[cmd/telemetrygen] Add exemplars support for telemetrygen

.chloggen/add-traceid-spanid-exemplars-telemetrygen.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'enhancement'
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: cmd/telemetrygen
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add support for adding spanID and traceID as exemplars to datapoints generated by telemetrygen
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [33320]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

cmd/telemetrygen/internal/common/validate.go

@@ -0,0 +1,41 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package common
+
+import (
+	"encoding/hex"
+	"fmt"
+)
+
+var (
+	errInvalidTraceIDLenght = fmt.Errorf("TraceID must be a 32 character hex string, like: 'ae87dadd90e9935a4bc9660628efd569'")
+	errInvalidSpanIDLenght  = fmt.Errorf("SpanID must be a 16 character hex string, like: '5828fa4960140870'")
+	errInvalidTraceID       = fmt.Errorf("failed to create traceID byte array from the given traceID, make sure the traceID is a hex representation of a [16]byte, like: 'ae87dadd90e9935a4bc9660628efd569'")
+	errInvalidSpanID        = fmt.Errorf("failed to create SpanID byte array from the given SpanID, make sure the SpanID is a hex representation of a [8]byte, like: '5828fa4960140870'")
+)
+
+func ValidateTraceID(traceID string) error {
+	if len(traceID) != 32 {
+		return errInvalidTraceIDLenght
+	}
+
+	_, err := hex.DecodeString(traceID)
+	if err != nil {
+		return errInvalidTraceID
+	}
+
+	return nil
+}
+
+func ValidateSpanID(spanID string) error {
+	if len(spanID) != 16 {
+		return errInvalidSpanIDLenght
+	}
+	_, err := hex.DecodeString(spanID)
+	if err != nil {
+		return errInvalidSpanID
+	}
+
+	return nil
+}

cmd/telemetrygen/internal/common/validate_test.go

@@ -0,0 +1,70 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package common
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValidateTraceID(t *testing.T) {
+	tests := []struct {
+		name     string
+		traceID  string
+		expected error
+	}{
+		{
+			name:     "Valid",
+			traceID:  "ae87dadd90e9935a4bc9660628efd569",
+			expected: nil,
+		},
+		{
+			name:     "InvalidLength",
+			traceID:  "invalid-length",
+			expected: errInvalidTraceIDLenght,
+		},
+		{
+			name:     "InvalidTraceID",
+			traceID:  "zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz",
+			expected: errInvalidTraceID,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ValidateTraceID(tt.traceID)
+			assert.ErrorIs(t, err, tt.expected)
+		})
+	}
+}
+
+func TestValidateSpanID(t *testing.T) {
+	tests := []struct {
+		name     string
+		spanID   string
+		expected error
+	}{
+		{
+			name:     "Valid",
+			spanID:   "5828fa4960140870",
+			expected: nil,
+		},
+		{
+			name:     "InvalidLength",
+			spanID:   "invalid-length",
+			expected: errInvalidSpanIDLenght,
+		},
+		{
+			name:     "InvalidTraceID",
+			spanID:   "zzzzzzzzzzzzzzzz",
+			expected: errInvalidSpanID,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ValidateSpanID(tt.spanID)
+			assert.ErrorIs(t, err, tt.expected)
+		})
+	}
+}

cmd/telemetrygen/internal/logs/config.go

@@ -4,8 +4,6 @@
 package logs
 
 import (
-	"encoding/hex"
-
 	"github.com/spf13/pflag"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/cmd/telemetrygen/internal/common"
@@ -39,23 +37,14 @@ func (c *Config) Flags(fs *pflag.FlagSet) {
 // Validate validates the test scenario parameters.
 func (c *Config) Validate() error {
 	if c.TraceID != "" {
-		if len(c.TraceID) != 32 {
-			return errInvalidTraceIDLenght
-		}
-
-		_, err := hex.DecodeString(c.TraceID)
-		if err != nil {
-			return errInvalidTraceID
+		if err := common.ValidateTraceID(c.TraceID); err != nil {
+			return err
 		}
 	}
 
 	if c.SpanID != "" {
-		if len(c.SpanID) != 16 {
-			return errInvalidSpanIDLenght
-		}
-		_, err := hex.DecodeString(c.SpanID)
-		if err != nil {
-			return errInvalidSpanID
+		if err := common.ValidateSpanID(c.SpanID); err != nil {
+			return err
 		}
 	}
 

cmd/telemetrygen/internal/logs/logs.go

@@ -18,13 +18,6 @@ import (
 	"github.com/open-telemetry/opentelemetry-collector-contrib/cmd/telemetrygen/internal/common"
 )
 
-var (
-	errInvalidTraceIDLenght = fmt.Errorf("TraceID must be a 32 character hex string, like: 'ae87dadd90e9935a4bc9660628efd569'")
-	errInvalidSpanIDLenght  = fmt.Errorf("SpanID must be a 16 character hex string, like: '5828fa4960140870'")
-	errInvalidTraceID       = fmt.Errorf("failed to create traceID byte array from the given traceID, make sure the traceID is a hex representation of a [16]byte, like: 'ae87dadd90e9935a4bc9660628efd569'")
-	errInvalidSpanID        = fmt.Errorf("failed to create SpanID byte array from the given SpanID, make sure the SpanID is a hex representation of a [8]byte, like: '5828fa4960140870'")
-)
-
 // Start starts the log telemetry generator
 func Start(cfg *Config) error {
 	logger, err := common.CreateLogger(cfg.SkipSettingGRPCLogger)

cmd/telemetrygen/internal/metrics/config.go

@@ -15,6 +15,8 @@ type Config struct {
 	NumMetrics int
 	MetricName string
 	MetricType metricType
+	SpanID     string
+	TraceID    string
 }
 
 // Flags registers config flags.
@@ -29,4 +31,25 @@ func (c *Config) Flags(fs *pflag.FlagSet) {
 
 	fs.Var(&c.MetricType, "metric-type", "Metric type enum. must be one of 'Gauge' or 'Sum'")
 	fs.IntVar(&c.NumMetrics, "metrics", 1, "Number of metrics to generate in each worker (ignored if duration is provided)")
+
+	fs.StringVar(&c.TraceID, "trace-id", "", "TraceID to use as exemplar")
+	fs.StringVar(&c.SpanID, "span-id", "", "SpanID to use as exemplar")
+
+}
+
+// Validate validates the test scenario parameters.
+func (c *Config) Validate() error {
+	if c.TraceID != "" {
+		if err := common.ValidateTraceID(c.TraceID); err != nil {
+			return err
+		}
+	}
+
+	if c.SpanID != "" {
+		if err := common.ValidateSpanID(c.SpanID); err != nil {
+			return err
+		}
+	}
+
+	return nil
 }

cmd/telemetrygen/internal/metrics/metrics.go

@@ -5,6 +5,7 @@ package metrics
 
 import (
 	"context"
+	"encoding/hex"
 	"fmt"
 	"sync"
 	"sync/atomic"
@@ -14,6 +15,7 @@ import (
 	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
 	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp"
 	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 	"go.opentelemetry.io/otel/sdk/resource"
 	"go.uber.org/zap"
 	"golang.org/x/time/rate"
@@ -95,6 +97,7 @@ func Run(c *Config, exp func() (sdkmetric.Exporter, error), logger *zap.Logger)
 			numMetrics:     c.NumMetrics,
 			metricName:     c.MetricName,
 			metricType:     c.MetricType,
+			exemplars:      exemplarsFromConfig(c),
 			limitPerSecond: limit,
 			totalDuration:  c.TotalDuration,
 			running:        running,
@@ -112,3 +115,31 @@ func Run(c *Config, exp func() (sdkmetric.Exporter, error), logger *zap.Logger)
 	wg.Wait()
 	return nil
 }
+
+func exemplarsFromConfig(c *Config) []metricdata.Exemplar[int64] {
+	if c.TraceID != "" || c.SpanID != "" {
+		var exemplars []metricdata.Exemplar[int64]
+
+		exemplar := metricdata.Exemplar[int64]{
+			Value: 1,
+			Time:  time.Now(),
+		}
+
+		if c.TraceID != "" {
+			// we validated this already during the Validate() function for config
+			// nolint: errcheck
+			traceID, _ := hex.DecodeString(c.TraceID)
+			exemplar.TraceID = traceID
+		}
+
+		if c.SpanID != "" {
+			// we validated this already during the Validate() function for config
+			// nolint: errcheck
+			spanID, _ := hex.DecodeString(c.SpanID)
+			exemplar.SpanID = spanID
+		}
+
+		return append(exemplars, exemplar)
+	}
+	return nil
+}