feat: implement gRPC storage plugin for metrics

Makefile

@@ -520,7 +520,7 @@ proto: init-submodules proto-prepare-otel
 	$(PROTOC) \
 		$(PROTO_INCLUDES) \
 		-Iplugin/storage/grpc/proto \
-		--gogo_out=plugins=grpc,$(PROTO_GOGO_MAPPINGS):$(PWD)/proto-gen/storage_v1 \
+		--gogo_out=plugins=grpc,$(PROTO_GOGO_MAPPINGS),Mopenmetrics.proto=github.com/jaegertracing/jaeger/proto-gen/api_v2/metrics:$(PWD)/proto-gen/storage_v1 \
 		plugin/storage/grpc/proto/storage.proto
 
 	$(PROTOC) \

cmd/query/main.go

@@ -55,8 +55,7 @@ func main() {
 		log.Fatalf("Cannot initialize storage factory: %v", err)
 	}
 
-	fc := metricsPlugin.FactoryConfigFromEnv()
-	metricsReaderFactory, err := metricsPlugin.NewFactory(fc)
+	metricsReaderFactory, err := metricsPlugin.NewFactory(metricsPlugin.FactoryConfigFromEnv())
 	if err != nil {
 		log.Fatalf("Cannot initialize metrics factory: %v", err)
 	}
@@ -179,12 +178,13 @@ func createMetricsQueryService(
 	logger *zap.Logger,
 	metricsReaderMetricsFactory metrics.Factory,
 ) (querysvc.MetricsQueryService, error) {
+	// Ensure default parameter values are loaded correctly.
+	metricsReaderFactory.InitFromViper(v, logger)
+
 	if err := metricsReaderFactory.Initialize(logger); err != nil {
 		return nil, fmt.Errorf("failed to init metrics reader factory: %w", err)
 	}
 
-	// Ensure default parameter values are loaded correctly.
-	metricsReaderFactory.InitFromViper(v, logger)
 	reader, err := metricsReaderFactory.CreateMetricsReader()
 	if err != nil {
 		return nil, fmt.Errorf("failed to create metrics reader: %w", err)

plugin/metrics/factory.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/jaegertracing/jaeger/plugin"
 	"github.com/jaegertracing/jaeger/plugin/metrics/disabled"
+	"github.com/jaegertracing/jaeger/plugin/metrics/grpc"
 	"github.com/jaegertracing/jaeger/plugin/metrics/prometheus"
 	"github.com/jaegertracing/jaeger/storage"
 	"github.com/jaegertracing/jaeger/storage/metricsstore"
@@ -33,6 +34,7 @@ const (
 	disabledStorageType = ""
 
 	prometheusStorageType = "prometheus"
+	grpcStorageType       = "grpc-plugin"
 )
 
 // AllStorageTypes defines all available storage backends.
@@ -67,6 +69,8 @@ func (f *Factory) getFactoryOfType(factoryType string) (storage.MetricsFactory,
 	switch factoryType {
 	case prometheusStorageType:
 		return prometheus.NewFactory(), nil
+	case grpcStorageType:
+		return grpc.NewFactory(), nil
 	case disabledStorageType:
 		return disabled.NewFactory(), nil
 	}
@@ -76,7 +80,9 @@ func (f *Factory) getFactoryOfType(factoryType string) (storage.MetricsFactory,
 // Initialize implements storage.MetricsFactory.
 func (f *Factory) Initialize(logger *zap.Logger) error {
 	for _, factory := range f.factories {
-		factory.Initialize(logger)
+		if err := factory.Initialize(logger); err != nil {
+			return err
+		}
 	}
 	return nil
 }

plugin/metrics/grpc/factory.go

@@ -0,0 +1,99 @@
+// Copyright (c) 2023 The Jaeger 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 grpc
+
+import (
+	"flag"
+	"fmt"
+	"io"
+
+	"github.com/spf13/viper"
+	"go.uber.org/zap"
+
+	"github.com/jaegertracing/jaeger/plugin"
+	"github.com/jaegertracing/jaeger/plugin/storage/grpc/config"
+	"github.com/jaegertracing/jaeger/plugin/storage/grpc/shared"
+	"github.com/jaegertracing/jaeger/storage"
+	"github.com/jaegertracing/jaeger/storage/metricsstore"
+)
+
+var (
+	_ plugin.Configurable = (*Factory)(nil)
+	_ io.Closer           = (*Factory)(nil)
+)
+
+// Factory implements storage.MetricsFactory
+type Factory struct {
+	options Options
+	logger  *zap.Logger
+
+	builder config.PluginBuilder
+
+	metricsReader shared.MetricsReaderPlugin
+	capabilities  shared.PluginCapabilities
+}
+
+// NewFactory creates a new Factory
+func NewFactory() *Factory {
+	return &Factory{}
+}
+
+// AddFlags implements plugin.Configurable
+func (f *Factory) AddFlags(flagSet *flag.FlagSet) {
+	f.options.AddFlags(flagSet)
+}
+
+// InitFromViper implements plugin.Configurable
+func (f *Factory) InitFromViper(v *viper.Viper, logger *zap.Logger) {
+	if err := f.options.InitFromViper(v); err != nil {
+		logger.Fatal("unable to initialize gRPC metrics factory", zap.Error(err))
+	}
+	f.builder = &f.options.Configuration
+}
+
+// Initialize implements storage.MetricsFactory
+func (f *Factory) Initialize(logger *zap.Logger) error {
+	f.logger = logger
+
+	services, err := f.builder.Build(logger)
+	if err != nil {
+		return fmt.Errorf("grpc-plugin builder failed to create a store: %w", err)
+	}
+
+	f.metricsReader = services.MetricsReader
+	f.capabilities = services.Capabilities
+	logger.Info("External plugin storage configuration", zap.Any("configuration", f.options.Configuration))
+	return nil
+}
+
+// CreateMetricsReader implements storage.MetricsFactory
+func (f *Factory) CreateMetricsReader() (metricsstore.Reader, error) {
+	if f.capabilities == nil {
+		return nil, storage.ErrMetricsStorageNotSupported
+	}
+	capabilities, err := f.capabilities.Capabilities()
+	if err != nil {
+		return nil, err
+	}
+	if capabilities == nil || !capabilities.MetricsReader {
+		return nil, storage.ErrMetricsStorageNotSupported
+	}
+	return f.metricsReader.MetricsReader(), nil
+}
+
+// Close closes the resources held by the factory
+func (f *Factory) Close() error {
+	return f.builder.Close()
+}

plugin/metrics/grpc/factory_test.go

@@ -0,0 +1,17 @@
+// Copyright (c) 2023 The Jaeger 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 grpc
+
+// TODO write tests

plugin/metrics/grpc/options.go

@@ -0,0 +1,69 @@
+// Copyright (c) 2023 The Jaeger 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 grpc
+
+import (
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/spf13/viper"
+
+	"github.com/jaegertracing/jaeger/pkg/config/tlscfg"
+	"github.com/jaegertracing/jaeger/pkg/tenancy"
+	"github.com/jaegertracing/jaeger/plugin/storage/grpc/config"
+)
+
+const (
+	remotePrefix             = "grpc-metrics"
+	remoteServer             = remotePrefix + ".server"
+	remoteConnectionTimeout  = remotePrefix + ".connection-timeout"
+	defaultConnectionTimeout = time.Duration(5 * time.Second)
+)
+
+type Options struct {
+	Configuration config.Configuration `mapstructure:",squash"`
+}
+
+func NewOptions() *Options {
+	return &Options{}
+}
+
+func tlsFlagsConfig() tlscfg.ClientFlagsConfig {
+	return tlscfg.ClientFlagsConfig{
+		Prefix: remotePrefix,
+	}
+}
+
+// AddFlags adds flags for Options
+func (opt *Options) AddFlags(flagSet *flag.FlagSet) {
+	tlsFlagsConfig().AddFlags(flagSet)
+
+	flagSet.String(remoteServer, "", "The remote metrics gRPC server address as host:port")
+	flagSet.Duration(remoteConnectionTimeout, defaultConnectionTimeout, "The remote metrics gRPC server connection timeout")
+}
+
+// InitFromViper initializes Options with properties from viper
+func (opt *Options) InitFromViper(v *viper.Viper) error {
+	opt.Configuration.RemoteServerAddr = v.GetString(remoteServer)
+	var err error
+	opt.Configuration.RemoteTLS, err = tlsFlagsConfig().InitFromViper(v)
+	if err != nil {
+		return fmt.Errorf("failed to parse gRPC storage TLS options: %w", err)
+	}
+	opt.Configuration.RemoteConnectTimeout = v.GetDuration(remoteConnectionTimeout)
+	opt.Configuration.TenancyOpts = tenancy.InitFromViper(v)
+	return nil
+}

plugin/metrics/grpc/options_test.go

@@ -0,0 +1,17 @@
+// Copyright (c) 2023 The Jaeger 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 grpc
+
+// TODO write tests

plugin/storage/grpc/config/config.go

@@ -118,6 +118,7 @@ func (c *Configuration) buildRemote(logger *zap.Logger) (*ClientPluginServices,
 			Store:               grpcClient,
 			ArchiveStore:        grpcClient,
 			StreamingSpanWriter: grpcClient,
+			MetricsReader:       grpcClient,
 		},
 		Capabilities: grpcClient,
 	}, nil

plugin/storage/grpc/grpc.go

@@ -38,6 +38,7 @@ func ServeWithGRPCServer(services *shared.PluginServices, grpcServer func([]grpc
 					Impl:        services.Store,
 					ArchiveImpl: services.ArchiveStore,
 					StreamImpl:  services.StreamingSpanWriter,
+					MetricsImpl: services.MetricsReader,
 				},
 			},
 		},

plugin/storage/grpc/proto/storage.proto

@@ -23,6 +23,7 @@ import "google/protobuf/timestamp.proto";
 import "google/protobuf/duration.proto";
 
 import "model.proto";
+import "openmetrics.proto";
 
 // Enable gogoprotobuf extensions (https://github.com/gogo/protobuf/blob/master/extensions.md).
 // Enable custom Marshal method.
@@ -174,6 +175,56 @@ service DependenciesReaderPlugin {
     rpc GetDependencies(GetDependenciesRequest) returns (GetDependenciesResponse);
 }
 
+service MetricsReaderPlugin {
+    // metricsstore/Reader
+    rpc GetLatencies(GetLatenciesRequest) returns (GetLatenciesResponse);
+    rpc GetCallRates(GetCallRatesRequest) returns (GetCallRatesResponse);
+    rpc GetErrorRates(GetErrorRatesRequest) returns (GetErrorRatesResponse);
+    rpc GetMinStepDuration(GetMinStepDurationRequest) returns (GetMinStepDurationResponse);
+}
+
+message MetricsBaseQueryParameters {
+    repeated string service_names = 1;
+    bool group_by_operation = 2;
+    google.protobuf.Timestamp end_time = 3;
+    google.protobuf.Duration lookback = 4;
+    google.protobuf.Duration step = 5;
+    google.protobuf.Duration rate_per = 6;
+    repeated string span_kinds = 7;
+}
+
+message GetLatenciesRequest {
+    MetricsBaseQueryParameters base_query_parameters = 1;
+    float quantile = 2;
+}
+
+message GetLatenciesResponse {
+    jaeger.api_v2.metrics.MetricFamily metric_family = 1;
+}
+
+message GetCallRatesRequest {
+    MetricsBaseQueryParameters base_query_parameters = 1;
+}
+
+message GetCallRatesResponse {
+    jaeger.api_v2.metrics.MetricFamily metric_family = 1;
+}
+
+message GetErrorRatesRequest {
+    MetricsBaseQueryParameters base_query_parameters = 1;
+}
+
+message GetErrorRatesResponse {
+    jaeger.api_v2.metrics.MetricFamily metric_family = 1;
+}
+
+message GetMinStepDurationRequest {
+}
+
+message GetMinStepDurationResponse {
+    google.protobuf.Duration min_step = 1;
+}
+
 // empty; extensible in the future
 message CapabilitiesRequest {
 
@@ -183,6 +234,7 @@ message CapabilitiesResponse {
     bool archiveSpanReader = 1;
     bool archiveSpanWriter = 2;
     bool streamingSpanWriter = 3;
+    bool metricsReader = 4;
 }
 
 service PluginCapabilities {