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An advanced logging and metrics management tool with native support for Prometheus integration, dynamic notifications, and a powerful CLI.

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Table of Contents

1. About the Project
2. Features
3. Installation
4. Usage
   • Basic Logging Examples
   • Advanced Features
   • Production Usage Examples
   • Command Line Interface
   • Configuration
5. Performance and Benchmarks
6. Prometheus Integration
7. Roadmap
8. Contributing
9. Contact

---

About the Project

Logz is a flexible and powerful solution for managing logs and metrics in modern systems. Built in Go, it provides extensive support for multiple notification methods such as HTTP Webhooks, WebSocket real-time streaming, and native Prometheus integration, alongside seamless integration with monitoring systems for advanced observability.

Logz is designed to be robust, highly configurable, and scalable, catering to developers, DevOps teams, and software architects who need a centralized approach to logging, metrics and many other aspects of their systems.

What makes Logz special?

• 🚀 Production Tested: Successfully handles 500+ concurrent logging operations
• 🌊 Real-time Streaming: WebSocket support for live log monitoring
• 📊 Native Prometheus: Built-in metrics collection and HTTP endpoint exposure
• 🎯 Zero Mocking: All tests use real HTTP servers and WebSocket connections
• 🧪 Comprehensive Testing: 11+ integration tests covering all features
• 🔗 Easy Integration: Simple API that works with existing Go applications

Why Logz?

• 💡 Ease of Use: Configure and manage logs effortlessly with intuitive APIs
• 🌐 Seamless Integration: Drop-in replacement for standard logging with advanced features
• 🔧 Extensibility: Add new notifiers and services as needed
• 🏭 Enterprise Ready: Thread-safe, high-performance logging for production workloads

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Features

✨ Advanced Logging System:

• Multiple Log Levels: DEBUG, INFO, WARN, ERROR with beautiful emoji formatting
• Thread-Safe Concurrent Logging: Handle thousands of simultaneous log operations
• LogEntry Builder Pattern: Flexible and intuitive log entry construction
• Multiple Formatters: JSON structured logs and colorful text output

🌐 Real-Time Notifications:

• HTTP Webhooks: Send logs to external services via HTTP POST
• WebSocket Integration: Real-time log streaming to connected clients
• Dynamic Notifier Management: Add/remove notifiers on the fly
• Authentication Support: Secure webhook delivery with token-based auth

📊 Prometheus Integration:

• Native Metrics Support: Counter, Gauge, and custom metric types
• HTTP Metrics Endpoint: Standard /metrics endpoint for Prometheus scraping
• Metric Persistence: Automatic saving/loading of metrics to/from disk
• Metric Validation: Enforces Prometheus naming conventions
• Whitelist Support: Control which metrics are exported

🔧 Developer Experience:

• Zero Mocking Required: All tests use real HTTP servers and WebSocket connections
• Comprehensive Test Suite: 11+ integration tests covering all features
• Simple API: Easy-to-use interfaces for quick integration
• Context-Aware Logging: Rich metadata support for better debugging

🚀 Production Ready:

• High Performance: Tested with 500+ concurrent operations
• Memory Efficient: Optimized mutex usage and resource management
• Error Handling: Robust error handling and recovery mechanisms
• Configurable: Flexible configuration options for different environments

---

Installation

Requirements:

• Go version 1.19 or later.
• Prometheus (optional for advanced monitoring).

# Clone this repository
git clone https://github.com/rafa-mori/logz.git

# Navigate to the project directory
cd logz

# Build the binary using make
make build

# Install the binary using make
make install

# (Optional) Add the binary to the PATH to use it globally
export PATH=$PATH:$(pwd)

---

Usage

Basic Logging Examples

Simple Logging

package main

import "github.com/rafa-mori/logz/logger"

func main() {
    // Create a new logger instance
    log := logger.NewLogger("my-app")

    // Basic logging with emoji formatting
    log.InfoCtx("Application started successfully", nil)
    log.WarnCtx("This is a warning message", nil)
    log.ErrorCtx("Something went wrong", nil)
}

Output:

 [INFO]  ℹ️  - Application started successfully
 [WARN]  ⚠️  - This is a warning message
 [ERROR] ❌  - Something went wrong

Logging with Metadata

package main

import "github.com/rafa-mori/logz/logger"

func main() {
    log := logger.NewLogger("my-service")

    // Set global metadata
    log.SetMetadata("service", "user-api")
    log.SetMetadata("version", "1.2.3")

    // Log with additional context
    log.InfoCtx("User login successful", map[string]interface{}{
        "user_id":    12345,
        "ip_address": "192.168.1.100",
        "duration":   "250ms",
    })
}

Using LogEntry Builder Pattern

package main

import (
    "fmt"
    "github.com/rafa-mori/logz/internal/core"
)

func main() {
    // Create structured log entries
    entry := core.NewLogEntry().
        WithLevel(core.INFO).
        WithMessage("Payment processed successfully").
        AddMetadata("transaction_id", "txn_123456").
        AddMetadata("amount", 99.99).
        AddMetadata("currency", "USD").
        SetSeverity(1)

    // Use the entry with formatters
    formatter := core.NewJSONFormatter()
    output := formatter.Format(entry)
    fmt.Println(output)
}

Advanced Features

HTTP Webhook Notifications

package main

import (
    "github.com/rafa-mori/logz/logger"
    "github.com/rafa-mori/logz/internal/core"
)

func main() {
    // Create logger with HTTP notifier
    log := logger.NewLogger("webhook-app")

    // Add HTTP webhook notifier
    httpNotifier := core.NewHTTPNotifier(
        "https://hooks.slack.com/services/YOUR/WEBHOOK/URL",
        "your-auth-token",
    )

    // Create log entry
    entry := core.NewLogEntry().
        WithLevel(core.ERROR).
        WithMessage("Critical system error detected").
        AddMetadata("severity", "high").
        AddMetadata("component", "database")

    // Send notification
    err := httpNotifier.Notify(entry)
    if err != nil {
        log.ErrorCtx("Failed to send webhook", map[string]interface{}{
            "error": err.Error(),
        })
    }
}

WebSocket Real-Time Logging

package main

import (
    "fmt"
    "time"
    "github.com/rafa-mori/logz/internal/core"
)

func main() {
    // Create WebSocket notifier
    wsNotifier := core.NewWebSocketNotifier("ws://localhost:8080/logs", nil)

    // Create and send log entry
    entry := core.NewLogEntry().
        WithLevel(core.INFO).
        WithMessage("Real-time log update").
        AddMetadata("timestamp", time.Now().Unix()).
        AddMetadata("event", "user_action")

    err := wsNotifier.Notify(entry)
    if err != nil {
        fmt.Printf("WebSocket notification failed: %v\n", err)
    }
}

Prometheus Metrics Integration

package main

import "github.com/rafa-mori/logz/internal/core"

func main() {
    // Get Prometheus manager instance
    prometheus := core.GetPrometheusManager()

    // Add various metrics
    prometheus.AddMetric("http_requests_total", 100, map[string]string{
        "method": "GET",
        "status": "200",
    })

    prometheus.AddMetric("response_time_seconds", 0.045, map[string]string{
        "endpoint": "/api/users",
    })

    // Increment counter
    prometheus.IncrementMetric("api_calls_total", 1)

    // Start HTTP server to expose /metrics endpoint
    prometheus.StartHTTPServer(":2112")
}

Concurrent Logging (Production Ready)

package main

import (
    "sync"
    "github.com/rafa-mori/logz/logger"
)

func main() {
    log := logger.NewLogger("concurrent-app")
    var wg sync.WaitGroup

    // Simulate high-traffic logging
    for i := 0; i < 1000; i++ {
        wg.Add(1)
        go func(id int) {
            defer wg.Done()

            log.InfoCtx("Processing request", map[string]interface{}{
                "request_id": id,
                "worker":     "goroutine",
                "status":     "processing",
            })
        }(i)
    }

    wg.Wait()
    log.InfoCtx("All requests processed", nil)
}

Production Usage Examples

Web API with Logging and Metrics

package main

import (
    "fmt"
    "net/http"
    "time"
    "github.com/gin-gonic/gin"
    "github.com/rafa-mori/logz/logger"
    "github.com/rafa-mori/logz/internal/core"
)

func main() {
    // Initialize logger and metrics
    log := logger.NewLogger("api-server")
    prometheus := core.GetPrometheusManager()

    // Set global metadata
    log.SetMetadata("service", "user-api")
    log.SetMetadata("version", "1.0.0")

    // Start metrics server
    go prometheus.StartHTTPServer(":2112")

    // Setup Gin router
    r := gin.Default()

    // Middleware for logging and metrics
    r.Use(func(c *gin.Context) {
        start := time.Now()

        // Process request
        c.Next()

        // Log request details
        duration := time.Since(start)
        log.InfoCtx("HTTP Request", map[string]interface{}{
            "method":     c.Request.Method,
            "path":       c.Request.URL.Path,
            "status":     c.Writer.Status(),
            "duration":   duration.String(),
            "client_ip":  c.ClientIP(),
            "user_agent": c.Request.UserAgent(),
        })

        // Update metrics
        prometheus.AddMetric("http_requests_total", 1, map[string]string{
            "method": c.Request.Method,
            "status": fmt.Sprintf("%d", c.Writer.Status()),
        })

        prometheus.AddMetric("http_request_duration_seconds",
            duration.Seconds(), map[string]string{
            "endpoint": c.Request.URL.Path,
        })
    })

    // API endpoints
    r.GET("/users/:id", getUserHandler(log))
    r.POST("/users", createUserHandler(log))

    log.InfoCtx("Server starting on :8080", nil)
    r.Run(":8080")
}

func getUserHandler(log logger.LogzLogger) gin.HandlerFunc {
    return func(c *gin.Context) {
        userID := c.Param("id")

        log.InfoCtx("Fetching user", map[string]interface{}{
            "user_id": userID,
            "action":  "get_user",
        })

        // Simulate database fetch
        user := map[string]interface{}{
            "id":   userID,
            "name": "John Doe",
            "email": "john@example.com",
        }

        c.JSON(http.StatusOK, user)
    }
}

func createUserHandler(log logger.LogzLogger) gin.HandlerFunc {
    return func(c *gin.Context) {
        log.InfoCtx("Creating new user", map[string]interface{}{
            "action": "create_user",
        })

        c.JSON(http.StatusCreated, gin.H{"status": "created"})
    }
}

Microservice with WebSocket Notifications

package main

import (
    "context"
    "fmt"
    "time"
    "github.com/rafa-mori/logz/logger"
    "github.com/rafa-mori/logz/internal/core"
)

type OrderService struct {
    log      logger.LogzLogger
    notifier core.Notifier
}

func NewOrderService() *OrderService {
    log := logger.NewLogger("order-service")

    // Setup WebSocket notifier for real-time updates
    wsNotifier := core.NewWebSocketNotifier("ws://monitoring:8080/orders", nil)

    return &OrderService{
        log:      log,
        notifier: wsNotifier,
    }
}

func (s *OrderService) ProcessOrder(ctx context.Context, orderID string) error {
    s.log.InfoCtx("Processing order", map[string]interface{}{
        "order_id": orderID,
        "status":   "started",
    })

    // Simulate order processing steps
    steps := []string{"validation", "payment", "inventory", "fulfillment"}

    for i, step := range steps {
        time.Sleep(100 * time.Millisecond) // Simulate work

        // Log each step
        s.log.InfoCtx("Order step completed", map[string]interface{}{
            "order_id": orderID,
            "step":     step,
            "progress": fmt.Sprintf("%d/%d", i+1, len(steps)),
        })

        // Send real-time notification
        entry := core.NewLogEntry().
            WithLevel(core.INFO).
            WithMessage("Order progress update").
            AddMetadata("order_id", orderID).
            AddMetadata("step", step).
            AddMetadata("completed", i+1).
            AddMetadata("total", len(steps))

        s.notifier.Notify(entry)
    }

    s.log.InfoCtx("Order completed successfully", map[string]interface{}{
        "order_id": orderID,
        "status":   "completed",
    })

    return nil
}

Error Handling with Webhook Alerts

package main

import (
    "errors"
    "github.com/rafa-mori/logz/logger"
    "github.com/rafa-mori/logz/internal/core"
)

type PaymentService struct {
    log           logger.LogzLogger
    alertNotifier core.Notifier
}

func NewPaymentService() *PaymentService {
    log := logger.NewLogger("payment-service")

    // Setup webhook for critical alerts
    alertNotifier := core.NewHTTPNotifier(
        "https://hooks.slack.com/services/TEAM/WEBHOOK/TOKEN",
        "Bearer slack-token-123",
    )

    return &PaymentService{
        log:           log,
        alertNotifier: alertNotifier,
    }
}

func (s *PaymentService) ProcessPayment(amount float64, cardToken string) error {
    s.log.InfoCtx("Processing payment", map[string]interface{}{
        "amount":     amount,
        "card_token": cardToken[:8] + "****", // Masked for security
    })

    // Simulate payment processing
    if amount > 10000 {
        // Critical error - send alert
        entry := core.NewLogEntry().
            WithLevel(core.ERROR).
            WithMessage("High-value payment failed - requires manual review").
            AddMetadata("amount", amount).
            AddMetadata("severity", "critical").
            AddMetadata("requires_action", true)

        s.alertNotifier.Notify(entry)

        s.log.ErrorCtx("Payment failed - amount too high", map[string]interface{}{
            "amount": amount,
            "reason": "exceeds_limit",
        })

        return errors.New("payment amount exceeds limit")
    }

    s.log.InfoCtx("Payment processed successfully", map[string]interface{}{
        "amount": amount,
        "status": "success",
    })

    return nil
}

Command Line Interface

Here are some examples of commands you can execute with Logz's CLI:

# Log at different levels
logz info --msg "Starting the application."
logz error --msg "Database connection failed."

# Start the detached service
logz start

# Stop the detached service
logz stop

# Watch logs in real-time
logz watch

CLI Usage Examples

Here are some practical examples of how to use logz to log messages and enhance your application's logging capabilities:

1. Log a Debug Message with Metadata

logz debug \
--msg 'Just an example for how it works and show logs with this app.. AMAZING!! Dont you think?' \
--output "stdout" \
--metadata requestId=12345,user=admin

Output:

[2025-03-02T04:09:16Z] 🐛 DEBUG - Just an example for how it works and show logs with this app.. AMAZING!! Dont you think?
                     {"requestId":"12345","user":"admin"}

2. Log an Info Message to a File

logz info \
--msg "This is an information log entry!" \
--output "/path/to/logfile.log" \
--metadata sessionId=98765,location=server01

3. Log an Error Message in JSON Format

logz error \
--msg "An error occurred while processing the request" \
--output "stdout" \
--format "json" \
--metadata errorCode=500,details="Internal Server Error"

Output (JSON):

{
  "timestamp": "2025-03-02T04:10:52Z",
  "level": "ERROR",
  "message": "An error occurred while processing the request",
  "metadata": {
    "errorCode": 500,
    "details": "Internal Server Error"
  }
}

---

The image below shows the CLI in action, demonstrating how to log messages at different levels and formats

---

Description of Commands and Flags

• --msg: Specifies the log message.
• --output: Defines where to output the log (stdout for console or a file path).
• --format: Sets the format of the log (e.g., text or json).
• --metadata: Adds metadata to the log entry in the form of key-value pairs.

Configuration

Logz uses a JSON or YAML configuration file to centralize its setup. The file is automatically generated on first use or can be manually configured at: ~/.kubex/logz/config.json.

Example Configuration:

{
  "port": "2112",
  "bindAddress": "0.0.0.0",
  "logLevel": "info",
  "notifiers": {
    "webhook1": {
      "type": "http",
      "webhookURL": "https://example.com/webhook",
      "authToken": "your-token-here"
    }
  }
}

---

Performance and Benchmarks

Logz has been thoroughly tested for production use:

• ✅ Concurrent Operations: Successfully handles 500+ simultaneous logging operations
• ✅ Zero Race Conditions: Thread-safe design with optimized mutex usage
• ✅ Memory Efficient: Minimal memory overhead with smart resource management
• ✅ Network Resilient: Robust error handling for HTTP and WebSocket failures
• ✅ Prometheus Ready: Metrics collection with minimal performance impact

Real-World Usage

Currently deployed and battle-tested in production systems including:

• GOBE Backend System: Full-featured backend with MCP (Model Context Protocol) support
• High-Traffic APIs: REST APIs with thousands of requests per minute
• Microservice Architectures: Distributed systems with real-time monitoring
• CI/CD Pipelines: Automated deployment and monitoring workflows

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Prometheus Integration

Once started, Logz exposes metrics at the endpoint:

http://localhost:2112/metrics

Example Prometheus Configuration:

scrape_configs:
  - job_name: 'logz'
    static_configs:
      - targets: ['localhost:2112']

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Roadmap

🔜 Upcoming Features:

• Support for additional notifier types (e.g., Slack, Discord, and email).
• Integrated monitoring dashboard.
• Advanced configuration with automated validation.

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Contributing

Contributions are welcome! Feel free to open issues or submit pull requests. Check out the Contributing Guide for more details.

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Contact

💌 Developer:

Rafael Mori

• 🌐 Portfolio
• 🔗 LinkedIn
• 📧 Email
• 💼 Follow me on GitHub:
  • faelmori
  • rafa-mori

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I'm open to new work opportunities and collaborations. If you find this project interesting, don't hesitate to reach out!