github.com/prometheus/client_model v0.6.1: go.Untyped

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 github.com/prometheus/client_model/go.Untyped in pkg:golang/github.com/prometheus/client_model@v0.6.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/prometheus/client_model@v0.6.1
Demonstrate these symbols/APIs:
  - github.com/prometheus/client_model/go.Untyped

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:sha256:245dc2c855e144415aeaa88d0cabe4c0d7b1ea0e573ce6c11c102dfa316da2b5","contract":["Untyped creates an instance with a float64 pointer value and GetValue returns the assigned value","Untyped GetValue safely returns zero when Value pointer or receiver is nil","Untyped Reset clears the metric value to nil","Metric encapsulates Untyped metric and GetUntyped returns the instance","MetricFamily groups Untyped metrics under MetricType_UNTYPED"],"goal":"verify github.com/prometheus/client_model/go.Untyped in pkg:golang/github.com/prometheus/client_model@v0.6.1","kind":"HOW","packages":["pkg:golang/github.com/prometheus/client_model@v0.6.1"],"schemaVersion":1,"symbols":["github.com/prometheus/client_model/go.Untyped"]},"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/github.com/prometheus/client_model@v0.6.1"],"schemaVersion":1,"subject":"pkg:golang/github.com/prometheus/client_model@v0.6.1","symbols":["github.com/prometheus/client_model/go.Untyped"],"verifierAdapter":"golang@1"}

module example.com/contract

go 1.26.6

require github.com/prometheus/client_model v0.6.1

require google.golang.org/protobuf v1.33.0 // indirect

github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
github.com/prometheus/client_model v0.6.1 h1:ZKSh/rekM+n3CeS952MLRAdFwIKqeY8b62p8ais2e9E=
github.com/prometheus/client_model v0.6.1/go.mod h1:OrxVMOVHjw3lKMa8+x6HeMGkHMQyHDk9E3jmP2AmGiY=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=

package main

import (
	"fmt"

	dto "github.com/prometheus/client_model/go"
)

func main() {
	val := 42.0
	untypedMetric := &dto.Untyped{
		Value: &val,
	}

	fmt.Printf("Untyped metric value: %f\n", untypedMetric.GetValue())

	metricName := "example_untyped_metric"
	metricHelp := "An example Prometheus untyped metric"
	metricType := dto.MetricType_UNTYPED

	metric := &dto.Metric{
		Untyped: untypedMetric,
	}

	mf := &dto.MetricFamily{
		Name:   &metricName,
		Help:   &metricHelp,
		Type:   &metricType,
		Metric: []*dto.Metric{metric},
	}

	fmt.Printf("Metric family: %s (type=%s, count=%d)\n",
		mf.GetName(), mf.GetType().String(), len(mf.GetMetric()))
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/prometheus/client_model/go.Untyped in pkg:golang/github.com/prometheus/client_model@v0.6.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/prometheus/client_model@v0.6.1"
  ],
  "symbols": [
    "github.com/prometheus/client_model/go.Untyped"
  ]
}

package main

import (
	"fmt"
	"os"

	dto "github.com/prometheus/client_model/go"
)

func main() {
	// Assertion 1: assert Untyped creates an instance with a float64 pointer value and GetValue returns the assigned value
	val := 42.5
	u := &dto.Untyped{
		Value: &val,
	}
	if u == nil {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: Untyped instance is nil\n")
		os.Exit(1)
	}
	if u.Value == nil || *u.Value != 42.5 {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: u.Value mismatch: got %v, expected 42.5\n", u.Value)
		os.Exit(1)
	}
	if u.GetValue() != 42.5 {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: u.GetValue() mismatch: got %f, expected 42.5\n", u.GetValue())
		os.Exit(1)
	}

	// Assertion 2: assert Untyped GetValue safely returns 0 when Value pointer or receiver is nil
	var nilUntyped *dto.Untyped
	if nilUntyped.GetValue() != 0.0 {
		fmt.Fprintf(os.Stderr, "assertion 2 failed: nilUntyped.GetValue() expected 0.0, got %f\n", nilUntyped.GetValue())
		os.Exit(1)
	}
	emptyUntyped := &dto.Untyped{}
	if emptyUntyped.GetValue() != 0.0 {
		fmt.Fprintf(os.Stderr, "assertion 2 failed: emptyUntyped.GetValue() expected 0.0, got %f\n", emptyUntyped.GetValue())
		os.Exit(1)
	}

	// Assertion 3: assert Untyped Reset clears the metric value to nil
	uReset := &dto.Untyped{
		Value: &val,
	}
	uReset.Reset()
	if uReset.Value != nil {
		fmt.Fprintf(os.Stderr, "assertion 3 failed: uReset.Value expected nil after Reset, got %v\n", uReset.Value)
		os.Exit(1)
	}
	if uReset.GetValue() != 0.0 {
		fmt.Fprintf(os.Stderr, "assertion 3 failed: uReset.GetValue() expected 0.0 after Reset, got %f\n", uReset.GetValue())
		os.Exit(1)
	}

	// Assertion 4: assert Metric encapsulates Untyped metric and GetUntyped returns the instance
	m := &dto.Metric{
		Untyped: u,
	}
	if m.GetUntyped() == nil {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: m.GetUntyped() returned nil\n")
		os.Exit(1)
	}
	if m.GetUntyped().GetValue() != 42.5 {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: m.GetUntyped().GetValue() expected 42.5, got %f\n", m.GetUntyped().GetValue())
		os.Exit(1)
	}
	if m.GetCounter() != nil || m.GetGauge() != nil {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: counter or gauge should be nil on untyped metric\n")
		os.Exit(1)
	}

	// Assertion 5: assert MetricFamily groups Untyped metrics under MetricType_UNTYPED
	metricName := "http_request_duration_untyped"
	metricHelp := "Untyped distribution or summary metric"
	metricType := dto.MetricType_UNTYPED
	labelKey := "endpoint"
	labelVal := "/api/v1/resource"
	m.Label = []*dto.LabelPair{
		{
			Name:  &labelKey,
			Value: &labelVal,
		},
	}

	mf := &dto.MetricFamily{
		Name:   &metricName,
		Help:   &metricHelp,
		Type:   &metricType,
		Metric: []*dto.Metric{m},
	}

	if mf.GetName() != metricName {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: mf.GetName() expected %q, got %q\n", metricName, mf.GetName())
		os.Exit(1)
	}
	if mf.GetType() != dto.MetricType_UNTYPED {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: mf.GetType() expected UNTYPED, got %v\n", mf.GetType())
		os.Exit(1)
	}
	if len(mf.GetMetric()) != 1 {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: len(mf.GetMetric()) expected 1, got %d\n", len(mf.GetMetric()))
		os.Exit(1)
	}
	if mf.GetMetric()[0].GetUntyped().GetValue() != 42.5 {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: mf metric untyped value expected 42.5, got %f\n", mf.GetMetric()[0].GetUntyped().GetValue())
		os.Exit(1)
	}

	fmt.Println("All contract assertions passed.")
}