OSLogging

OSLog logging backend for swift-log

• WWDC 2016 Unified Logging and Activity Tracing
• logs can be seen in Console.app

Features

• Configure OSLog
• Mapping logging levels of Logger.Level to OSLogType
• Customize metadata formatter

Instalation

Add dependency to Package.swift…

.package(url: "https://github.com/Alexander-Ignition/OSLogging", from: "1.0.0"),

… and your target

.target(name: "ExampleApp", dependencies: ["OSLogging"]),

Usage

Override LoggingSystem with default OSLog.

LoggingSystem.bootstrap { _ in OSLogHandler() }

let logger = Logger(label: "com.example.app")
logger.info("i found you!")
// 2019-10-20 08:47:35.498086+0300 ExampleApp[6533:150683] i found you!

Сhoose subsystems and categories for different parts of the application

let logger = Logger(label: "com.exaple.app") { label in
    OSLogHandler(subsystem: label, category: "auth")
}

logger.info("loose control")
// 2019-10-20 08:47:35.498582+0300 ExampleApp[6533:150683] [auth] loose control

Custom metadata format

var logger = Logger(label: "com.exaple.app") { label in
    var hanlder = OSLogHandler(subsystem: label, category: "session")
    hanlder.formatter = { metadata in
        metadata.map { "\($0):\($1)" } .joined(separator: ", ")
    }
    return hanlder
}
logger[metadataKey: "request-id"] = "1"
logger[metadataKey: "session-id"] = "a"

logger.warning("catch me if you can")
// 2019-10-20 08:47:35.499106+0300 ExampleApp[6533:150683] [session] session-id:a, request-id:1 catch me now