coco-logger

coco-logger

A lightweight file logger for Go with daily folder structure and simple API.

Features

• Writes to log files with automatic, date-based folder structure (YYYY/MM/DD)
• Thread-safe logging (mutex-protected)
• Simple methods: Info, Warning, Error, Close
• Configurable log directory path

Installation

Use Go Modules and add the module to your project. Adjust the module path to your actual repository.

go get github.com/your-org/coco-logger

Import the logger from the src/logger package:

import logger "github.com/your-org/coco-logger/src/logger"

Quick Start

package main

import (
    logger "github.com/your-org/coco-logger/src/logger"
)

func main() {
    // Set your log directory (structured by date)
    log, err := logger.NewLogger("app.log", "./logs")
    if err != nil {
        panic(err)
    }
    defer log.Close()

    log.Info("service starting: version %s", "0.1.0")
    log.Warning("slower than expected: duration_ms=%d", 120)
    log.Error("failed to do work: err=%s", "some error")
}

Logs are written to a path like ./logs/2026/02/14/app.log.

API

• NewLogger(fileName string, logDir string) (Logger, error)
  • Creates a new logger that writes to logDir/YYYY/MM/DD/fileName
  • logDir must be set (no fallback)
• Info(msg string, args ...interface{})
• Warning(msg string, args ...interface{})
• Error(msg string, args ...interface{})
• Close() closes the file resource

Format

Each log entry is written as a simple text line:

[YYYY-MM-DD HH:MM:SS] [LEVEL] message\n

Example:

[2026-02-14 10:23:45] [INFO] service starting: version 0.1.0

Best Practices

• Always call Close() (e.g., with defer) to close file handles
• Choose a meaningful logDir (e.g., ./logs or /var/log/myapp)
• Output structured information as part of the message (key=value), e.g., duration_ms=120
• Avoid logging sensitive data (PII/secrets)

Tests

To run all unit and integration tests, use:

go test ./tests/unit/... ./tests/integration/... -v

If you want to run all tests recursively:

go test ./tests/... -v

Versioning

This project follows semantic versioning; breaking changes may occur until v1.0.

License

This project is released under the MIT license. See LICENSE.