CocoaLumberjack

CocoaLumberjack is a fast & simple, yet powerful & flexible logging framework for macOS, iOS, tvOS and watchOS.

How to get started

First, install CocoaLumberjack via CocoaPods, Carthage, Swift Package Manager or manually. Then use DDOSLogger for iOS 10 and later, or DDTTYLogger and DDASLLogger for earlier versions to begin logging messages.

CocoaPods

platform :ios, '9.0'

target 'SampleTarget' do
  use_frameworks!
  pod 'CocoaLumberjack/Swift'
end

Note: Swift is a subspec which will include all the Obj-C code plus the Swift one, so this is sufficient. For more details about how to use Swift with Lumberjack, see this conversation.

For Objective-C use the following:

platform :ios, '9.0'

target 'SampleTarget' do
    pod 'CocoaLumberjack'
end

Carthage

Carthage is a lightweight dependency manager for Swift and Objective-C. It leverages CocoaTouch modules and is less invasive than CocoaPods.

To install with Carthage, follow the instruction on Carthage

Cartfile

github "CocoaLumberjack/CocoaLumberjack"

Swift Package Manager

As of CocoaLumberjack 3.6.0, you can use the Swift Package Manager as integration method. If you want to use the Swift Package Manager as integration method, either use Xcode to add the package dependency or add the following dependency to your Package.swift:

.package(url: "https://github.com/CocoaLumberjack/CocoaLumberjack.git", from: "3.7.0"),

Note that you may need to add both products, CocoaLumberjack and CocoaLumberjackSwift to your target since SPM sometimes fails to detect that CocoaLumerjackSwift depends on CocoaLumberjack.

Install manually

If you want to install CocoaLumberjack manually, read the manual installation guide for more information.

Swift Usage

Usually, you can simply import CocoaLumberjackSwift. If you installed CocoaLumberjack using CocoaPods, you need to use import CocoaLumberjack instead.

DDLog.add(DDOSLogger.sharedInstance) // Uses os_log

let fileLogger: DDFileLogger = DDFileLogger() // File Logger
fileLogger.rollingFrequency = 60 * 60 * 24 // 24 hours
fileLogger.logFileManager.maximumNumberOfLogFiles = 7
DDLog.add(fileLogger)

...

DDLogVerbose("Verbose")
DDLogDebug("Debug")
DDLogInfo("Info")
DDLogWarn("Warn")
DDLogError("Error")

Obj-C usage

If you're using Lumberjack as a framework, you can @import CocoaLumberjack;. Otherwise, #import <CocoaLumberjack/CocoaLumberjack.h>

[DDLog addLogger:[DDOSLogger sharedInstance]]; // Uses os_log

DDFileLogger *fileLogger = [[DDFileLogger alloc] init]; // File Logger
fileLogger.rollingFrequency = 60 * 60 * 24; // 24 hour rolling
fileLogger.logFileManager.maximumNumberOfLogFiles = 7;
[DDLog addLogger:fileLogger];

...

DDLogVerbose(@"Verbose");
DDLogDebug(@"Debug");
DDLogInfo(@"Info");
DDLogWarn(@"Warn");
DDLogError(@"Error");

Objective-C ARC Semantic Issue

When integrating Lumberjack into an existing Objective-C it is possible to run into Multiple methods named 'tag' found with mismatched result, parameter type or attributes build error.

Add #define DD_LEGACY_MESSAGE_TAG 0 before importing CocoaLumberjack or add #define DD_LEGACY_MESSAGE_TAG 0 or add -DDD_LEGACY_MESSAGE_TAG=0 to Other C Flags/OTHER_CFLAGS in your Xcode project.

swift-log backend

CocoaLumberjack also ships with a backend implementation for swift-log. Simply add CocoaLumberjack as dependency to your SPM target (see above) and also add the CocoaLumberjackSwiftLogBackend product as dependency to your target.

You can then use DDLogHandler as backend for swift-log, which will forward all messages to CocoaLumberjack's DDLog. You will still configure the loggers and log formatters you want via DDLog, but writing log messages will be done using Logger from swift-log.

In your own log formatters, you can make use of the swiftLogInfo property on DDLogMessage to retrieve the details of a message that is logged via swift-log.

To use swift-log with CocoaLumberjack, take a look the following code snippet to see how to get started.

// Import necessary packages
import CocoaLumberjackSwift
import CocoaLumberjackSwiftLogBackend
import Logging

// In your application's entry point (e.g. AppDelegate):
DDLog.add(DDOSLogger.sharedInstance) // Configure loggers
LoggingSystem.bootstrapWithCocoaLumberjack() // Use CocoaLumberjack as swift-log backend

More information

read the Getting started guide, check out the FAQ section or the other docs
if you find issues or want to suggest improvements, create an issue or a pull request
for all kinds of questions involving CocoaLumberjack, use the Google group or StackOverflow (use #lumberjack).

CocoaLumberjack 3

Migrating to 3.x

To be determined

Features

Lumberjack is Fast & Simple, yet Powerful & Flexible.

It is similar in concept to other popular logging frameworks such as log4j, yet is designed specifically for Objective-C, and takes advantage of features such as multi-threading, grand central dispatch (if available), lockless atomic operations, and the dynamic nature of the Objective-C runtime.

Lumberjack is Fast

In most cases it is an order of magnitude faster than NSLog.

Lumberjack is Simple

It takes as little as a single line of code to configure lumberjack when your application launches. Then simply replace your NSLog statements with DDLog statements and that's about it. (And the DDLog macros have the exact same format and syntax as NSLog, so it's super easy.)

Lumberjack is Powerful:

One log statement can be sent to multiple loggers, meaning you can log to a file and the console simultaneously. Want more? Create your own loggers (it's easy) and send your log statements over the network. Or to a database or distributed file system. The sky is the limit.

Lumberjack is Flexible:

Configure your logging however you want. Change log levels per file (perfect for debugging). Change log levels per logger (verbose console, but concise log file). Change log levels per xcode configuration (verbose debug, but concise release). Have your log statements compiled out of the release build. Customize the number of log levels for your application. Add your own fine-grained logging. Dynamically change log levels during runtime. Choose how & when you want your log files to be rolled. Upload your log files to a central server. Compress archived log files to save disk space...

This framework is for you if:

You're looking for a way to track down that impossible-to-reproduce bug that keeps popping up in the field.
You're frustrated with the super short console log on the iPhone.
You're looking to take your application to the next level in terms of support and stability.
You're looking for an enterprise level logging solution for your application (Mac or iPhone).

Documentation

Requirements

The current version of Lumberjack requires:

Xcode 12 or later
Swift 5.3 or later
iOS 9 or later
macOS 10.10 or later
watchOS 3 or later
tvOS 9 or later

Backwards compatibility

for Xcode 11 and Swift up to 5.2, use the 3.6.2 version
for Xcode 10 and Swift 4.2, use the 3.5.2 version
for iOS 8, use the 3.6.1 version
for iOS 6, iOS 7, OS X 10.8, OS X 10.9 and Xcode 9, use the 3.4.2 version
for iOS 5 and OS X 10.7, use the 3.3 version
for Xcode 8 and Swift 3, use the 3.2 version
for Xcode 7.3 and Swift 2.3, use the 2.4.0 version
for Xcode 7.3 and Swift 2.2, use the 2.3.0 version
for Xcode 7.2 and 7.1, use the 2.2.0 version
for Xcode 7.0 or earlier, use the 2.1.0 version
for Xcode 6 or earlier, use the 2.0.x version
for OS X < 10.7 support, use the 1.6.0 version

Communication

If you need help, use Stack Overflow. (Tag 'lumberjack')
If you'd like to ask a general question, use Stack Overflow.
If you found a bug, open an issue.
If you have a feature request, open an issue.
If you want to contribute, submit a pull request.

Data Collection Practices

Per App privacy details on the App Store, Apple is requesting app developers to provide info about their data collection, us SDK maintainers must provide them with the same data.

Data collection by the framework

By default, CocoaLumberjack does NOT collect any data on its own.

See our Data Collection Practices list.

Indirect data collection through the framework

CocoaLumberjack is a logging framework which makes it easy to send those logs to different platforms.

This is why collecting data might happen quite easily, if app developers include any sensitive data into their log messages.

Important note: app developers are fully responsible for any sensitive data collected through our logging system!

In consequence, you must comply to the Apple's privacy details policy (mentioned above) and document the ways in which user data is being collected. Since the number of scenarios where data might be indirectly collected through CocoaLumberjack is quite large, it's up to you, as app developers, to properly review your app's code and identify those cases. What we can do to help is raise awareness about potential data collection through our framework.

Private data includes but isn't limited to:

user info (name, email, address, ...)
location info
contacts
identifiers (user id, device id, ...)
app usage data
performance data
health and fitness info
financial info
sensitive info
user content
history (browsing, search, ...)
purchases
diagnostics
...

Example: DDLogInfo("User: \(myUser)") will add the myUser info to the logs, so if those are forwarded to a 3rd party or sent via email, that may qualify as data collection.

mackworth/CocoaLumberjack