Logging

// Package logging builds a single, structured zerolog.Logger every service
// in this platform uses. It knows two environments: a colorized console
// writer for a developer's terminal, raw JSON for anywhere logs are
// collected and parsed by machines.
package logging

import (
	"io"
	"os"

	"github.com/rs/zerolog"
)

// New returns a logger tagged with the given service name. env selects the
// output format: "production" and "staging" write raw JSON straight to
// stdout; anything else (including an empty string) is wrapped in
// zerolog.ConsoleWriter for human-readable output, matching this service's
// own ORGANIZATION_ENV default of "development". zerolog.Logger is a small
// value type — every function in this platform accepts and stores it by
// value, never by pointer.
func New(service, env, level string) zerolog.Logger {
	var writer io.Writer = os.Stdout
	if env != "production" && env != "staging" {
		writer = zerolog.ConsoleWriter{Out: os.Stdout}
	}

	return zerolog.New(writer).
		Level(parseLevel(level)).
		With().
		Timestamp().
		Str("service", service).
		Str("env", env).
		Logger()
}

// parseLevel falls back to Info for anything it does not recognize, rather
// than failing service startup over a log-level typo.
func parseLevel(level string) zerolog.Level {
	switch level {
	case "debug":
		return zerolog.DebugLevel
	case "warn":
		return zerolog.WarnLevel
	case "error":
		return zerolog.ErrorLevel
	default:
		return zerolog.InfoLevel
	}
}

 type Config struct {
    Env      string `env:"ORGANIZATION_ENV" env-default:"development"`
    Port     int    `env:"ORGANIZATION_PORT" env-default:"8080"`
+	LogLevel string `env:"ORGANIZATION_LOG_LEVEL" env-default:"info"`
 }

# ORGANIZATION_ENV=development
2024-01-01T09:00:00+00:00 INF listening addr=:8080 env=development service=organization

# ORGANIZATION_ENV=production
{"level":"info","service":"organization","env":"production","time":"2024-01-01T09:00:00Z","addr":":8080","message":"listening"}