changed || optIt != it {
		t.Errorf("Optimize unexpectedly changed iterator.")
	}

	expect := []string{
		"A",
		"B",
		"C",
		"D",
		"E",
		"F",
		"G",
		"follows",
		"status",
		"cool",
		"status_graph",
	}
	sort.Strings(expect)
	for i := 0; i < 2; i++ {
		got := iteratedNames(qs, it)
		sort.Strings(got)
		if !reflect.DeepEqual(got, expect) {
			t.Errorf("Unexpected iterated result on repeat %d, got:%v expect:%v", i, got, expect)
		}
		it.Reset()
	}

	for _, pq := range expect {
		if !it.Contains(qs.ValueOf(pq)) {
			t.Errorf("Failed to find and check %q correctly", pq)
		}
	}
	// FIXME(kortschak) Why does this fail?
	/*
		for _, pq := range []string{"baller"} {
			if it.Contains(qs.ValueOf(pq)) {
				t.Errorf("Failed to check %q correctly", pq)
			}
		}
	*/
	it.Reset()

	it = qs.QuadsAllIterator()
	graph.Next(it)
	q := qs.Quad(it.Result())
	set := makeQuadSet()
	var ok bool
	for _, t := range set {
		if t.String() == q.String() {
			ok = true
			break
		}
	}
	if !ok {
		t.Errorf("Failed to find %q during iteration, got:%q", q, set)
	}

	qs.Close()
}

func TestIterator(t testing.TB, gen DatabaseFunc) {
	qs, opts, closer := gen(t)
	defer closer()

	MakeWriter(t, qs, opts, MakeQuadSet()...)

	var it graph.Iterator

	it = qs.NodesAllIterator()
	require.NotNil(t, it)

	size, _ := it.Size()
	require.True(t, size > 0 && size < 20, "Unexpected size")
	// TODO: leveldb had this test
	//if exact {
	//	t.Errorf("Got unexpected exact result.")
	//}
	require.Equal(t, graph.All, it.Type(), "Unexpected iterator type")

	optIt, changed := it.Optimize()
	require.True(t, !changed && optIt == it, "Optimize unexpectedly changed iterator: %v, %T", changed, optIt)

	expect := []string{
		"A",
		"B",
		"C",
		"D",
		"E",
		"F",
		"G",
		"follows",
		"status",
		"cool",
		"status_graph",
	}
	sort.Strings(expect)
	for i := 0; i < 2; i++ {
		got := IteratedRawStrings(t, qs, it)
		sort.Strings(got)
		require.Equal(t, expect, got, "Unexpected iterated result on repeat %d", i)
		it.Reset()
	}

	for _, pq := range expect {
		require.True(t, it.Contains(qs.ValueOf(quad.Raw(pq))), "Failed to find and check %q correctly", pq)

	}
	// FIXME(kortschak) Why does this fail?
	/*
		for _, pq := range []string{"baller"} {
			if it.Contains(qs.ValueOf(pq)) {
				t.Errorf("Failed to check %q correctly", pq)
			}
		}
	*/
	it.Reset()

	it = qs.QuadsAllIterator()
	optIt, changed = it.Optimize()
	require.True(t, !changed && optIt == it, "Optimize unexpectedly changed iterator: %v, %T", changed, optIt)

	require.True(t, it.Next())

	q := qs.Quad(it.Result())
	require.Nil(t, it.Err())
	require.True(t, q.IsValid(), "Invalid quad returned: %q", q)
	set := MakeQuadSet()
	var ok bool
	for _, e := range set {
		if e.String() == q.String() {
			ok = true
			break
		}
	}
	require.True(t, ok, "Failed to find %q during iteration, got:%q", q, set)
}