refact(trace): Move custom trace attributes to a trace package

Signed-off-by: Vincent Mercier <vmercier@gmail.com>

internal/app/ec2/ec2.go

@@ -7,9 +7,9 @@ import (
 
 	aws_ec2 "github.com/aws/aws-sdk-go-v2/service/ec2"
 	aws_ec2_types "github.com/aws/aws-sdk-go-v2/service/ec2/types"
+	"github.com/qonto/prometheus-rds-exporter/internal/app/trace"
 	converter "github.com/qonto/prometheus-rds-exporter/internal/app/unit"
 	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 )
 
@@ -67,7 +67,7 @@ func (e *EC2Fetcher) GetDBInstanceTypeInformation(instanceTypes []string) (Metri
 		_, instanceTypeSpan := tracer.Start(ctx, "collect-ec2-instance-types-metrics")
 		defer instanceTypeSpan.End()
 
-		instanceTypeSpan.SetAttributes(attribute.Int("com.qonto.prometheus_rds_exporter.instance-types-count", len(instances)))
+		instanceTypeSpan.SetAttributes(trace.AWSInstanceTypesCount(int64(len(instances))))
 
 		// Remove "db." prefix from instance types
 		instanceTypesToFetch := make([]aws_ec2_types.InstanceType, len(instances))

internal/app/servicequotas/servicequotas.go

@@ -7,9 +7,9 @@ import (
 	"fmt"
 
 	aws_servicequotas "github.com/aws/aws-sdk-go-v2/service/servicequotas"
+	"github.com/qonto/prometheus-rds-exporter/internal/app/trace"
 	converter "github.com/qonto/prometheus-rds-exporter/internal/app/unit"
 	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"golang.org/x/exp/slog"
 )
@@ -67,7 +67,7 @@ func (s *serviceQuotaFetcher) getQuota(serviceCode string, quotaCode string) (fl
 	_, span := tracer.Start(s.ctx, "get-quota")
 	defer span.End()
 
-	span.SetAttributes(attribute.String("com.qonto.prometheus_rds_exporter.aws.quota.service_code", serviceCode), attribute.String("com.qonto.prometheus_rds_exporter.aws.quota.code", quotaCode))
+	span.SetAttributes(trace.AWSQuotaServiceCode(serviceCode), trace.AWSQuotaCode(quotaCode))
 
 	params := &aws_servicequotas.GetServiceQuotaInput{
 		ServiceCode: &serviceCode,

internal/app/trace/attibute.go

@@ -0,0 +1,28 @@
+// Package trace provides OTEL tracing resources
+package trace
+
+import "go.opentelemetry.io/otel/attribute"
+
+// Attribute Naming convention
+//
+// Use namespacing to avoid name clashes. Delimit the namespaces using a dot character. For example service.version denotes the service version where service is the namespace and version is an attribute in that namespace.
+// For each multi-word dot-delimited component of the attribute name separate the words by underscores (i.e. use snake_case).
+// See https://opentelemetry.io/docs/specs/semconv/general/attribute-naming/
+
+const (
+	AWSServiceCodeOtelKey    = attribute.Key("qonto.prometheus_rds_exporter.aws.quota.service_code")
+	AWSQuotaCodeOtelKey      = attribute.Key("qonto.prometheus_rds_exporter.aws.quota.code")
+	AWSInstanceTypesCountKey = attribute.Key("qonto.prometheus_rds_exporter.aws.instance-types-count")
+)
+
+func AWSQuotaServiceCode(val string) attribute.KeyValue {
+	return AWSServiceCodeOtelKey.String(val)
+}
+
+func AWSQuotaCode(val string) attribute.KeyValue {
+	return AWSQuotaCodeOtelKey.String(val)
+}
+
+func AWSInstanceTypesCount(val int64) attribute.KeyValue {
+	return AWSInstanceTypesCountKey.Int64(val)
+}

internal/app/trace/attibute_test.go

@@ -0,0 +1,43 @@
+package trace_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/qonto/prometheus-rds-exporter/internal/app/trace"
+	"go.opentelemetry.io/otel/attribute"
+)
+
+func TestOtelKeys(t *testing.T) {
+	type test struct {
+		name  string
+		want  attribute.KeyValue
+		key   string
+		value any
+	}
+
+	tests := []test{
+		{"QuotaServiceCode", trace.AWSQuotaServiceCode("unittest"), "qonto.prometheus_rds_exporter.aws.quota.service_code", "unittest"},
+		{"QuotaCode", trace.AWSQuotaCode("unittest"), "qonto.prometheus_rds_exporter.aws.quota.code", "unittest"},
+		{"InstanceTypesCount", trace.AWSInstanceTypesCount(42), "qonto.prometheus_rds_exporter.aws.instance-types-count", int64(42)},
+	}
+
+	for _, tc := range tests {
+		if !reflect.DeepEqual(string(tc.want.Key), tc.key) {
+			t.Fatalf("%s: expected key: %v, got: %v", tc.name, tc.want.Key, tc.key)
+		}
+
+		switch tc.value.(type) {
+		case string:
+			if !reflect.DeepEqual(tc.want.Value.AsString(), tc.value) {
+				t.Fatalf("%s: expected value: %v, got: %v", tc.name, tc.want.Value.AsString(), tc.value)
+			}
+		case int64:
+			if !reflect.DeepEqual(tc.want.Value.AsInt64(), tc.value) {
+				t.Fatalf("%s: expected value: %v, got: %v", tc.name, tc.want.Value.AsInt64(), tc.value)
+			}
+		default:
+			t.Fatalf("%s: %s type is not implemented. Add it to the test suite", tc.name, reflect.TypeOf(tc.value))
+		}
+	}
+}