workerlog

workerlog

Simple file-based logging for background workers with automatic rotation.

Features

• 📅 Date-based file naming: worker-YYYY-MM-DD.log
• 🔄 Automatic file rotation (oldest files deleted when limit exceeded)
• 🔒 Thread-safe operations
• 📖 Simple API for reading log files
• 📦 Zero external dependencies

Installation

go get github.com/alexeevp/workerlog

Usage

package main

import (
    "log"
    "github.com/alexeevp/workerlog"
)

func main() {
    // Create writer that keeps 7 days of logs
    writer := workerlog.NewWriter("var/logs/workers", 7)
    
    // Write log lines
    err := writer.Write("my-worker", []string{
        "Task started",
        "Processing item 1",
        "Task completed successfully",
    })
    if err != nil {
        log.Fatal(err)
    }
    
    // Get recent log files
    files := writer.GetLogFiles("my-worker", 3)
    for _, f := range files {
        log.Printf("Log file: %s (date: %s)", f.Filename, f.Date)
    }
    
    // Read specific log file
    content, err := writer.ReadLogFile("my-worker", "2026-02-19")
    if err != nil {
        log.Fatal(err)
    }
    log.Println(content)
}

API

Creating a Writer

writer := workerlog.NewWriter(baseDir string, maxFiles int)

• baseDir - Directory for log storage (e.g., "var/logs/workers")
• maxFiles - Maximum number of files per worker (oldest are deleted)

Writing Logs

err := writer.Write(workerName string, lines []string) error

Writes log lines to a file named {workerName}-{date}.log. Creates the file and directory if they don't exist.

Reading Log Files

// Get list of log files (newest first)
files := writer.GetLogFiles(workerName string, limit int) []FileInfo

// Read specific log file by date
content, err := writer.ReadLogFile(workerName string, date string) (string, error)

FileInfo

type FileInfo struct {
    Date     string // "2026-02-05"
    Filename string // "worker-2026-02-05.log"
}

File Format

Log files are named using the pattern {workerName}-{YYYY-MM-DD}.log:

• email-worker-2026-02-19.log
• cleanup-worker-2026-02-19.log
• report-worker-2026-02-18.log

Rotation

When the number of log files for a worker exceeds maxFiles, the oldest files are automatically deleted. Files are sorted by date in their filename.

License

MIT License - see LICENSE file