swift-log+SwiftyBeaver

example.swift

var logger = Logger(label: Bundle.main.bundleIdentifier!)

SwiftyBeaver.self.addDestination(ConsoleDestination())
SwiftyBeaver.self.addDestination(FileDestination())
LoggingSystem.bootstrap(SwiftyBeaverLogHandler.init)

#if DEBUG
logger.logLevel = .debug
#endif

logger.debug("test")

SwiftyBeaverLogHandler.swift

import Logging
import SwiftyBeaver

struct SwiftyBeaverLogHandler: LogHandler {
    var metadata: Logger.Metadata = .init()

    var logLevel: Logger.Level = .info

    init(_: String) {
    }

    func log(level: Logger.Level, message: Logger.Message, metadata: Logger.Metadata?, file: String, function: String, line: UInt) {
        SwiftyBeaver.self.custom(level: level.asSwiftyBeaverLevel,
                                 message: message,
                                 file: file,
                                 function: function,
                                 line: Int(line),
                                 context: metadata)
    }

    subscript(metadataKey metadataKey: String) -> Logger.Metadata.Value? {
        get {
            metadata[metadataKey]
        }
        set {
            metadata[metadataKey] = newValue
        }
    }
}

private extension Logger.Level {
    var asSwiftyBeaverLevel: SwiftyBeaver.Level {
        switch self {
        case .trace:
            return .verbose
        case .debug:
            return .debug
        case .info:
            return .info
        case .notice:
            return .warning
        case .warning:
            return .warning
        case .error:
            return .error
        case .critical:
            return .error
        }
    }
}