github.com/sirupsen/logrus v1.10.2

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/sirupsen/logrus@v1.10.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/sirupsen/logrus@v1.10.2

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.

{"case":{"caseId":"case:sha256:17ce4a6f24c5d543fc7ac6e947c515e029efd06ba5d3a3f5154c0b89b1cf0f61","contract":["logrus.New creates a Logger with default InfoLevel and TextFormatter","Logger.SetLevel filters messages logged below the configured Level","Logger.WithFields attaches structured key-value pairs to subsequent log entries without mutating parent fields","Logger.SetFormatter with JSONFormatter formats log output into valid JSON containing level, msg, and fields","Entry.WithError attaches error object under the ErrorKey field"],"goal":"verify pkg:golang/github.com/sirupsen/logrus@v1.10.2","kind":"HOW","packages":["pkg:golang/github.com/sirupsen/logrus@v1.10.2"],"schemaVersion":1},"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@v1.10.2"],"schemaVersion":1,"subject":"pkg:golang/github.com/sirupsen/logrus@v1.10.2","verifierAdapter":"golang@1"}

module sample

go 1.23

require github.com/sirupsen/logrus v1.10.2

require golang.org/x/sys v0.13.0 // indirect

github.com/sirupsen/logrus v1.10.2 h1:G2SED73/qrAu6YwbdxOD6peLkCBI3z7L+ykJFTXJBBo=
github.com/sirupsen/logrus v1.10.2/go.mod h1:SLEg8TqYulVKKfIGHldVp2K2aYz2DKSVBq4g/H5bR7Q=
github.com/stretchr/testify v1.12.1 h1:EuwCh5fleGS7H32xRwO3wRGT7DxrDhLAT6FF8MpWDWE=
github.com/stretchr/testify v1.12.1/go.mod h1:MDEgiDPPsNp5cuIrHPPCyornHKgEVbtFUmoNlxoYthg=
go.yaml.in/yaml/v3 v3.0.5 h1:N6y/pJk8buWs9NY5ERU2HSMfm+IuD/OtfdAnq6kESPw=
go.yaml.in/yaml/v3 v3.0.5/go.mod h1:HVTZu1O7/Vkt2N+BFy8Zza+lnLsABggaTM2ZpNIGuKg=
golang.org/x/sys v0.13.0 h1:Af8nKPmuFypiUBjVoU9V20FiaFXOcuZI21p0ycVYYGE=
golang.org/x/sys v0.13.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

package main

import (
	"bytes"
	"fmt"

	"github.com/sirupsen/logrus"
)

func main() {
	buf := new(bytes.Buffer)
	logger := logrus.New()
	logger.SetOutput(buf)
	logger.SetFormatter(&logrus.TextFormatter{
		DisableColors: true,
	})

	logger.WithField("app", "sample").Info("logrus initialized")
	fmt.Print(buf.String())
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/sirupsen/logrus@v1.10.2",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/sirupsen/logrus@v1.10.2"
  ]
}

package main

import (
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"os"
	"strings"

	"github.com/sirupsen/logrus"
)

func main() {
	if err := runContract(); err != nil {
		fmt.Fprintf(os.Stderr, "Contract verification failed: %v\n", err)
		os.Exit(1)
	}
	fmt.Println("All logrus contract assertions passed successfully.")
}

func runContract() error {
	// Assertion 1: logrus.New creates a Logger with default InfoLevel and TextFormatter
	logger := logrus.New()
	if logger.GetLevel() != logrus.InfoLevel {
		return fmt.Errorf("expected default level to be InfoLevel, got %v", logger.GetLevel())
	}
	if logger.Formatter == nil {
		return fmt.Errorf("expected logger.Formatter to be non-nil")
	}

	// Assertion 2: Logger.SetLevel filters messages logged below the configured Level
	buf := new(bytes.Buffer)
	filterLogger := logrus.New()
	filterLogger.SetOutput(buf)
	filterLogger.SetLevel(logrus.WarnLevel)
	filterLogger.Info("this should be filtered out")
	if buf.Len() != 0 {
		return fmt.Errorf("expected Info message to be filtered out at WarnLevel, got %q", buf.String())
	}
	filterLogger.Warn("this should be logged")
	if !strings.Contains(buf.String(), "this should be logged") {
		return fmt.Errorf("expected Warn message to be logged, got %q", buf.String())
	}

	// Assertion 3: Logger.WithFields attaches structured key-value pairs to subsequent log entries without mutating parent fields
	parentEntry := logrus.NewEntry(logger)
	childEntry := parentEntry.WithFields(logrus.Fields{
		"service":  "auth",
		"attempts": 2,
	})
	if childEntry.Data["service"] != "auth" || childEntry.Data["attempts"] != 2 {
		return fmt.Errorf("expected childEntry to have fields, got %v", childEntry.Data)
	}
	if _, exists := parentEntry.Data["service"]; exists {
		return fmt.Errorf("expected parentEntry to remain unchanged")
	}

	// Assertion 4: Logger.SetFormatter with JSONFormatter formats log output into valid JSON containing level, msg, and fields
	jsonBuf := new(bytes.Buffer)
	jsonLogger := logrus.New()
	jsonLogger.SetOutput(jsonBuf)
	jsonLogger.SetFormatter(&logrus.JSONFormatter{})
	jsonLogger.WithField("user_id", 42).Info("user logged in")

	var parsed map[string]interface{}
	if err := json.Unmarshal(jsonBuf.Bytes(), &parsed); err != nil {
		return fmt.Errorf("failed to parse JSONFormatter output as JSON: %w", err)
	}
	if parsed["msg"] != "user logged in" {
		return fmt.Errorf("expected msg 'user logged in', got %v", parsed["msg"])
	}
	if parsed["level"] != "info" {
		return fmt.Errorf("expected level 'info', got %v", parsed["level"])
	}
	if parsed["user_id"] != float64(42) {
		return fmt.Errorf("expected user_id 42, got %v", parsed["user_id"])
	}

	// Assertion 5: Entry.WithError attaches error object under the ErrorKey field
	testErr := errors.New("connection failed")
	errEntry := logrus.NewEntry(logger).WithError(testErr)
	if errEntry.Data[logrus.ErrorKey] != testErr {
		return fmt.Errorf("expected error at ErrorKey %q, got %v", logrus.ErrorKey, errEntry.Data[logrus.ErrorKey])
	}

	return nil
}