[exporter/loadbalacing] Refactor how metrics are split and then re-joined after load-balacing

.chloggen/loadbalancer_exporter_refactor.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: loadbalancerexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Refactors how the load balancing exporter splits metrics
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [32513]
+
+# (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: All splitting is *behaviorally*, the same. However, the `resource` routingID now uses the `internal/exp/metrics/identity` package to generate the load balancing key, instead of bespoke code. This means that when upgrading to this version your routes for specific metric groupings could change. However, this will be stable and all future metrics will follow the new routing
+
+# 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: [user]

cmd/configschema/go.mod

@@ -564,6 +564,7 @@ require (
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/aws/xray v0.101.0 // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/collectd v0.101.0 // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/common v0.101.0 // indirect
+	github.com/open-telemetry/opentelemetry-collector-contrib/internal/exp/metrics v0.101.0 // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/kafka v0.101.0 // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/sharedcomponent v0.101.0 // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/experimentalmetricmetadata v0.101.0 // indirect
@@ -1228,3 +1229,5 @@ replace github.com/open-telemetry/opentelemetry-collector-contrib/extension/sumo
 replace github.com/open-telemetry/opentelemetry-collector-contrib/receiver/splunkenterprisereceiver => ../../receiver/splunkenterprisereceiver
 
 replace github.com/open-telemetry/opentelemetry-collector-contrib/pkg/sampling => ../../pkg/sampling
+
+replace github.com/open-telemetry/opentelemetry-collector-contrib/internal/exp/metrics => ../../internal/exp/metrics

exporter/loadbalancingexporter/config.go

@@ -19,6 +19,13 @@ const (
 	resourceRouting
 )
 
+const (
+	svcRoutingStr        = "service"
+	traceIDRoutingStr    = "traceID"
+	metricNameRoutingStr = "metric"
+	resourceRoutingStr   = "resource"
+)
+
 // Config defines configuration for the exporter.
 type Config struct {
 	Protocol   Protocol         `mapstructure:"protocol"`

exporter/loadbalancingexporter/go.mod

@@ -6,7 +6,11 @@ require (
 	github.com/aws/aws-sdk-go-v2/config v1.27.16
 	github.com/aws/aws-sdk-go-v2/service/servicediscovery v1.29.10
 	github.com/aws/smithy-go v1.20.2
+	github.com/json-iterator/go v1.1.12
+	github.com/open-telemetry/opentelemetry-collector-contrib/internal/exp/metrics v0.101.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/batchpersignal v0.101.0
+	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/golden v0.101.0
+	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/pdatatest v0.101.0
 	github.com/stretchr/testify v1.9.0
 	go.opencensus.io v0.24.0
 	go.opentelemetry.io/collector/component v0.101.1-0.20240529223953-eaab76e46d38
@@ -22,6 +26,7 @@ require (
 	go.uber.org/goleak v1.3.0
 	go.uber.org/multierr v1.11.0
 	go.uber.org/zap v1.27.0
+	gopkg.in/yaml.v2 v2.4.0
 	k8s.io/api v0.29.3
 	k8s.io/apimachinery v0.29.3
 	k8s.io/client-go v0.29.3
@@ -69,7 +74,6 @@ require (
 	github.com/imdario/mergo v0.3.6 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
-	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.17.4 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect
 	github.com/knadh/koanf/providers/confmap v0.1.0 // indirect
@@ -82,6 +86,7 @@ require (
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/mostynb/go-grpc-compression v1.2.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/pdatautil v0.101.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
@@ -149,7 +154,6 @@ require (
 	google.golang.org/grpc v1.64.0 // indirect
 	google.golang.org/protobuf v1.34.1 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
-	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/klog/v2 v2.110.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
@@ -168,3 +172,11 @@ retract (
 
 // ambiguous import: found package cloud.google.com/go/compute/metadata in multiple modules
 replace cloud.google.com/go v0.65.0 => cloud.google.com/go v0.110.10
+
+replace github.com/open-telemetry/opentelemetry-collector-contrib/pkg/pdatautil => ../../pkg/pdatautil
+
+replace github.com/open-telemetry/opentelemetry-collector-contrib/pkg/pdatatest => ../../pkg/pdatatest
+
+replace github.com/open-telemetry/opentelemetry-collector-contrib/pkg/golden => ../../pkg/golden
+
+replace github.com/open-telemetry/opentelemetry-collector-contrib/internal/exp/metrics => ../../internal/exp/metrics

exporter/loadbalancingexporter/helpers.go

@@ -4,7 +4,6 @@
 package loadbalancingexporter // import "github.com/open-telemetry/opentelemetry-collector-contrib/exporter/loadbalancingexporter"
 
 import (
-	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.opentelemetry.io/collector/pdata/ptrace"
 )
 
@@ -13,9 +12,3 @@ func mergeTraces(t1 ptrace.Traces, t2 ptrace.Traces) ptrace.Traces {
 	t2.ResourceSpans().MoveAndAppendTo(t1.ResourceSpans())
 	return t1
 }
-
-// mergeMetrics concatenates two pmetric.Metrics into a single pmetric.Metrics.
-func mergeMetrics(m1 pmetric.Metrics, m2 pmetric.Metrics) pmetric.Metrics {
-	m2.ResourceMetrics().MoveAndAppendTo(m1.ResourceMetrics())
-	return m1
-}

exporter/loadbalancingexporter/helpers_test.go

@@ -7,7 +7,6 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
-	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.opentelemetry.io/collector/pdata/ptrace"
 	conventions "go.opentelemetry.io/collector/semconv/v1.6.1"
 )
@@ -66,60 +65,6 @@ func TestMergeTraces(t *testing.T) {
 	require.Equal(t, expectedTraces, mergedTraces)
 }
 
-func TestMergeMetricsTwoEmpty(t *testing.T) {
-	expectedEmpty := pmetric.NewMetrics()
-	metric1 := pmetric.NewMetrics()
-	metric2 := pmetric.NewMetrics()
-
-	mergedMetrics := mergeMetrics(metric1, metric2)
-
-	require.Equal(t, expectedEmpty, mergedMetrics)
-}
-
-func TestMergeMetricsSingleEmpty(t *testing.T) {
-	expectedMetrics := simpleMetricsWithResource()
-
-	metric1 := pmetric.NewMetrics()
-	metric2 := simpleMetricsWithResource()
-
-	mergedMetrics := mergeMetrics(metric1, metric2)
-
-	require.Equal(t, expectedMetrics, mergedMetrics)
-}
-
-func TestMergeMetrics(t *testing.T) {
-	expectedMetrics := pmetric.NewMetrics()
-	expectedMetrics.ResourceMetrics().EnsureCapacity(3)
-	ametrics := expectedMetrics.ResourceMetrics().AppendEmpty()
-	ametrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-1")
-	ametrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m1")
-	bmetrics := expectedMetrics.ResourceMetrics().AppendEmpty()
-	bmetrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-2")
-	bmetrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m1")
-	cmetrics := expectedMetrics.ResourceMetrics().AppendEmpty()
-	cmetrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-3")
-	cmetrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m2")
-
-	metric1 := pmetric.NewMetrics()
-	metric1.ResourceMetrics().EnsureCapacity(2)
-	m1ametrics := metric1.ResourceMetrics().AppendEmpty()
-	m1ametrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-1")
-	m1ametrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m1")
-	m1bmetrics := metric1.ResourceMetrics().AppendEmpty()
-	m1bmetrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-2")
-	m1bmetrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m1")
-
-	metric2 := pmetric.NewMetrics()
-	metric2.ResourceMetrics().EnsureCapacity(1)
-	m2cmetrics := metric2.ResourceMetrics().AppendEmpty()
-	m2cmetrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, "service-name-3")
-	m2cmetrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName("m2")
-
-	mergedMetrics := mergeMetrics(metric1, metric2)
-
-	require.Equal(t, expectedMetrics, mergedMetrics)
-}
-
 func benchMergeTraces(b *testing.B, tracesCount int) {
 	traces1 := ptrace.NewTraces()
 	traces2 := ptrace.NewTraces()
@@ -146,30 +91,3 @@ func BenchmarkMergeTraces_X500(b *testing.B) {
 func BenchmarkMergeTraces_X1000(b *testing.B) {
 	benchMergeTraces(b, 1000)
 }
-
-func benchMergeMetrics(b *testing.B, metricsCount int) {
-	metrics1 := pmetric.NewMetrics()
-	metrics2 := pmetric.NewMetrics()
-
-	for i := 0; i < metricsCount; i++ {
-		appendSimpleMetricWithID(metrics2.ResourceMetrics().AppendEmpty(), "metrics-2")
-	}
-
-	b.ResetTimer()
-
-	for i := 0; i < b.N; i++ {
-		mergeMetrics(metrics1, metrics2)
-	}
-}
-
-func BenchmarkMergeMetrics_X100(b *testing.B) {
-	benchMergeMetrics(b, 100)
-}
-
-func BenchmarkMergeMetrics_X500(b *testing.B) {
-	benchMergeMetrics(b, 500)
-}
-
-func BenchmarkMergeMetrics_X1000(b *testing.B) {
-	benchMergeMetrics(b, 1000)
-}