PrettyLogger

Introduction

A modern Swift logging library that integrates with Apple's unified logging system (OSLog) while maintaining a simple and familiar API. Provides structured logging with categories, privacy controls, and seamless integration with system debugging tools 💪

Platforms

Support for iOS 14.0+, tvOS 14.0+, watchOS 7.0+, and macOS 11.0+

Support

For Swift 4 please use v1

For Swift 5 please use v2-v3

For Swift 5.5+ with OSLog please use v4+

Installation

PrettyLogger is available through Swift Package Manager.

1. Follow Apple's Adding Package Dependencies to Your App guide on how to add a Swift Package dependency.
2. Use https://github.com/hyperdevs-team/PrettyLogger as the repository URL.
3. Specify the version to be at least 4.0.0.

Usage

Basic Logging

To log messages, simply use any of the global functions:

logFatal("Critical error occurred")
logError("Something went wrong")
logWarning("This is a warning")
logInfo("User logged in successfully")
logDebug("Processing user data")
logTrace("Entering function")

Logging with Categories

Organize your logs with categories for better filtering and debugging:

logInfo("API request started", category: "Network")
logError("Database connection failed", category: "Database")
logDebug("Cache hit for user data", category: "Cache")
logWarning("Low memory warning", category: "System")

Privacy Controls

Control the visibility of sensitive information in your logs:

let userEmail = "user@example.com"
let authToken = "abc123xyz"

// Public information (visible in all log viewers)
logInfo("App version 1.2.3", privacy: .public)

// Private information (hidden in release builds)
logDebug("User email: \(userEmail)", category: "Auth", privacy: .private)
logTrace("Auth token: \(authToken)", category: "Auth", privacy: .private)

// Auto privacy (system decides based on context) - Default behavior
logInfo("User logged in successfully", privacy: .auto)

Complete Examples

// Basic usage
logInfo("User authentication started")

// With category
logError("Network timeout occurred", category: "Network")

// With privacy
logDebug("Processing sensitive data", privacy: .private)

// With both category and privacy
logWarning("Failed login attempt", category: "Security", privacy: .private)

Note: Starting with version 4.0.0, PrettyLogger uses Apple's unified logging system (OSLog). This means logs are now visible not only in Xcode's console but also in system tools like Console.app, Instruments, and the command-line log tool, providing better integration with Apple's debugging ecosystem.

Log Levels

You can control which logs are shown by setting the level on the shared instance:

PrettyLogger.shared.level = .all      // Show all messages
PrettyLogger.shared.level = .disable  // Disable all logging
PrettyLogger.shared.level = .info     // Show info and above (hide debug & trace)
PrettyLogger.shared.level = .error    // Show only error and fatal messages

The available levels, in order from most restrictive to least restrictive, are: disable, fatal, error, warn, info, debug, trace, all

Real-time Log Monitoring

You can subscribe to log outputs for real-time monitoring or custom handling:

import Combine

var cancellables = Set<AnyCancellable>()

PrettyLogger.shared.output
    .sink { logOutput in
        print("Received log: \(logOutput.level) - \(logOutput.message)")
        // Send to analytics, crash reporting, etc.
    }
    .store(in: &cancellables)

Viewing Logs in System Tools

With version 4.0.0, you can view your app's logs in various Apple debugging tools:

• Xcode Console: Shows logs during development and debugging
• Console.app: System-wide log viewer with advanced filtering capabilities
• Instruments: Correlate logs with performance data
• Command Line: Use log show --predicate 'subsystem == "com.yourapp.bundleid"'

Global Framework Import

If you want to use logging functions throughout your project without importing PrettyLogger in every file, add this to your AppDelegate:

@_exported import PrettyLogger

Migration from v3 to v4

Version 4.0.0 introduces OSLog integration while maintaining the same familiar function names. The main changes are:

• Enhanced API: New optional category and privacy parameters
• Better Performance: Uses Apple's optimized logging system
• System Integration: Logs appear in Console.app, Instruments, and other system tools
• Privacy Controls: Built-in support for sensitive data handling

Your existing code will continue to work with deprecation warnings guiding you to the new API:

// v3 style (still works, but deprecated)
logInfo("User:", username, "logged in")

// v4 style (recommended)
logInfo("User: \(username) logged in", category: "Authentication")

Requirements

• iOS 14.0+ / tvOS 14.0+ / watchOS 7.0+ / macOS 11.0+
• Swift 5.5+
• Xcode 13.0+