Migrate Prometheus to the new MetricsExporter interface (#1477)

Signed-off-by: Bogdan Drutu <bogdandrutu@gmail.com>

exporter/prometheusexporter/config_test.go

@@ -30,7 +30,7 @@ func TestLoadConfig(t *testing.T) {
 	factories, err := componenttest.ExampleComponents()
 	assert.NoError(t, err)
 
-	factory := &Factory{}
+	factory := NewFactory()
 	factories.Exporters[typeStr] = factory
 	cfg, err := configtest.LoadConfigFile(t, path.Join(".", "testdata", "config.yaml"), factories)
 

exporter/prometheusexporter/factory.go

@@ -15,34 +15,32 @@
 package prometheusexporter
 
 import (
+	"context"
 	"net"
 	"net/http"
 	"strings"
 
 	"github.com/orijtech/prometheus-go-metrics-exporter"
-	"go.uber.org/zap"
 
 	"go.opentelemetry.io/collector/component"
-	"go.opentelemetry.io/collector/config/configerror"
 	"go.opentelemetry.io/collector/config/configmodels"
+	"go.opentelemetry.io/collector/exporter/exporterhelper"
 )
 
 const (
 	// The value of "type" key in configuration.
 	typeStr = "prometheus"
 )
 
-// Factory is the factory for Prometheus exporter.
-type Factory struct {
+// NewFactory creates a factory for OTLP exporter.
+func NewFactory() component.ExporterFactory {
+	return exporterhelper.NewFactory(
+		typeStr,
+		createDefaultConfig,
+		exporterhelper.WithMetrics(createMetricsExporter))
 }
 
-// Type gets the type of the Exporter config created by this factory.
-func (f *Factory) Type() configmodels.Type {
-	return typeStr
-}
-
-// CreateDefaultConfig creates the default configuration for exporter.
-func (f *Factory) CreateDefaultConfig() configmodels.Exporter {
+func createDefaultConfig() configmodels.Exporter {
 	return &Config{
 		ExporterSettings: configmodels.ExporterSettings{
 			TypeVal: typeStr,
@@ -52,13 +50,11 @@ func (f *Factory) CreateDefaultConfig() configmodels.Exporter {
 	}
 }
 
-// CreateTraceExporter creates a trace exporter based on this config.
-func (f *Factory) CreateTraceExporter(logger *zap.Logger, config configmodels.Exporter) (component.TraceExporterOld, error) {
-	return nil, configerror.ErrDataTypeIsNotSupported
-}
-
-// CreateMetricsExporter creates a metrics exporter based on this config.
-func (f *Factory) CreateMetricsExporter(logger *zap.Logger, cfg configmodels.Exporter) (component.MetricsExporterOld, error) {
+func createMetricsExporter(
+	_ context.Context,
+	_ component.ExporterCreateParams,
+	cfg configmodels.Exporter,
+) (component.MetricsExporter, error) {
 	pcfg := cfg.(*Config)
 
 	addr := strings.TrimSpace(pcfg.Endpoint)

exporter/prometheusexporter/factory_test.go

@@ -15,39 +15,31 @@
 package prometheusexporter
 
 import (
+	"context"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap"
 
+	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/config/configcheck"
-	"go.opentelemetry.io/collector/config/configerror"
 )
 
 func TestCreateDefaultConfig(t *testing.T) {
-	factory := Factory{}
-	require.NotNil(t, factory)
-
-	cfg := factory.CreateDefaultConfig()
+	cfg := createDefaultConfig()
 	assert.NotNil(t, cfg, "failed to create default config")
 	assert.NoError(t, configcheck.ValidateConfig(cfg))
 }
 
-func TestCreateTraceExporter(t *testing.T) {
-	factory := Factory{}
-	cfg := factory.CreateDefaultConfig()
-
-	_, err := factory.CreateTraceExporter(zap.NewNop(), cfg)
-	assert.Error(t, err, configerror.ErrDataTypeIsNotSupported)
-}
-
 func TestCreateMetricsExporter(t *testing.T) {
-	factory := Factory{}
-	cfg := factory.CreateDefaultConfig()
+	cfg := createDefaultConfig()
 	oCfg := cfg.(*Config)
 	oCfg.Endpoint = ""
-	consumer, err := factory.CreateMetricsExporter(zap.NewNop(), oCfg)
+	exp, err := createMetricsExporter(
+		context.Background(),
+		component.ExporterCreateParams{Logger: zap.NewNop()},
+		cfg)
 	require.Equal(t, errBlankPrometheusAddress, err)
-	require.Nil(t, consumer)
+	require.Nil(t, exp)
 }

exporter/prometheusexporter/prometheus.go

@@ -25,8 +25,8 @@ import (
 	"github.com/orijtech/prometheus-go-metrics-exporter"
 
 	"go.opentelemetry.io/collector/component"
-	"go.opentelemetry.io/collector/consumer"
-	"go.opentelemetry.io/collector/consumer/consumerdata"
+	"go.opentelemetry.io/collector/consumer/pdata"
+	"go.opentelemetry.io/collector/consumer/pdatautil"
 )
 
 var errBlankPrometheusAddress = errors.New("expecting a non-blank address to run the Prometheus metrics handler")
@@ -37,19 +37,20 @@ type prometheusExporter struct {
 	shutdownFunc func() error
 }
 
-var _ consumer.MetricsConsumerOld = (*prometheusExporter)(nil)
-
 func (pe *prometheusExporter) Start(_ context.Context, _ component.Host) error {
 	return nil
 }
 
-func (pe *prometheusExporter) ConsumeMetricsData(ctx context.Context, md consumerdata.MetricsData) error {
-	merged := make(map[string]*metricspb.Metric)
-	for _, metric := range md.Metrics {
-		merge(merged, metric)
-	}
-	for _, metric := range merged {
-		_ = pe.exporter.ExportMetric(ctx, md.Node, md.Resource, metric)
+func (pe *prometheusExporter) ConsumeMetrics(ctx context.Context, md pdata.Metrics) error {
+	ocmds := pdatautil.MetricsToMetricsData(md)
+	for _, ocmd := range ocmds {
+		merged := make(map[string]*metricspb.Metric)
+		for _, metric := range ocmd.Metrics {
+			merge(merged, metric)
+		}
+		for _, metric := range merged {
+			_ = pe.exporter.ExportMetric(ctx, ocmd.Node, ocmd.Resource, metric)
+		}
 	}
 	return nil
 }

exporter/prometheusexporter/prometheus_test.go

@@ -28,7 +28,9 @@ import (
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap"
 
+	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/consumer/consumerdata"
+	"go.opentelemetry.io/collector/consumer/pdatautil"
 )
 
 func TestPrometheusExporter(t *testing.T) {
@@ -52,21 +54,24 @@ func TestPrometheusExporter(t *testing.T) {
 		},
 	}
 
-	factory := Factory{}
+	factory := NewFactory()
+	creationParams := component.ExporterCreateParams{Logger: zap.NewNop()}
 	for _, tt := range tests {
 		// Run it a few times to ensure that shutdowns exit cleanly.
 		for j := 0; j < 3; j++ {
-			consumer, err := factory.CreateMetricsExporter(zap.NewNop(), tt.config)
+			exp, err := factory.CreateMetricsExporter(context.Background(), creationParams, tt.config)
 
 			if tt.wantErr != "" {
-				require.Equal(t, tt.wantErr, err.Error())
+				require.Error(t, err)
+				assert.Equal(t, tt.wantErr, err.Error())
 				continue
+			} else {
+				require.NoError(t, err)
 			}
 
-			assert.NotNil(t, consumer)
-
+			assert.NotNil(t, exp)
 			require.Nil(t, err)
-			require.NoError(t, consumer.Shutdown(context.Background()))
+			require.NoError(t, exp.Shutdown(context.Background()))
 		}
 	}
 }
@@ -81,16 +86,20 @@ func TestPrometheusExporter_endToEnd(t *testing.T) {
 		Endpoint: ":7777",
 	}
 
-	factory := Factory{}
-	consumer, err := factory.CreateMetricsExporter(zap.NewNop(), config)
+	factory := NewFactory()
+	creationParams := component.ExporterCreateParams{Logger: zap.NewNop()}
+	exp, err := factory.CreateMetricsExporter(context.Background(), creationParams, config)
 	assert.NoError(t, err)
 
-	defer consumer.Shutdown(context.Background())
+	t.Cleanup(func() {
+		require.NoError(t, exp.Shutdown(context.Background()))
+	})
 
-	assert.NotNil(t, consumer)
+	assert.NotNil(t, exp)
 
 	for delta := 0; delta <= 20; delta += 10 {
-		consumer.ConsumeMetricsData(context.Background(), consumerdata.MetricsData{Metrics: metricBuilder(int64(delta))})
+		md := pdatautil.MetricsFromMetricsData([]consumerdata.MetricsData{{Metrics: metricBuilder(int64(delta))}})
+		assert.NoError(t, exp.ConsumeMetrics(context.Background(), md))
 
 		res, err := http.Get("http://localhost:7777/metrics")
 		require.NoError(t, err, "Failed to perform a scrape")

service/defaultcomponents/defaults.go

@@ -81,7 +81,7 @@ func Components() (
 
 	exporters, err := component.MakeExporterFactoryMap(
 		&opencensusexporter.Factory{},
-		&prometheusexporter.Factory{},
+		prometheusexporter.NewFactory(),
 		loggingexporter.NewFactory(),
 		zipkinexporter.NewFactory(),
 		jaegerexporter.NewFactory(),