Rename [Trace|Metrics]DataProcessor to [Trace|Metrics]Consumer, add TraceProcessor similar to receiver,exporter. (#473)

* Rename [Trace|Metrics]DataProcessor to [Trace|Metrics]Processor

* Rename TraceProcessor to TraceConsumer as discussed.

* Add empty_test for processor.

Author: Bogdan Drutu

cmd/ocagent/main.go

@@ -33,12 +33,13 @@ import (
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 
+	"github.com/census-instrumentation/opencensus-service/consumer"
 	"github.com/census-instrumentation/opencensus-service/internal/config"
 	"github.com/census-instrumentation/opencensus-service/internal/config/viperutils"
 	"github.com/census-instrumentation/opencensus-service/internal/pprofserver"
 	"github.com/census-instrumentation/opencensus-service/internal/version"
 	"github.com/census-instrumentation/opencensus-service/observability"
-	"github.com/census-instrumentation/opencensus-service/processor"
+	"github.com/census-instrumentation/opencensus-service/processor/multiconsumer"
 	"github.com/census-instrumentation/opencensus-service/receiver/jaegerreceiver"
 	"github.com/census-instrumentation/opencensus-service/receiver/opencensusreceiver"
 	"github.com/census-instrumentation/opencensus-service/receiver/prometheusreceiver"
@@ -117,8 +118,8 @@ func runOCAgent() {
 		log.Fatalf("Config: failed to create exporters from YAML: %v", err)
 	}
 
-	commonSpanSink := processor.NewMultiTraceDataProcessor(traceExporters)
-	commonMetricsSink := processor.NewMultiMetricsDataProcessor(metricsExporters)
+	commonSpanSink := multiconsumer.NewTraceProcessor(traceExporters)
+	commonMetricsSink := multiconsumer.NewMetricsProcessor(metricsExporters)
 
 	// Add other receivers here as they are implemented
 	ocReceiverDoneFn, err := runOCReceiver(logger, &agentConfig, commonSpanSink, commonMetricsSink)
@@ -213,7 +214,7 @@ func runZPages(port int) func() error {
 	return srv.Close
 }
 
-func runOCReceiver(logger *zap.Logger, acfg *config.Config, tdp processor.TraceDataProcessor, mdp processor.MetricsDataProcessor) (doneFn func() error, err error) {
+func runOCReceiver(logger *zap.Logger, acfg *config.Config, tdp consumer.TraceConsumer, mdp consumer.MetricsConsumer) (doneFn func() error, err error) {
 	tlsCredsOption, hasTLSCreds, err := acfg.OpenCensusReceiverTLSCredentialsServerOption()
 	if err != nil {
 		return nil, fmt.Errorf("OpenCensus receiver TLS Credentials: %v", err)
@@ -270,7 +271,7 @@ func runOCReceiver(logger *zap.Logger, acfg *config.Config, tdp processor.TraceD
 	return doneFn, nil
 }
 
-func runJaegerReceiver(collectorThriftPort, collectorHTTPPort int, next processor.TraceDataProcessor) (doneFn func() error, err error) {
+func runJaegerReceiver(collectorThriftPort, collectorHTTPPort int, next consumer.TraceConsumer) (doneFn func() error, err error) {
 	jtr, err := jaegerreceiver.New(context.Background(), &jaegerreceiver.Configuration{
 		CollectorThriftPort: collectorThriftPort,
 		CollectorHTTPPort:   collectorHTTPPort,
@@ -292,7 +293,7 @@ func runJaegerReceiver(collectorThriftPort, collectorHTTPPort int, next processo
 	return doneFn, nil
 }
 
-func runZipkinReceiver(addr string, next processor.TraceDataProcessor) (doneFn func() error, err error) {
+func runZipkinReceiver(addr string, next consumer.TraceConsumer) (doneFn func() error, err error) {
 	zi, err := zipkinreceiver.New(addr)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create the Zipkin receiver: %v", err)
@@ -308,7 +309,7 @@ func runZipkinReceiver(addr string, next processor.TraceDataProcessor) (doneFn f
 	return doneFn, nil
 }
 
-func runZipkinScribeReceiver(config *config.ScribeReceiverConfig, next processor.TraceDataProcessor) (doneFn func() error, err error) {
+func runZipkinScribeReceiver(config *config.ScribeReceiverConfig, next consumer.TraceConsumer) (doneFn func() error, err error) {
 	zs, err := scribe.NewReceiver(config.Address, config.Port, config.Category)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create the Zipkin Scribe receiver: %v", err)
@@ -324,7 +325,7 @@ func runZipkinScribeReceiver(config *config.ScribeReceiverConfig, next processor
 	return doneFn, nil
 }
 
-func runPrometheusReceiver(v *viper.Viper, next processor.MetricsDataProcessor) (doneFn func() error, err error) {
+func runPrometheusReceiver(v *viper.Viper, next consumer.MetricsConsumer) (doneFn func() error, err error) {
 	pmr, err := prometheusreceiver.New(v.Sub("receivers.prometheus"))
 	if err != nil {
 		return nil, err

cmd/occollector/app/collector/processors.go

@@ -26,17 +26,17 @@ import (
 
 	"github.com/census-instrumentation/opencensus-service/cmd/occollector/app/builder"
 	"github.com/census-instrumentation/opencensus-service/cmd/occollector/app/sender"
+	"github.com/census-instrumentation/opencensus-service/consumer"
 	"github.com/census-instrumentation/opencensus-service/exporter/loggingexporter"
 	"github.com/census-instrumentation/opencensus-service/internal/collector/processor"
 	"github.com/census-instrumentation/opencensus-service/internal/collector/processor/nodebatcher"
 	"github.com/census-instrumentation/opencensus-service/internal/collector/processor/queued"
 	"github.com/census-instrumentation/opencensus-service/internal/collector/processor/tailsampling"
 	"github.com/census-instrumentation/opencensus-service/internal/collector/sampling"
 	"github.com/census-instrumentation/opencensus-service/internal/config"
-	mainprocessor "github.com/census-instrumentation/opencensus-service/processor"
 )
 
-func createExporters(v *viper.Viper, logger *zap.Logger) ([]func(), []mainprocessor.TraceDataProcessor, []mainprocessor.MetricsDataProcessor) {
+func createExporters(v *viper.Viper, logger *zap.Logger) ([]func(), []consumer.TraceConsumer, []consumer.MetricsConsumer) {
 	// TODO: (@pjanotti) this is slightly modified from agent but in the end duplication, need to consolidate style and visibility.
 	traceExporters, metricsExporters, doneFns, err := config.ExportersFromViperConfig(logger, v)
 	if err != nil {

consumer/consumer.go

@@ -0,0 +1,37 @@
+// Copyright 2019, OpenCensus 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 consumer
+
+import (
+	"context"
+
+	"github.com/census-instrumentation/opencensus-service/data"
+)
+
+// MetricsConsumer is an interface that receives data.MetricsData, process it as needed, and
+// sends it to the next processing node if any or to the destination.
+//
+// ConsumeMetricsData receives data.MetricsData for processing by the MetricsConsumer.
+type MetricsConsumer interface {
+	ConsumeMetricsData(ctx context.Context, md data.MetricsData) error
+}
+
+// TraceConsumer is an interface that receives data.TraceData, process it as needed, and
+// sends it to the next processing node if any or to the destination.
+//
+// ConsumeTraceData receives data.TraceData for processing by the TraceConsumer.
+type TraceConsumer interface {
+	ConsumeTraceData(ctx context.Context, td data.TraceData) error
+}

consumer/empty_test.go

@@ -0,0 +1,17 @@
+// Copyright 2019, OpenCensus 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 consumer
+
+// Package with interface only.

exporter/awsexporter/aws_xray.go

@@ -26,9 +26,9 @@ import (
 
 	"github.com/spf13/viper"
 
+	"github.com/census-instrumentation/opencensus-service/consumer"
 	"github.com/census-instrumentation/opencensus-service/data"
 	"github.com/census-instrumentation/opencensus-service/exporter/exporterwrapper"
-	"github.com/census-instrumentation/opencensus-service/processor"
 )
 
 const defaultVersionForAWSXRayApplications = "latest"
@@ -57,11 +57,11 @@ type awsXRayExporter struct {
 	defaultOptions     []xray.Option
 }
 
-var _ processor.TraceDataProcessor = (*awsXRayExporter)(nil)
+var _ consumer.TraceConsumer = (*awsXRayExporter)(nil)
 
-// AWSXRayTraceExportersFromViper unmarshals the viper and returns an processor.TraceDataProcessor targeting
+// AWSXRayTraceExportersFromViper unmarshals the viper and returns an consumer.TraceConsumer targeting
 // AWS X-Ray according to the configuration settings.
-func AWSXRayTraceExportersFromViper(v *viper.Viper) (tdps []processor.TraceDataProcessor, mdps []processor.MetricsDataProcessor, doneFns []func() error, err error) {
+func AWSXRayTraceExportersFromViper(v *viper.Viper) (tps []consumer.TraceConsumer, mps []consumer.MetricsConsumer, doneFns []func() error, err error) {
 	var cfg struct {
 		AWSXRay *awsXRayConfig `mapstructure:"aws-xray"`
 	}
@@ -84,7 +84,7 @@ func AWSXRayTraceExportersFromViper(v *viper.Viper) (tdps []processor.TraceDataP
 		defaultServiceName:     xc.DefaultServiceName,
 	}
 
-	tdps = append(tdps, axe)
+	tps = append(tps, axe)
 	doneFns = append(doneFns, func() error {
 		axe.Flush()
 		return nil
@@ -146,7 +146,7 @@ func transformConfigToXRayOptions(axrCfg *awsXRayConfig) (xopts []xray.Option, e
 
 // ExportSpans is the method that translates OpenCensus-Proto Traces into AWS X-Ray spans.
 // It uniquely maintains
-func (axe *awsXRayExporter) ProcessTraceData(ctx context.Context, td data.TraceData) (xerr error) {
+func (axe *awsXRayExporter) ConsumeTraceData(ctx context.Context, td data.TraceData) (xerr error) {
 	ctx, span := trace.StartSpan(ctx,
 		"opencensus.service.exporter.aws_xray.ExportSpans",
 		trace.WithSampler(trace.NeverSample()))

exporter/datadogexporter/datadog.go

@@ -18,8 +18,8 @@ import (
 	datadog "github.com/DataDog/opencensus-go-exporter-datadog"
 	"github.com/spf13/viper"
 
+	"github.com/census-instrumentation/opencensus-service/consumer"
 	"github.com/census-instrumentation/opencensus-service/exporter/exporterwrapper"
-	"github.com/census-instrumentation/opencensus-service/processor"
 )
 
 type datadogConfig struct {
@@ -43,7 +43,7 @@ type datadogConfig struct {
 
 // DatadogTraceExportersFromViper unmarshals the viper and returns an exporter.TraceExporter targeting
 // Datadog according to the configuration settings.
-func DatadogTraceExportersFromViper(v *viper.Viper) (tdps []processor.TraceDataProcessor, mdps []processor.MetricsDataProcessor, doneFns []func() error, err error) {
+func DatadogTraceExportersFromViper(v *viper.Viper) (tps []consumer.TraceConsumer, mps []consumer.MetricsConsumer, doneFns []func() error, err error) {
 	var cfg struct {
 		Datadog *datadogConfig `mapstructure:"datadog,omitempty"`
 	}
@@ -74,7 +74,7 @@ func DatadogTraceExportersFromViper(v *viper.Viper) (tdps []processor.TraceDataP
 	// TODO: Examine the Datadog exporter to see
 	// if trace.ExportSpan was constraining and if perhaps the
 	// upload can use the context and information from the Node.
-	tdps = append(tdps, exporterwrapper.NewExporterWrapper("datadog", de))
+	tps = append(tps, exporterwrapper.NewExporterWrapper("datadog", de))
 
 	// TODO: (@odeke-em, @songya23) implement ExportMetrics for Datadog.
 	// mes = append(mes, oexp)

exporter/exporter.go

@@ -0,0 +1,39 @@
+// Copyright 2019, OpenCensus 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 exporter
+
+import (
+	"github.com/census-instrumentation/opencensus-service/consumer"
+)
+
+// TraceExporter composes TraceConsumer with some additional exporter-specific functions.
+type TraceExporter interface {
+	consumer.TraceConsumer
+
+	// TraceExportFormat gets the name of the format in which this exporter sends its data.
+	// For exporters that can export multiple signals it is recommended to encode the signal
+	// as suffix (e.g. "oc_trace").
+	TraceExportFormat() string
+}
+
+// MetricsExporter composes MetricsConsumer with some additional exporter-specific functions.
+type MetricsExporter interface {
+	consumer.MetricsConsumer
+
+	// MetricsExportFormat gets the name of the format in which this exporter sends its data.
+	// For exporters that can export multiple signals it is recommended to encode the signal
+	// as suffix (e.g. "oc_metrics").
+	MetricsExportFormat() string
+}

exporter/exportertest/nop_exporter.go

@@ -26,11 +26,11 @@ type nopExporter int
 var _ exporter.TraceExporter = (*nopExporter)(nil)
 var _ exporter.MetricsExporter = (*nopExporter)(nil)
 
-func (ne *nopExporter) ProcessTraceData(ctx context.Context, td data.TraceData) error {
+func (ne *nopExporter) ConsumeTraceData(ctx context.Context, td data.TraceData) error {
 	return nil
 }
 
-func (ne *nopExporter) ProcessMetricsData(ctx context.Context, md data.MetricsData) error {
+func (ne *nopExporter) ConsumeMetricsData(ctx context.Context, md data.MetricsData) error {
 	return nil
 }
 

exporter/exportertest/nop_exporter_test.go

@@ -27,7 +27,7 @@ func TestNopTraceExporterNoErrors(t *testing.T) {
 	td := data.TraceData{
 		Spans: make([]*tracepb.Span, 7),
 	}
-	if err := nte.ProcessTraceData(context.Background(), td); err != nil {
+	if err := nte.ConsumeTraceData(context.Background(), td); err != nil {
 		t.Errorf("Wanted nil got error")
 		return
 	}
@@ -42,7 +42,7 @@ func TestNoopMetricsExporterNoErrors(t *testing.T) {
 	md := data.MetricsData{
 		Metrics: make([]*metricspb.Metric, 7),
 	}
-	if err := nme.ProcessMetricsData(context.Background(), md); err != nil {
+	if err := nme.ConsumeMetricsData(context.Background(), md); err != nil {
 		t.Errorf("Wanted nil got error")
 		return
 	}

exporter/exportertest/sink_exporter.go

@@ -30,8 +30,8 @@ type SinkTraceExporter struct {
 
 var _ exporter.TraceExporter = (*SinkTraceExporter)(nil)
 
-// ProcessTraceData stores traces for tests.
-func (ste *SinkTraceExporter) ProcessTraceData(ctx context.Context, td data.TraceData) error {
+// ConsumeTraceData stores traces for tests.
+func (ste *SinkTraceExporter) ConsumeTraceData(ctx context.Context, td data.TraceData) error {
 	ste.mu.Lock()
 	defer ste.mu.Unlock()
 
@@ -66,8 +66,8 @@ type SinkMetricsExporter struct {
 
 var _ exporter.MetricsExporter = (*SinkMetricsExporter)(nil)
 
-// ProcessMetricsData stores traces for tests.
-func (sme *SinkMetricsExporter) ProcessMetricsData(ctx context.Context, md data.MetricsData) error {
+// ConsumeMetricsData stores traces for tests.
+func (sme *SinkMetricsExporter) ConsumeMetricsData(ctx context.Context, md data.MetricsData) error {
 	sme.mu.Lock()
 	defer sme.mu.Unlock()