Check in gVisor.

PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 252 insertions, 0 deletions

diff --git a/pkg/metric/metric_test.go b/pkg/metric/metric_test.go
new file mode 100644
index 000000000..7d156e4a5
--- /dev/null
+++ b/pkg/metric/metric_test.go
@@ -0,0 +1,252 @@
+// Copyright 2018 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package metric
+
+import (
+	"testing"
+
+	"github.com/golang/protobuf/proto"
+	"gvisor.googlesource.com/gvisor/pkg/eventchannel"
+	pb "gvisor.googlesource.com/gvisor/pkg/metric/metric_go_proto"
+)
+
+// sliceEmitter implements eventchannel.Emitter by appending all messages to a
+// slice.
+type sliceEmitter []proto.Message
+
+// Emit implements eventchannel.Emitter.Emit.
+func (s *sliceEmitter) Emit(msg proto.Message) (bool, error) {
+	*s = append(*s, msg)
+	return false, nil
+}
+
+// Emit implements eventchannel.Emitter.Close.
+func (s *sliceEmitter) Close() error {
+	return nil
+}
+
+// Reset clears all events in s.
+func (s *sliceEmitter) Reset() {
+	*s = nil
+}
+
+// emitter is the eventchannel.Emitter used for all tests. Package eventchannel
+// doesn't allow removing Emitters, so we must use one global emitter for all
+// test cases.
+var emitter sliceEmitter
+
+func init() {
+	eventchannel.AddEmitter(&emitter)
+}
+
+// reset clears all global state in the metric package.
+func reset() {
+	initialized = false
+	allMetrics = makeMetricSet()
+	emitter.Reset()
+}
+
+const (
+	fooDescription = "Foo!"
+	barDescription = "Bar Baz"
+)
+
+func TestInitialize(t *testing.T) {
+	defer reset()
+
+	_, err := NewUint64Metric("/foo", false, fooDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	_, err = NewUint64Metric("/bar", true, barDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	Initialize()
+
+	if len(emitter) != 1 {
+		t.Fatalf("Initialize emitted %d events want 1", len(emitter))
+	}
+
+	mr, ok := emitter[0].(*pb.MetricRegistration)
+	if !ok {
+		t.Fatalf("emitter %v got %T want pb.MetricRegistration", emitter[0], emitter[0])
+	}
+
+	if len(mr.Metrics) != 2 {
+		t.Errorf("MetricRegistration got %d metrics want 2", len(mr.Metrics))
+	}
+
+	foundFoo := false
+	foundBar := false
+	for _, m := range mr.Metrics {
+		if m.Type != pb.MetricMetadata_UINT64 {
+			t.Errorf("Metadata %+v Type got %v want %v", m, m.Type, pb.MetricMetadata_UINT64)
+		}
+		if !m.Cumulative {
+			t.Errorf("Metadata %+v Cumulative got false want true", m)
+		}
+
+		switch m.Name {
+		case "/foo":
+			foundFoo = true
+			if m.Description != fooDescription {
+				t.Errorf("/foo %+v Description got %q want %q", m, m.Description, fooDescription)
+			}
+			if m.Sync {
+				t.Errorf("/foo %+v Sync got true want false", m)
+			}
+		case "/bar":
+			foundBar = true
+			if m.Description != barDescription {
+				t.Errorf("/bar %+v Description got %q want %q", m, m.Description, barDescription)
+			}
+			if !m.Sync {
+				t.Errorf("/bar %+v Sync got true want false", m)
+			}
+		}
+	}
+
+	if !foundFoo {
+		t.Errorf("/foo not found: %+v", emitter)
+	}
+	if !foundBar {
+		t.Errorf("/bar not found: %+v", emitter)
+	}
+}
+
+func TestDisable(t *testing.T) {
+	defer reset()
+
+	_, err := NewUint64Metric("/foo", false, fooDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	_, err = NewUint64Metric("/bar", true, barDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	Disable()
+
+	if len(emitter) != 1 {
+		t.Fatalf("Initialize emitted %d events want 1", len(emitter))
+	}
+
+	mr, ok := emitter[0].(*pb.MetricRegistration)
+	if !ok {
+		t.Fatalf("emitter %v got %T want pb.MetricRegistration", emitter[0], emitter[0])
+	}
+
+	if len(mr.Metrics) != 0 {
+		t.Errorf("MetricRegistration got %d metrics want 0", len(mr.Metrics))
+	}
+}
+
+func TestEmitMetricUpdate(t *testing.T) {
+	defer reset()
+
+	foo, err := NewUint64Metric("/foo", false, fooDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	_, err = NewUint64Metric("/bar", true, barDescription)
+	if err != nil {
+		t.Fatalf("NewUint64Metric got err %v want nil", err)
+	}
+
+	Initialize()
+
+	// Don't care about the registration metrics.
+	emitter.Reset()
+	EmitMetricUpdate()
+
+	if len(emitter) != 1 {
+		t.Fatalf("EmitMetricUpdate emitted %d events want 1", len(emitter))
+	}
+
+	update, ok := emitter[0].(*pb.MetricUpdate)
+	if !ok {
+		t.Fatalf("emitter %v got %T want pb.MetricUpdate", emitter[0], emitter[0])
+	}
+
+	if len(update.Metrics) != 2 {
+		t.Errorf("MetricUpdate got %d metrics want 2", len(update.Metrics))
+	}
+
+	// Both are included for their initial values.
+	foundFoo := false
+	foundBar := false
+	for _, m := range update.Metrics {
+		switch m.Name {
+		case "/foo":
+			foundFoo = true
+		case "/bar":
+			foundBar = true
+		}
+		uv, ok := m.Value.(*pb.MetricValue_Uint64Value)
+		if !ok {
+			t.Errorf("%+v: value %v got %T want pb.MetricValue_Uint64Value", m, m.Value, m.Value)
+			continue
+		}
+		if uv.Uint64Value != 0 {
+			t.Errorf("%v: Value got %v want 0", m, uv.Uint64Value)
+		}
+	}
+
+	if !foundFoo {
+		t.Errorf("/foo not found: %+v", emitter)
+	}
+	if !foundBar {
+		t.Errorf("/bar not found: %+v", emitter)
+	}
+
+	// Increment foo. Only it is included in the next update.
+	foo.Increment()
+
+	emitter.Reset()
+	EmitMetricUpdate()
+
+	if len(emitter) != 1 {
+		t.Fatalf("EmitMetricUpdate emitted %d events want 1", len(emitter))
+	}
+
+	update, ok = emitter[0].(*pb.MetricUpdate)
+	if !ok {
+		t.Fatalf("emitter %v got %T want pb.MetricUpdate", emitter[0], emitter[0])
+	}
+
+	if len(update.Metrics) != 1 {
+		t.Errorf("MetricUpdate got %d metrics want 1", len(update.Metrics))
+	}
+
+	m := update.Metrics[0]
+
+	if m.Name != "/foo" {
+		t.Errorf("Metric %+v name got %q want '/foo'", m, m.Name)
+	}
+
+	uv, ok := m.Value.(*pb.MetricValue_Uint64Value)
+	if !ok {
+		t.Errorf("%+v: value %v got %T want pb.MetricValue_Uint64Value", m, m.Value, m.Value)
+	}
+	if uv.Uint64Value != 1 {
+		t.Errorf("%v: Value got %v want 1", m, uv.Uint64Value)
+	}
+}