github.com/rs/zerolog v1.15.0: ErrorLevel

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/rs/zerolog.ErrorLevel in pkg:golang/github.com/rs/zerolog@v1.15.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/rs/zerolog@v1.15.0
Demonstrate these symbols/APIs:
  - github.com/rs/zerolog.ErrorLevel

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:bb84c8178aa869219703dc21e671e9421e78aa850859301b79cefe41f67baae2","contract":["zerolog.ErrorLevel has string representation \"error\"","zerolog.ParseLevel parses string \"error\" to zerolog.ErrorLevel","zerolog.Logger configured with ErrorLevel emits error log messages with level \"error\"","zerolog.Logger configured with ErrorLevel suppresses debug, info, and warn log messages","zerolog.SetGlobalLevel set to ErrorLevel filters out messages below ErrorLevel globally"],"goal":"verify github.com/rs/zerolog.ErrorLevel in pkg:golang/github.com/rs/zerolog@v1.15.0","kind":"HOW","packages":["pkg:golang/github.com/rs/zerolog@v1.15.0"],"schemaVersion":1,"symbols":["github.com/rs/zerolog.ErrorLevel"]},"contractCommand":["go","run","./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/rs/zerolog@v1.15.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/rs/zerolog@v1.15.0","symbols":["github.com/rs/zerolog.ErrorLevel"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/rs/zerolog v1.15.0

github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
github.com/rs/zerolog v1.15.0 h1:uPRuwkWF4J6fGsJ2R0Gn2jB1EQiav9k3S6CSdygQJXY=
github.com/rs/zerolog v1.15.0/go.mod h1:xYTKnLHcpfU2225ny5qZjxnj9NvkumZYjJHlAThCjNc=
github.com/zenazn/goji v0.9.0/go.mod h1:7S9M489iMyHBNxwZnk9/EHS098H4/F6TATF2mIxtB1Q=
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/tools v0.0.0-20190425163242-31fd60d6bfdc/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=

package main

import (
	"bytes"
	"fmt"

	"github.com/rs/zerolog"
)

func main() {
	buf := &bytes.Buffer{}
	logger := zerolog.New(buf).Level(zerolog.ErrorLevel)

	// Demonstrating ErrorLevel usage
	fmt.Printf("Level name: %s\n", zerolog.ErrorLevel.String())

	// Lower level events (e.g. info, warn) are discarded
	logger.Info().Msg("this info message is ignored")
	logger.Warn().Msg("this warn message is ignored")

	// Error level events are recorded
	logger.Error().Str("component", "database").Msg("database connection failed")

	fmt.Printf("Log output: %s", buf.String())
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/rs/zerolog.ErrorLevel in pkg:golang/github.com/rs/zerolog@v1.15.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/rs/zerolog@v1.15.0"
  ],
  "symbols": [
    "github.com/rs/zerolog.ErrorLevel"
  ]
}

package main

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

	"github.com/rs/zerolog"
)

func main() {
	// Assertion 1: zerolog.ErrorLevel has string representation "error"
	{
		if zerolog.ErrorLevel.String() != "error" {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: expected 'error', got %q\n", zerolog.ErrorLevel.String())
			os.Exit(1)
		}
	}

	// Assertion 2: zerolog.ParseLevel parses string "error" to zerolog.ErrorLevel
	{
		parsed, err := zerolog.ParseLevel("error")
		if err != nil {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: ParseLevel('error') returned error: %v\n", err)
			os.Exit(1)
		}
		if parsed != zerolog.ErrorLevel {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: expected ErrorLevel (%v), got %v\n", zerolog.ErrorLevel, parsed)
			os.Exit(1)
		}
	}

	// Assertion 3: zerolog.Logger configured with ErrorLevel emits error log messages with level "error"
	{
		buf := &bytes.Buffer{}
		logger := zerolog.New(buf).Level(zerolog.ErrorLevel)
		logger.Error().Str("operation", "query").Msg("connection refused")

		var parsed map[string]interface{}
		if err := json.Unmarshal(buf.Bytes(), &parsed); err != nil {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: invalid JSON output: %v\n", err)
			os.Exit(1)
		}
		if parsed["level"] != "error" {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: expected level 'error', got %v\n", parsed["level"])
			os.Exit(1)
		}
		if parsed["operation"] != "query" || parsed["message"] != "connection refused" {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: fields mismatch: %+v\n", parsed)
			os.Exit(1)
		}
	}

	// Assertion 4: zerolog.Logger configured with ErrorLevel suppresses debug, info, and warn log messages
	{
		buf := &bytes.Buffer{}
		logger := zerolog.New(buf).Level(zerolog.ErrorLevel)
		logger.Debug().Msg("debug event suppressed")
		logger.Info().Msg("info event suppressed")
		logger.Warn().Msg("warn event suppressed")

		if buf.Len() != 0 {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: expected suppressed events, got: %s\n", buf.String())
			os.Exit(1)
		}
	}

	// Assertion 5: zerolog.SetGlobalLevel set to ErrorLevel filters out messages below ErrorLevel globally
	{
		prevLevel := zerolog.GlobalLevel()
		defer zerolog.SetGlobalLevel(prevLevel)

		zerolog.SetGlobalLevel(zerolog.ErrorLevel)
		buf := &bytes.Buffer{}
		logger := zerolog.New(buf)

		logger.Warn().Msg("warn message suppressed by global level")
		if buf.Len() != 0 {
			fmt.Fprintf(os.Stderr, "assertion 5 failed: expected global suppression of warn level, got: %s\n", buf.String())
			os.Exit(1)
		}

		logger.Error().Msg("error message allowed by global level")
		if buf.Len() == 0 {
			fmt.Fprintf(os.Stderr, "assertion 5 failed: expected error message to be recorded\n")
			os.Exit(1)
		}
	}

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