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