go.opentelemetry.io/proto/otlp v1.9.0: v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE

# OpenTelemetry OTLP AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE Semantics

A search for `go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE` in `pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0` returned `NO_SAFE_MATCH`.

This sample verifies the enum constant, string mapping, metric container integration, binary protobuf serialization, and protojson serialization for `AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE`.

## Observed Behavior

1. **Enum Value and String Mapping**:
   - `AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE` has integer value 2 and protoreflect enum number 2.
   - Calling `.String()` yields `"AGGREGATION_TEMPORALITY_CUMULATIVE"`.
   - `AggregationTemporality_name[2]` returns `"AGGREGATION_TEMPORALITY_CUMULATIVE"`.
   - `AggregationTemporality_value["AGGREGATION_TEMPORALITY_CUMULATIVE"]` returns 2.
   - `Enum()` returns a pointer referencing the enum constant.

2. **Metric Type Integration (`Sum`, `Histogram`, `ExponentialHistogram`)**:
   - `Sum.AggregationTemporality`, `Histogram.AggregationTemporality`, and `ExponentialHistogram.AggregationTemporality` store how metric values aggregate over time.
   - `GetAggregationTemporality()` returns `AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE` when set, and defaults safely to `AGGREGATION_TEMPORALITY_UNSPECIFIED` (0) on nil or uninitialized structs.

3. **Protobuf Binary Wire Format**:
   - Serializing a `Metric` containing a `Sum` or `Histogram` with cumulative temporality preserves the enum value across `proto.Marshal` and `proto.Unmarshal`.

4. **JSON Serialization (`protojson`)**:
   - Standard serialization renders the enum as the string `"AGGREGATION_TEMPORALITY_CUMULATIVE"`.
   - With `protojson.MarshalOptions{UseEnumNumbers: true}`, the enum is serialized numerically (`2`).
   - Both formats round-trip cleanly back to `AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE`.

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE in pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0
Demonstrate these symbols/APIs:
  - go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:1095233a6d8f8ed4c5cb0ed6024a37089d3588e57f6914093247c72d994c989e","contract":["AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE has constant int32 value 2, protoreflect Number 2, string representation AGGREGATION_TEMPORALITY_CUMULATIVE, and consistent name/value map lookups.","Sum, Histogram, and ExponentialHistogram metric structs configure AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE and retrieve it via GetAggregationTemporality, defaulting to UNSPECIFIED when nil.","AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE persists across protobuf binary marshaling and unmarshaling in Metric messages containing Sum and Histogram payloads.","AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE serializes to JSON as enum string and enum number formats and round-trips correctly via protojson."],"goal":"verify go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE in pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0","symbols":["go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE"],"verifierAdapter":"golang@1"}

module example.com/otlp-cumulative

go 1.23.0

require (
	go.opentelemetry.io/proto/otlp v1.9.0
	google.golang.org/protobuf v1.36.10
)

github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
go.opentelemetry.io/proto/otlp v1.9.0 h1:l706jCMITVouPOqEnii2fIAuO3IVGBRPV5ICjceRb/A=
go.opentelemetry.io/proto/otlp v1.9.0/go.mod h1:xE+Cx5E/eEHw+ISFkwPLwCZefwVjY+pqKg1qcK03+/4=
google.golang.org/protobuf v1.36.10 h1:AYd7cD/uASjIL6Q9LiTjz8JLcrh/88q5UObnmY3aOOE=
google.golang.org/protobuf v1.36.10/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=

package main

import (
	"fmt"

	metricspb "go.opentelemetry.io/proto/otlp/metrics/v1"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

// BuildCumulativeSumMetric creates a Metric containing a Sum with CUMULATIVE temporality.
func BuildCumulativeSumMetric(name string, value int64) *metricspb.Metric {
	return &metricspb.Metric{
		Name: name,
		Data: &metricspb.Metric_Sum{
			Sum: &metricspb.Sum{
				AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
				IsMonotonic:            true,
				DataPoints: []*metricspb.NumberDataPoint{
					{
						Value: &metricspb.NumberDataPoint_AsInt{
							AsInt: value,
						},
					},
				},
			},
		},
	}
}

// BuildCumulativeHistogramMetric creates a Metric containing a Histogram with CUMULATIVE temporality.
func BuildCumulativeHistogramMetric(name string, count uint64, sum float64) *metricspb.Metric {
	return &metricspb.Metric{
		Name: name,
		Data: &metricspb.Metric_Histogram{
			Histogram: &metricspb.Histogram{
				AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
				DataPoints: []*metricspb.HistogramDataPoint{
					{
						Count: count,
						Sum:   &sum,
					},
				},
			},
		},
	}
}

// EncodeMetricBinary serializes an OTLP Metric into protobuf binary format.
func EncodeMetricBinary(m *metricspb.Metric) ([]byte, error) {
	return proto.Marshal(m)
}

// DecodeMetricBinary deserializes an OTLP Metric from protobuf binary format.
func DecodeMetricBinary(data []byte) (*metricspb.Metric, error) {
	var m metricspb.Metric
	if err := proto.Unmarshal(data, &m); err != nil {
		return nil, err
	}
	return &m, nil
}

// EncodeMetricJSON serializes an OTLP Metric into protojson format.
func EncodeMetricJSON(m *metricspb.Metric, useEnumNumbers bool) ([]byte, error) {
	opts := protojson.MarshalOptions{
		UseEnumNumbers: useEnumNumbers,
	}
	return opts.Marshal(m)
}

// DecodeMetricJSON deserializes an OTLP Metric from protojson format.
func DecodeMetricJSON(data []byte) (*metricspb.Metric, error) {
	var m metricspb.Metric
	if err := protojson.Unmarshal(data, &m); err != nil {
		return nil, err
	}
	return &m, nil
}

func main() {
	m := BuildCumulativeSumMetric("http_requests_total", 1024)
	temporality := m.GetSum().GetAggregationTemporality()
	fmt.Printf("Metric: %s, Temporality: %s (value=%d)\n", m.GetName(), temporality.String(), int32(temporality))
}

{
  "schemaVersion": 1,
  "goal": "verify go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE in pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/proto/otlp@v1.9.0"
  ],
  "symbols": [
    "go.opentelemetry.io/proto/otlp/metrics/v1.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE"
  ]
}

package main

import (
	"fmt"
	"os"
	"strings"

	metricspb "go.opentelemetry.io/proto/otlp/metrics/v1"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

func main() {
	// Assertion 1: AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE has constant int32 value 2, protoreflect Number 2, string representation "AGGREGATION_TEMPORALITY_CUMULATIVE", and consistent name/value map lookups.
	{
		cum := metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE

		if int32(cum) != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: expected int32 value 2 for CUMULATIVE, got %d\n", int32(cum))
			os.Exit(1)
		}

		if cum.Number() != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: expected protoreflect Number 2 for CUMULATIVE, got %d\n", cum.Number())
			os.Exit(1)
		}

		if cum.String() != "AGGREGATION_TEMPORALITY_CUMULATIVE" {
			fmt.Fprintf(os.Stderr, "FAIL: expected String() 'AGGREGATION_TEMPORALITY_CUMULATIVE', got %s\n", cum.String())
			os.Exit(1)
		}

		if name, ok := metricspb.AggregationTemporality_name[2]; !ok || name != "AGGREGATION_TEMPORALITY_CUMULATIVE" {
			fmt.Fprintf(os.Stderr, "FAIL: name map lookup failed: ok=%v name=%s\n", ok, name)
			os.Exit(1)
		}

		if val, ok := metricspb.AggregationTemporality_value["AGGREGATION_TEMPORALITY_CUMULATIVE"]; !ok || val != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: value map lookup failed: ok=%v val=%d\n", ok, val)
			os.Exit(1)
		}

		if enumPtr := cum.Enum(); enumPtr == nil || *enumPtr != cum {
			fmt.Fprintf(os.Stderr, "FAIL: Enum() pointer value invalid\n")
			os.Exit(1)
		}
	}

	// Assertion 2: Sum, Histogram, and ExponentialHistogram metric structs configure AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE and retrieve it via GetAggregationTemporality, defaulting to UNSPECIFIED when nil.
	{
		var nilSum *metricspb.Sum
		if nilSum.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_UNSPECIFIED {
			fmt.Fprintf(os.Stderr, "FAIL: nil Sum should return UNSPECIFIED, got %v\n", nilSum.GetAggregationTemporality())
			os.Exit(1)
		}

		var nilHist *metricspb.Histogram
		if nilHist.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_UNSPECIFIED {
			fmt.Fprintf(os.Stderr, "FAIL: nil Histogram should return UNSPECIFIED, got %v\n", nilHist.GetAggregationTemporality())
			os.Exit(1)
		}

		var nilExpHist *metricspb.ExponentialHistogram
		if nilExpHist.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_UNSPECIFIED {
			fmt.Fprintf(os.Stderr, "FAIL: nil ExponentialHistogram should return UNSPECIFIED, got %v\n", nilExpHist.GetAggregationTemporality())
			os.Exit(1)
		}

		sum := &metricspb.Sum{
			AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
			IsMonotonic:            true,
		}
		if sum.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: sum.GetAggregationTemporality() expected CUMULATIVE, got %v\n", sum.GetAggregationTemporality())
			os.Exit(1)
		}

		hist := &metricspb.Histogram{
			AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
		}
		if hist.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: hist.GetAggregationTemporality() expected CUMULATIVE, got %v\n", hist.GetAggregationTemporality())
			os.Exit(1)
		}

		expHist := &metricspb.ExponentialHistogram{
			AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
		}
		if expHist.GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: expHist.GetAggregationTemporality() expected CUMULATIVE, got %v\n", expHist.GetAggregationTemporality())
			os.Exit(1)
		}
	}

	// Assertion 3: AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE persists across protobuf binary marshaling and unmarshaling in Metric messages containing Sum and Histogram payloads.
	{
		sumMetric := &metricspb.Metric{
			Name: "system_cpu_time",
			Data: &metricspb.Metric_Sum{
				Sum: &metricspb.Sum{
					AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
					IsMonotonic:            true,
					DataPoints: []*metricspb.NumberDataPoint{
						{
							Value: &metricspb.NumberDataPoint_AsInt{
								AsInt: 4096,
							},
						},
					},
				},
			},
		}

		sumData, err := proto.Marshal(sumMetric)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: proto.Marshal sumMetric failed: %v\n", err)
			os.Exit(1)
		}

		var decodedSumMetric metricspb.Metric
		if err := proto.Unmarshal(sumData, &decodedSumMetric); err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: proto.Unmarshal sumMetric failed: %v\n", err)
			os.Exit(1)
		}

		if decodedSumMetric.GetSum().GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: decoded sum temporality mismatch: expected CUMULATIVE, got %s\n", decodedSumMetric.GetSum().GetAggregationTemporality())
			os.Exit(1)
		}

		histSum := 55.5
		histMetric := &metricspb.Metric{
			Name: "http_server_duration_seconds",
			Data: &metricspb.Metric_Histogram{
				Histogram: &metricspb.Histogram{
					AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
					DataPoints: []*metricspb.HistogramDataPoint{
						{
							Count: 10,
							Sum:   &histSum,
						},
					},
				},
			},
		}

		histData, err := proto.Marshal(histMetric)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: proto.Marshal histMetric failed: %v\n", err)
			os.Exit(1)
		}

		var decodedHistMetric metricspb.Metric
		if err := proto.Unmarshal(histData, &decodedHistMetric); err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: proto.Unmarshal histMetric failed: %v\n", err)
			os.Exit(1)
		}

		if decodedHistMetric.GetHistogram().GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: decoded hist temporality mismatch: expected CUMULATIVE, got %s\n", decodedHistMetric.GetHistogram().GetAggregationTemporality())
			os.Exit(1)
		}
	}

	// Assertion 4: AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE serializes to JSON as enum string and enum number formats and round-trips correctly via protojson.
	{
		metric := &metricspb.Metric{
			Name: "requests_processed_total",
			Data: &metricspb.Metric_Sum{
				Sum: &metricspb.Sum{
					AggregationTemporality: metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE,
					IsMonotonic:            true,
				},
			},
		}

		// String format JSON
		jsonDefault, err := protojson.Marshal(metric)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: protojson.Marshal failed: %v\n", err)
			os.Exit(1)
		}
		if !strings.Contains(string(jsonDefault), `"AGGREGATION_TEMPORALITY_CUMULATIVE"`) {
			fmt.Fprintf(os.Stderr, "FAIL: expected string enum 'AGGREGATION_TEMPORALITY_CUMULATIVE' in JSON, got: %s\n", string(jsonDefault))
			os.Exit(1)
		}

		var roundTripDefault metricspb.Metric
		if err := protojson.Unmarshal(jsonDefault, &roundTripDefault); err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: protojson.Unmarshal default failed: %v\n", err)
			os.Exit(1)
		}
		if roundTripDefault.GetSum().GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: round-trip default temporality expected CUMULATIVE, got %v\n", roundTripDefault.GetSum().GetAggregationTemporality())
			os.Exit(1)
		}

		// Numeric format JSON
		optsNumeric := protojson.MarshalOptions{UseEnumNumbers: true}
		jsonNumeric, err := optsNumeric.Marshal(metric)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: protojson.Marshal with UseEnumNumbers failed: %v\n", err)
			os.Exit(1)
		}
		if !strings.Contains(string(jsonNumeric), `"aggregationTemporality":2`) && !strings.Contains(string(jsonNumeric), `"aggregation_temporality":2`) {
			fmt.Fprintf(os.Stderr, "FAIL: expected numeric enum 2 in JSON, got: %s\n", string(jsonNumeric))
			os.Exit(1)
		}

		var roundTripNumeric metricspb.Metric
		if err := protojson.Unmarshal(jsonNumeric, &roundTripNumeric); err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: protojson.Unmarshal numeric failed: %v\n", err)
			os.Exit(1)
		}
		if roundTripNumeric.GetSum().GetAggregationTemporality() != metricspb.AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE {
			fmt.Fprintf(os.Stderr, "FAIL: round-trip numeric temporality expected CUMULATIVE, got %v\n", roundTripNumeric.GetSum().GetAggregationTemporality())
			os.Exit(1)
		}
	}

	fmt.Println("PASS: all AggregationTemporality_AGGREGATION_TEMPORALITY_CUMULATIVE contract assertions passed")
}