From c137790c3362c9450dc3d7b0aa55f5691b717423 Mon Sep 17 00:00:00 2001
From: Ragot Geoffrey <geoffrey.ragot@gmail.com>
Date: Fri, 18 Nov 2022 09:14:03 +0100
Subject: [PATCH] feat(telemetry): add resource attributes

---
 sharedotlp/pkg/sharedotlptraces/cli.go    |  6 ++++
 sharedotlp/pkg/sharedotlptraces/traces.go | 38 +++++++++++++++--------
 2 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/sharedotlp/pkg/sharedotlptraces/cli.go b/sharedotlp/pkg/sharedotlptraces/cli.go
index ca78cae..d98ee4c 100644
--- a/sharedotlp/pkg/sharedotlptraces/cli.go
+++ b/sharedotlp/pkg/sharedotlptraces/cli.go
@@ -16,6 +16,8 @@ const (
 	OtelTracesExporterOTLPModeFlag       = "otel-traces-exporter-otlp-mode"
 	OtelTracesExporterOTLPEndpointFlag   = "otel-traces-exporter-otlp-endpoint"
 	OtelTracesExporterOTLPInsecureFlag   = "otel-traces-exporter-otlp-insecure"
+	OtelResourceAttributes               = "otel-resource-attributes"
+	OtelServiceName                      = "otel-service-name"
 )
 
 func InitOTLPTracesFlags(flags *flag.FlagSet) {
@@ -28,6 +30,8 @@ func InitOTLPTracesFlags(flags *flag.FlagSet) {
 	flags.String(OtelTracesExporterOTLPModeFlag, "grpc", "OpenTelemetry traces OTLP exporter mode (grpc|http)")
 	flags.String(OtelTracesExporterOTLPEndpointFlag, "", "OpenTelemetry traces grpc endpoint")
 	flags.Bool(OtelTracesExporterOTLPInsecureFlag, false, "OpenTelemetry traces grpc insecure")
+	flags.String(OtelServiceName, "", "OpenTelemetry service name")
+	flags.StringSlice(OtelResourceAttributes, []string{}, "Additional OTLP resource attributes")
 }
 
 func CLITracesModule(v *viper.Viper) fx.Option {
@@ -55,6 +59,8 @@ func CLITracesModule(v *viper.Viper) fx.Option {
 					Insecure: v.GetBool(OtelTracesExporterOTLPInsecureFlag),
 				}
 			}(),
+			ServiceName:        v.GetString(OtelServiceName),
+			ResourceAttributes: v.GetStringSlice(OtelResourceAttributes),
 		})
 	}
 	return fx.Options()
diff --git a/sharedotlp/pkg/sharedotlptraces/traces.go b/sharedotlp/pkg/sharedotlptraces/traces.go
index a0a9931..fc4f007 100644
--- a/sharedotlp/pkg/sharedotlptraces/traces.go
+++ b/sharedotlp/pkg/sharedotlptraces/traces.go
@@ -2,10 +2,13 @@ package sharedotlptraces
 
 import (
 	"context"
+	"fmt"
+	"strings"
 
 	sharedotlp "github.com/formancehq/go-libs/sharedotlp/pkg"
 	"go.opentelemetry.io/contrib/propagators/b3"
 	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/exporters/jaeger"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
@@ -37,11 +40,12 @@ type OTLPConfig struct {
 }
 
 type ModuleConfig struct {
-	Exporter     string
-	Batch        bool
-	JaegerConfig *JaegerConfig
-	OTLPConfig   *OTLPConfig
-	Resource     *resource.Resource
+	Exporter           string
+	Batch              bool
+	JaegerConfig       *JaegerConfig
+	OTLPConfig         *OTLPConfig
+	ResourceAttributes []string
+	ServiceName        string
 }
 
 func ProvideTracerProviderOption(v any, annotations ...fx.Annotation) fx.Option {
@@ -49,17 +53,25 @@ func ProvideTracerProviderOption(v any, annotations ...fx.Annotation) fx.Option
 	return fx.Provide(fx.Annotate(v, annotations...))
 }
 
+func loadResource(cfg ModuleConfig) (*resource.Resource, error) {
+	defaultResource := resource.Default()
+	attributes := make([]attribute.KeyValue, 0)
+	attributes = append(attributes, attribute.String("service.name", cfg.ServiceName))
+	for _, ra := range cfg.ResourceAttributes {
+		parts := strings.SplitN(ra, "=", 2)
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("malformed otlp attribute: %s", ra)
+		}
+		attributes = append(attributes, attribute.String(parts[0], parts[1]))
+	}
+	return resource.Merge(defaultResource, resource.NewSchemaless(attributes...))
+}
+
 func TracesModule(cfg ModuleConfig) fx.Option {
 	options := make([]fx.Option, 0)
 	options = append(options,
-		fx.Provide(func() (*resource.Resource, error) {
-			defaultResource := resource.Default()
-			if cfg.Resource == nil {
-				return defaultResource, nil
-			}
-			return resource.Merge(defaultResource, cfg.Resource)
-		}),
-		fx.Supply(resource.Default()),
+		fx.Supply(cfg),
+		fx.Provide(loadResource),
 		fx.Provide(func(tp *tracesdk.TracerProvider) trace.TracerProvider { return tp }),
 		fx.Provide(fx.Annotate(func(options ...tracesdk.TracerProviderOption) *tracesdk.TracerProvider {
 			return tracesdk.NewTracerProvider(options...)