github.com/sirupsen/logrus v1.4.2: WarnLevel

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/sirupsen/logrus.WarnLevel in pkg:golang/github.com/sirupsen/logrus@v1.4.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/sirupsen/logrus@v1.4.2
Demonstrate these symbols/APIs:
  - github.com/sirupsen/logrus.WarnLevel

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:sha256:762d3cecc107daa3023538544d2b105b69735788613f8fd2891c5f1e157cd1f9","contract":["logrus.WarnLevel has string representation warning and is parsed from string by logrus.ParseLevel","Logger configured at logrus.WarnLevel enables WarnLevel and higher severity levels while filtering out InfoLevel, DebugLevel, and TraceLevel","Logger configured at logrus.WarnLevel emits Warn messages to destination writer and suppresses Info and Debug messages"],"goal":"verify github.com/sirupsen/logrus.WarnLevel in pkg:golang/github.com/sirupsen/logrus@v1.4.2","kind":"HOW","packages":["pkg:golang/github.com/sirupsen/logrus@v1.4.2"],"schemaVersion":1,"symbols":["github.com/sirupsen/logrus.WarnLevel"]},"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/sirupsen/logrus@v1.4.2"],"schemaVersion":1,"subject":"pkg:golang/github.com/sirupsen/logrus@v1.4.2","symbols":["github.com/sirupsen/logrus.WarnLevel"],"verifierAdapter":"golang@1"}

module sample

go 1.22

require github.com/sirupsen/logrus v1.4.2

require (
	github.com/konsorten/go-windows-terminal-sequences v1.0.1 // indirect
	golang.org/x/sys v0.0.0-20190422165155-953cdadca894 // indirect
)

github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
golang.org/x/sys v0.0.0-20190422165155-953cdadca894 h1:Cz4ceDQGXuKRnVBDTS23GTn/pU5OE2C0WrNTOYK1Uuc=
golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

{
  "schemaVersion": 1,
  "goal": "verify github.com/sirupsen/logrus.WarnLevel in pkg:golang/github.com/sirupsen/logrus@v1.4.2",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/sirupsen/logrus@v1.4.2"
  ],
  "symbols": [
    "github.com/sirupsen/logrus.WarnLevel"
  ]
}

package main

import (
	"encoding/json"
	"fmt"
	"os"

	"github.com/sirupsen/logrus"
	"sample"
)

type logEntry struct {
	Level string `json:"level"`
	Msg   string `json:"msg"`
}

func main() {
	fmt.Println("Running contract tests for github.com/sirupsen/logrus.WarnLevel...")

	// Assertion 1: logrus.WarnLevel has string representation warning and is parsed from string by logrus.ParseLevel
	{
		if sample.WarnLevelConstant() != logrus.WarnLevel {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: expected WarnLevel %v, got %v\n", logrus.WarnLevel, sample.WarnLevelConstant())
			os.Exit(1)
		}
		if sample.WarnLevelString() != "warning" {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: expected string 'warning', got %q\n", sample.WarnLevelString())
			os.Exit(1)
		}
		parsedWarn, err := sample.ParseWarnLevel("warn")
		if err != nil || parsedWarn != logrus.WarnLevel {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: ParseWarnLevel('warn') error: %v, got %v\n", err, parsedWarn)
			os.Exit(1)
		}
		parsedWarning, err := sample.ParseWarnLevel("warning")
		if err != nil || parsedWarning != logrus.WarnLevel {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: ParseWarnLevel('warning') error: %v, got %v\n", err, parsedWarning)
			os.Exit(1)
		}
		parsedUpper, err := sample.ParseWarnLevel("WARN")
		if err != nil || parsedUpper != logrus.WarnLevel {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: ParseWarnLevel('WARN') error: %v, got %v\n", err, parsedUpper)
			os.Exit(1)
		}
		fmt.Println("  ✓ Assertion 1 passed: logrus.WarnLevel string representation and parsing verified")
	}

	// Assertion 2: Logger configured at logrus.WarnLevel enables WarnLevel and higher severity levels while filtering out InfoLevel, DebugLevel, and TraceLevel
	{
		l := sample.NewWarnFilterLogger()
		if !l.IsEnabled(logrus.PanicLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: PanicLevel should be enabled\n")
			os.Exit(1)
		}
		if !l.IsEnabled(logrus.FatalLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: FatalLevel should be enabled\n")
			os.Exit(1)
		}
		if !l.IsEnabled(logrus.ErrorLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: ErrorLevel should be enabled\n")
			os.Exit(1)
		}
		if !l.IsEnabled(logrus.WarnLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: WarnLevel should be enabled\n")
			os.Exit(1)
		}
		if l.IsEnabled(logrus.InfoLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: InfoLevel should be disabled\n")
			os.Exit(1)
		}
		if l.IsEnabled(logrus.DebugLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: DebugLevel should be disabled\n")
			os.Exit(1)
		}
		if l.IsEnabled(logrus.TraceLevel) {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: TraceLevel should be disabled\n")
			os.Exit(1)
		}
		fmt.Println("  ✓ Assertion 2 passed: Level hierarchy enabling logic verified for WarnLevel")
	}

	// Assertion 3: Logger configured at logrus.WarnLevel emits Warn messages to destination writer and suppresses Info and Debug messages
	{
		l := sample.NewWarnFilterLogger()
		l.LogEvents("debug message should be suppressed", "info message should be suppressed", "warn message warning event")

		var entries []logEntry
		decoder := json.NewDecoder(l.Buffer)
		for decoder.More() {
			var entry logEntry
			if err := decoder.Decode(&entry); err != nil {
				fmt.Fprintf(os.Stderr, "Assertion 3 failed to decode log entry: %v\n", err)
				os.Exit(1)
			}
			entries = append(entries, entry)
		}

		if len(entries) != 1 {
			fmt.Fprintf(os.Stderr, "Assertion 3 failed: expected 1 entry, got %d (raw: %s)\n", len(entries), l.Buffer.String())
			os.Exit(1)
		}
		if entries[0].Level != "warning" || entries[0].Msg != "warn message warning event" {
			fmt.Fprintf(os.Stderr, "Assertion 3 failed: unexpected entry 0: %+v\n", entries[0])
			os.Exit(1)
		}
		fmt.Println("  ✓ Assertion 3 passed: WarnLevel emission and lower-level suppression verified")
	}

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

package sample

import (
	"bytes"

	"github.com/sirupsen/logrus"
)

// WarnLevelConstant returns the logrus.WarnLevel constant.
func WarnLevelConstant() logrus.Level {
	return logrus.WarnLevel
}

// WarnLevelString returns the string representation of logrus.WarnLevel.
func WarnLevelString() string {
	return logrus.WarnLevel.String()
}

// ParseWarnLevel parses a string into logrus.Level.
func ParseWarnLevel(s string) (logrus.Level, error) {
	return logrus.ParseLevel(s)
}

// WarnFilterLogger encapsulates a logrus.Logger configured at logrus.WarnLevel and an output buffer.
type WarnFilterLogger struct {
	Logger *logrus.Logger
	Buffer *bytes.Buffer
}

// NewWarnFilterLogger creates a logger set to WarnLevel writing to an internal buffer.
func NewWarnFilterLogger() *WarnFilterLogger {
	buf := &bytes.Buffer{}
	logger := logrus.New()
	logger.SetOutput(buf)
	logger.SetLevel(logrus.WarnLevel)
	logger.SetFormatter(&logrus.JSONFormatter{
		DisableTimestamp: true,
	})
	return &WarnFilterLogger{
		Logger: logger,
		Buffer: buf,
	}
}

// IsEnabled checks if the given level is enabled on the logger.
func (l *WarnFilterLogger) IsEnabled(level logrus.Level) bool {
	return l.Logger.IsLevelEnabled(level)
}

// LogEvents logs debug, info, and warn messages to demonstrate level filtering.
func (l *WarnFilterLogger) LogEvents(debugMsg, infoMsg, warnMsg string) {
	l.Logger.Debug(debugMsg)
	l.Logger.Info(infoMsg)
	l.Logger.Warn(warnMsg)
}