Colorful, flexible, lightweight logging for Swift 5 & Swift 6.

Great for development & release with support for Console, file & cloud destinations for server-side Swift.

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During Development: Colored Logging to Xcode Console via OSLog API or Print

// use Apple's fancy OSLog API:
let console = ConsoleDestination()
console.logPrintWay = .logger(subsystem: "Main", category: "UI")

// or use good ol' "print" (which is the default):
let console = ConsoleDestination()
console.logPrintWay = .print

During Development: Colored Logging to File

Learn more about logging to file which is great for Terminal.app fans or to store logs on disk.

Google Cloud & More

You can fully customize your log format, turn it into JSON, or create your own destinations. For example, our Google Cloud Destination is just another customized logging format that adds the powerful functionality of automatic server-side Swift logging when hosted on Google Cloud Platform.

Installation

• For Swift 4 & 5 install the latest SwiftyBeaver version
• For Swift 3 install SwiftyBeaver 1.8.4
• For Swift 2 install SwiftyBeaver 0.7.0

Swift Package Manager

For Swift Package Manager add the following package to your Package.swift file. Just Swift 4 & 5 are supported:

.package(url: "https://github.com/SwiftyBeaver/SwiftyBeaver.git", .upToNextMajor(from: "2.0.0")),

Disable swift-log integration to avoid adding it as a dependency.

Set the SWIFT_LOG_INTEGRATION environment variable to NO or FALSE for any commands that resolve package dependencies.

SWIFT_LOG_INTEGRATION=FALSE swift build
SWIFT_LOG_INTEGRATION=FALSE swift test

Usage

SwiftyBeaver

Add that near the top of your AppDelegate.swift to be able to use SwiftyBeaver in your whole project.

import SwiftyBeaver
let log = SwiftyBeaver.self

At the beginning of your AppDelegate:didFinishLaunchingWithOptions() add the SwiftyBeaver log destinations (console, file, etc.), optionally adjust the log format and then you can already do the following log level calls globally:

// add log destinations. at least one is needed!
let console = ConsoleDestination()  // log to Xcode Console
let file = FileDestination()  // log to default swiftybeaver.log file

// use custom format and set console output to short time, log level & message
console.format = "$DHH:mm:ss$d $L $M"
// or use this for JSON output: console.format = "$J"

// In Xcode 15, specifying the logging method as .logger to display color, subsystem, and category information in the console.(Relies on the OSLog API)
console.logPrintWay = .logger(subsystem: "Main", category: "UI")
// If you prefer not to use the OSLog API, you can use print instead.
// console.logPrintWay = .print

// add the destinations to SwiftyBeaver
log.addDestination(console)
log.addDestination(file)

// Now let’s log!
log.verbose("not so important")  // prio 1, VERBOSE in silver
log.debug("something to debug")  // prio 2, DEBUG in green
log.info("a nice information")   // prio 3, INFO in blue
log.warning("oh no, that won’t be good")  // prio 4, WARNING in yellow
log.error("ouch, an error did occur!")  // prio 5, ERROR in red

// log anything!
log.verbose(123)
log.info(-123.45678)
log.warning(Date())
log.error(["I", "like", "logs!"])
log.error(["name": "Mr Beaver", "address": "7 Beaver Lodge"])

// optionally add context to a log message
console.format = "$L: $M $X"
log.debug("age", context: 123)  // "DEBUG: age 123"
log.info("my data", context: [1, "a", 2]) // "INFO: my data [1, \"a\", 2]"

Alternatively, if you are using SwiftUI, consider using the following setup:

import SwiftyBeaver
let logger = SwiftyBeaver.self

@main
struct yourApp: App {

    init() {
        let console = ConsoleDestination()
        logger.addDestination(console)
        // etc...
    }

    var body: some Scene {
        WindowGroup {
        }
    }
}

swift-log Integration with SwiftyBeaverSwiftLog

SwiftyBeaver can be used through swift-log with the SwiftyBeaverSwiftLog target.

In the same place you add your destinations to SwiftyBeaver you can boostratp LoggingSystem as shown:

import Logging
import SwiftyBeaver
import SwiftyBeaverSwiftLog
LoggingSystem.bootstrap { label in
    SwiftyBeaverLogHandler(metadata: ["label": .string(label)])
}

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Server-side Swift

We ❤️ server-side Swift and SwiftyBeaver support it out-of-the-box! Try for yourself and run SwiftyBeaver inside a Ubuntu Docker container. Just install Docker and then go to your project folder on macOS or Ubuntu and type:

# create docker image, build SwiftyBeaver and run unit tests
docker run --rm -it -v $PWD:/app swiftybeaver /bin/bash -c "cd /app ; swift build ; swift test"

# optionally log into container to run Swift CLI and do more stuff
docker run --rm -it --privileged=true -v $PWD:/app swiftybeaver

Best: for the popular server-side Swift web framework Vapor you can use our Vapor logging provider which makes server logging awesome again 🙌

Documentation

Getting Started:

• Features
• Installation
• Basic Setup

Logging Destinations:

• Colored Logging to Xcode Console
• Colored Logging to File

Advanced Topics:

• Custom Format & Context
• Filters

License

SwiftyBeaver Framework is released under the MIT License.