Initial commit of host metrics load scraper (#974)

receiver/hostmetricsreceiver/config_test.go

@@ -28,6 +28,7 @@ import (
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/cpuscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/diskscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/filesystemscraper"
+	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/loadscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/memoryscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/networkscraper"
 )
@@ -63,6 +64,7 @@ func TestLoadConfig(t *testing.T) {
 			Scrapers: map[string]internal.Config{
 				cpuscraper.TypeStr:        &cpuscraper.Config{ReportPerCPU: true},
 				diskscraper.TypeStr:       &diskscraper.Config{},
+				loadscraper.TypeStr:       &loadscraper.Config{},
 				filesystemscraper.TypeStr: &filesystemscraper.Config{},
 				memoryscraper.TypeStr:     &memoryscraper.Config{},
 				networkscraper.TypeStr:    &networkscraper.Config{},

receiver/hostmetricsreceiver/example_config.yaml

@@ -7,7 +7,7 @@ receivers:
     collection_interval: 1m
     scrapers:
       cpu:
-        report_per_cpu: false
+      load:
       memory:
       disk:
       filesystem:

receiver/hostmetricsreceiver/factory.go

@@ -30,6 +30,7 @@ import (
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/cpuscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/diskscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/filesystemscraper"
+	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/loadscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/memoryscraper"
 	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/scraper/networkscraper"
 )
@@ -53,6 +54,7 @@ func NewFactory() *Factory {
 		scraperFactories: map[string]internal.Factory{
 			cpuscraper.TypeStr:        &cpuscraper.Factory{},
 			diskscraper.TypeStr:       &diskscraper.Factory{},
+			loadscraper.TypeStr:       &loadscraper.Factory{},
 			filesystemscraper.TypeStr: &filesystemscraper.Factory{},
 			memoryscraper.TypeStr:     &memoryscraper.Factory{},
 			networkscraper.TypeStr:    &networkscraper.Factory{},

receiver/hostmetricsreceiver/internal/scraper/loadscraper/config.go

@@ -0,0 +1,22 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import "go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal"
+
+// Config relating to Load Metric Scraper.
+type Config struct {
+	internal.ConfigSettings `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/factory.go

@@ -0,0 +1,49 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import (
+	"context"
+
+	"go.uber.org/zap"
+
+	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal"
+)
+
+// This file implements Factory for Load scraper.
+
+const (
+	// The value of "type" key in configuration.
+	TypeStr = "load"
+)
+
+// Factory is the Factory for scraper.
+type Factory struct {
+}
+
+// CreateDefaultConfig creates the default configuration for the Scraper.
+func (f *Factory) CreateDefaultConfig() internal.Config {
+	return &Config{}
+}
+
+// CreateMetricsScraper creates a scraper based on provided config.
+func (f *Factory) CreateMetricsScraper(
+	ctx context.Context,
+	logger *zap.Logger,
+	config internal.Config,
+) (internal.Scraper, error) {
+	cfg := config.(*Config)
+	return newLoadScraper(ctx, logger, cfg), nil
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/factory_test.go

@@ -0,0 +1,39 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.uber.org/zap"
+)
+
+func TestCreateDefaultConfig(t *testing.T) {
+	factory := &Factory{}
+	cfg := factory.CreateDefaultConfig()
+	assert.IsType(t, &Config{}, cfg)
+}
+
+func TestCreateMetricsScraper(t *testing.T) {
+	factory := &Factory{}
+	cfg := &Config{}
+
+	scraper, err := factory.CreateMetricsScraper(context.Background(), zap.NewNop(), cfg)
+
+	assert.NoError(t, err)
+	assert.NotNil(t, scraper)
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/load_constants.go

@@ -0,0 +1,57 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import (
+	"go.opentelemetry.io/collector/consumer/pdata"
+)
+
+// load metric constants
+
+var metric1MLoadDescriptor = createMetric1MLoadDescriptor()
+
+func createMetric1MLoadDescriptor() pdata.MetricDescriptor {
+	descriptor := pdata.NewMetricDescriptor()
+	descriptor.InitEmpty()
+	descriptor.SetName("host/load/1m")
+	descriptor.SetDescription("Average CPU Load over 1 minute.")
+	descriptor.SetUnit("1")
+	descriptor.SetType(pdata.MetricTypeGaugeDouble)
+	return descriptor
+}
+
+var metric5MLoadDescriptor = createMetric5MLoadDescriptor()
+
+func createMetric5MLoadDescriptor() pdata.MetricDescriptor {
+	descriptor := pdata.NewMetricDescriptor()
+	descriptor.InitEmpty()
+	descriptor.SetName("host/load/5m")
+	descriptor.SetDescription("Average CPU Load over 5 minutes.")
+	descriptor.SetUnit("1")
+	descriptor.SetType(pdata.MetricTypeGaugeDouble)
+	return descriptor
+}
+
+var metric15MLoadDescriptor = createMetric15MLoadDescriptor()
+
+func createMetric15MLoadDescriptor() pdata.MetricDescriptor {
+	descriptor := pdata.NewMetricDescriptor()
+	descriptor.InitEmpty()
+	descriptor.SetName("host/load/15m")
+	descriptor.SetDescription("Average CPU Load over 15 minutes.")
+	descriptor.SetUnit("1")
+	descriptor.SetType(pdata.MetricTypeGaugeDouble)
+	return descriptor
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/load_scraper.go

@@ -0,0 +1,75 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import (
+	"context"
+	"time"
+
+	"go.opencensus.io/trace"
+	"go.uber.org/zap"
+
+	"go.opentelemetry.io/collector/consumer/pdata"
+)
+
+// scraper for Load Metrics
+type scraper struct {
+	logger *zap.Logger
+	config *Config
+}
+
+// newLoadScraper creates a set of Load related metrics
+func newLoadScraper(_ context.Context, logger *zap.Logger, cfg *Config) *scraper {
+	return &scraper{logger: logger, config: cfg}
+}
+
+// Initialize
+func (s *scraper) Initialize(ctx context.Context) error {
+	return startSampling(ctx, s.logger)
+}
+
+// Close
+func (s *scraper) Close(ctx context.Context) error {
+	return stopSampling(ctx)
+}
+
+// ScrapeMetrics
+func (s *scraper) ScrapeMetrics(ctx context.Context) (pdata.MetricSlice, error) {
+	_, span := trace.StartSpan(ctx, "loadscraper.ScrapeMetrics")
+	defer span.End()
+
+	metrics := pdata.NewMetricSlice()
+
+	avgLoadValues, err := getSampledLoadAverages()
+	if err != nil {
+		return metrics, err
+	}
+
+	metrics.Resize(3)
+	initializeLoadMetric(metrics.At(0), metric1MLoadDescriptor, avgLoadValues.Load1)
+	initializeLoadMetric(metrics.At(1), metric5MLoadDescriptor, avgLoadValues.Load5)
+	initializeLoadMetric(metrics.At(2), metric15MLoadDescriptor, avgLoadValues.Load15)
+	return metrics, nil
+}
+
+func initializeLoadMetric(metric pdata.Metric, metricDescriptor pdata.MetricDescriptor, value float64) {
+	metricDescriptor.CopyTo(metric.MetricDescriptor())
+
+	idps := metric.DoubleDataPoints()
+	idps.Resize(1)
+	dp := idps.At(0)
+	dp.SetTimestamp(pdata.TimestampUnixNano(uint64(time.Now().UnixNano())))
+	dp.SetValue(value)
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/load_scraper_others.go

@@ -0,0 +1,37 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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.
+
+// +build !windows
+
+package loadscraper
+
+import (
+	"context"
+
+	"github.com/shirou/gopsutil/load"
+	"go.uber.org/zap"
+)
+
+// unix based systems sample & compute load averages in the kernel, so nothing to do here
+func startSampling(_ context.Context, _ *zap.Logger) error {
+	return nil
+}
+
+func stopSampling(_ context.Context) error {
+	return nil
+}
+
+func getSampledLoadAverages() (*load.AvgStat, error) {
+	return load.Avg()
+}

receiver/hostmetricsreceiver/internal/scraper/loadscraper/load_scraper_test.go

@@ -0,0 +1,58 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// 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 loadscraper
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+
+	"go.opentelemetry.io/collector/consumer/pdata"
+	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal"
+)
+
+type validationFn func(*testing.T, pdata.MetricSlice)
+
+func TestScrapeMetrics(t *testing.T) {
+	createScraperAndValidateScrapedMetrics(t, &Config{}, func(t *testing.T, metrics pdata.MetricSlice) {
+		// expect 3 metrics
+		assert.Equal(t, 3, metrics.Len())
+
+		// expect a single datapoint for 1m, 5m & 15m load metrics
+		assertMetricHasSingleDatapoint(t, metrics.At(0), metric1MLoadDescriptor)
+		assertMetricHasSingleDatapoint(t, metrics.At(1), metric5MLoadDescriptor)
+		assertMetricHasSingleDatapoint(t, metrics.At(2), metric15MLoadDescriptor)
+	})
+}
+
+func assertMetricHasSingleDatapoint(t *testing.T, metric pdata.Metric, descriptor pdata.MetricDescriptor) {
+	internal.AssertDescriptorEqual(t, descriptor, metric.MetricDescriptor())
+	assert.Equal(t, 1, metric.DoubleDataPoints().Len())
+}
+
+func createScraperAndValidateScrapedMetrics(t *testing.T, config *Config, assertFn validationFn) {
+	scraper := newLoadScraper(context.Background(), zap.NewNop(), config)
+	err := scraper.Initialize(context.Background())
+	require.NoError(t, err, "Failed to initialize load scraper: %v", err)
+	defer func() { assert.NoError(t, scraper.Close(context.Background())) }()
+
+	metrics, err := scraper.ScrapeMetrics(context.Background())
+	require.NoError(t, err, "Failed to scrape metrics: %v", err)
+
+	assertFn(t, metrics)
+}