github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432: graphite.Config, graphite.Once

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 pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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.

package sample

import (
	"bufio"
	"net"
	"strings"
	"sync"
	"testing"
	"time"

	"github.com/rcrowley/go-metrics"
)

func TestContract(t *testing.T) {
	// 1. Verify graphite.Config defines exporter settings
	registry := metrics.NewRegistry()
	dummyAddr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("failed to resolve dummy TCP addr: %v", err)
	}

	cfg := NewConfig(dummyAddr, registry, "csx.app", 5*time.Second)
	if cfg.Prefix != "csx.app" {
		t.Fatalf("expected Prefix 'csx.app', got %q", cfg.Prefix)
	}
	if cfg.Registry != registry {
		t.Fatalf("expected Registry to match")
	}
	if cfg.FlushInterval != 5*time.Second {
		t.Fatalf("expected FlushInterval 5s, got %v", cfg.FlushInterval)
	}

	// 2. Verify graphite.Once flushes Counter and Gauge metrics to a Graphite TCP server
	ln, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("failed to start mock Graphite TCP listener: %v", err)
	}
	defer ln.Close()

	serverAddr := ln.Addr().(*net.TCPAddr)

	receivedLines := make([]string, 0)
	var wg sync.WaitGroup
	wg.Add(1)

	go func() {
		defer wg.Done()
		conn, err := ln.Accept()
		if err != nil {
			return
		}
		defer conn.Close()

		scanner := bufio.NewScanner(conn)
		for scanner.Scan() {
			receivedLines = append(receivedLines, scanner.Text())
		}
	}()

	counter := metrics.GetOrRegisterCounter("requests.total", registry)
	counter.Inc(42)

	gauge := metrics.GetOrRegisterGauge("active.workers", registry)
	gauge.Update(10)

	serverCfg := NewConfig(serverAddr, registry, "csx.metrics", 1*time.Second)
	if err := FlushOnce(serverCfg); err != nil {
		t.Fatalf("FlushOnce failed: %v", err)
	}

	wg.Wait()

	if len(receivedLines) == 0 {
		t.Fatalf("expected metric lines to be received, got none")
	}

	var foundCounter, foundGauge bool
	for _, l := range receivedLines {
		if strings.HasPrefix(l, "csx.metrics.requests.total.count 42 ") {
			foundCounter = true
		}
		if strings.HasPrefix(l, "csx.metrics.active.workers.value 10 ") {
			foundGauge = true
		}
	}

	if !foundCounter {
		t.Fatalf("expected counter metric line 'csx.metrics.requests.total.count 42 <ts>', received lines: %v", receivedLines)
	}
	if !foundGauge {
		t.Fatalf("expected gauge metric line 'csx.metrics.active.workers.value 10 <ts>', received lines: %v", receivedLines)
	}

	// 3. Verify graphite.Once returns an error when the TCP address is unreachable
	closedLn, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("failed to listen temporarily: %v", err)
	}
	closedAddr := closedLn.Addr().(*net.TCPAddr)
	closedLn.Close() // immediately close to make port unreachable

	unreachableCfg := NewConfig(closedAddr, registry, "csx.metrics", 1*time.Second)
	if err := FlushOnce(unreachableCfg); err == nil {
		t.Fatalf("expected FlushOnce to return error for unreachable address, got nil")
	}
}

{"case":{"caseId":"case:sha256:fdb59031dcd9e75c48471c03338ef118556215d2e6a130c337a7c2b465d7858a","contract":["graphite.Config defines exporter settings with Addr, Registry, and Prefix","graphite.Once flushes Counter and Gauge metrics to a Graphite TCP server","graphite.Once returns an error when the TCP address is unreachable"],"goal":"verify pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432","kind":"HOW","packages":["pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432"],"schemaVersion":1,"symbols":["graphite.Config","graphite.Once"]},"contractCommand":["go","test","./..."],"environment":{"arch":"amd64","compiler":"go","compilerVersion":"1.26.6","distro":"ubuntu","ecosystem":"golang","language":"go","languageVersion":"1.26.6","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","packageManagerVersion":"1.26.6","runtime":"go","runtimeVersion":"1.26.6","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432"],"schemaVersion":1,"subject":"pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432","symbols":["graphite.Config","graphite.Once"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.26.6

require (
	github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432
	github.com/rcrowley/go-metrics v0.0.0-20250401214520-65e299d6c5c9
)

github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432 h1:M5QgkYacWj0Xs8MhpIK/5uwU02icXpEoSo9sM2aRCps=
github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432/go.mod h1:xwIwAxMvYnVrGJPe2FKx5prTrnAjGOD8zvDOnxnrrkM=
github.com/rcrowley/go-metrics v0.0.0-20250401214520-65e299d6c5c9 h1:bsUq1dX0N8AOIL7EB/X911+m4EHsnWEHeJ0c+3TTBrg=
github.com/rcrowley/go-metrics v0.0.0-20250401214520-65e299d6c5c9/go.mod h1:bCqnVzQkZxMG4s8nGwiZ5l3QUCyqpo9Y+/ZMZ9VjZe4=

package sample

import (
	"net"
	"time"

	graphite "github.com/cyberdelia/go-metrics-graphite"
	"github.com/rcrowley/go-metrics"
)

// NewConfig creates a new Graphite exporter Config.
func NewConfig(addr *net.TCPAddr, registry metrics.Registry, prefix string, flushInterval time.Duration) graphite.Config {
	return graphite.Config{
		Addr:          addr,
		Registry:      registry,
		FlushInterval: flushInterval,
		DurationUnit:  time.Millisecond,
		Prefix:        prefix,
		Percentiles:   []float64{0.5, 0.75, 0.95, 0.99},
	}
}

// FlushOnce performs a single metrics flush to Graphite.
func FlushOnce(cfg graphite.Config) error {
	return graphite.Once(cfg)
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/cyberdelia/go-metrics-graphite@v0.0.0-20161219230853-39f87cc3b432"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}