A little hack to work comfortably with cocoa lumberjack in Swift.

Readme.md

CocoaLumberjack.swift

Prerequisites

This assumes you have the CocoaLumberjack pod in your Podfile (tested with 2.0.0-beta)
Also import CocoaLumberjack/DDLog.h and CocoaLumberjack/DDTTYLogger.h in your bridging header

Configuring the loggin

• As usual add all the loggers you might want/need: DDLog.addLogger(DDTTYLogger.sharedInstance())
• Configure the log level like so: DDLog.logLevel = .Info
• Log away :)
• You might also want to enable/disable async logging: DDLog.logAsync = false

License

This Gist is under MIT

CocoaLumberjack.swift

//  Created by Ullrich Schäfer on 16/08/14.


// Bitmasks are a bit tricky in swift
// See http://natecook.com/blog/2014/07/swift-options-bitmask-generator/

//enum LogFlag: Int32 {
//    case Error   = 0b1
//    case Warn    = 0b10
//    case Info    = 0b100
//    case Debug   = 0b1000
//    case Verbose = 0b10000
//}

struct LogFlag : RawOptionSetType {
    private var value: Int32 = 0
    init(_ value: Int32) { self.value = value }
    var boolValue: Bool { return self.value != 0 }
    func toRaw() -> Int32 { return self.value }
    static func fromRaw(raw: Int32) -> LogFlag? { return self(raw) }
    static func fromMask(raw: Int32) -> LogFlag { return self(raw) }
    static func convertFromNilLiteral() -> LogFlag { return self(0) }
    
    static var Error:   LogFlag { return self(1 << 0) }
    static var Warn:    LogFlag { return self(1 << 1) }
    static var Info:    LogFlag { return self(1 << 2) }
    static var Debug:   LogFlag { return self(1 << 3) }
    static var Verbose: LogFlag { return self(1 << 4) }
}
func == (lhs: LogFlag, rhs: LogFlag) -> Bool { return lhs.value == rhs.value }



//enum LogLevel: Int32 {
//    case Off     = 0b0
//    case Error   = 0b1
//    case Warn    = 0b11
//    case Info    = 0b111
//    case Debug   = 0b1111
//    case Verbose = 0b11111
//    case All     = 0bFFFFFFFF // 1111....11111 (LOG_LEVEL_VERBOSE plus any other flags)
//}

struct LogLevel : RawOptionSetType {
    private var value: Int32 = 0
    init(_ value: Int32) { self.value = value }
    var boolValue: Bool { return self.value != 0 }
    func toRaw() -> Int32 { return self.value }
    static func fromRaw(raw: Int32) -> LogLevel? { return self(raw) }
    static func fromMask(raw: Int32) -> LogLevel { return self(raw) }
    static func convertFromNilLiteral() -> LogLevel { return self(0) }
    
    static var Off:     LogLevel { return self(0b0) }
    static var Error:   LogLevel { return self(0b1) }
    static var Warn:    LogLevel { return self(0b11) }
    static var Info:    LogLevel { return self(0b111) }
    static var Debug:   LogLevel { return self(0b1111) }
    static var Verbose: LogLevel { return self(0b11111) }
    static var All:     LogLevel { return self(0b11111111) }
}
func == (lhs: LogLevel, rhs: LogLevel) -> Bool { return lhs.value == rhs.value }



// what's a better way than poluting the global scope?
var __logLevel: LogLevel?
var __logAsync: Bool?


// Use those class properties insted of `#define LOG_LEVEL_DEF` and `LOG_ASYNC_ENABLED`
extension DDLog {
    class var logLevel: LogLevel {
        get {
            return __logLevel ?? LogLevel.Error
        }
        set(logLevel) {
            __logLevel = logLevel
        }
    }
    
    class var logAsync: Bool {
        get {
            return (self.logLevel != LogLevel.Error) && (__logAsync ?? true)
        }
        set(logAsync) {
            __logAsync = logAsync
        }
    }
    
    class func logError (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { log(.Error, message: message, function: function, file: file, line: line) }
    class func logWarn  (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { log(.Warn,  message: message, function: function, file: file, line: line) }
    class func logInfo  (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { log(.Info,  message: message, function: function, file: file, line: line) }
    class func logDebug (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { log(.Debug, message: message, function: function, file: file, line: line) }
    
    private class func log (
        flag: LogFlag,
        message: String,
        // No need to pass those in. the defaults will do just fine
        function: String = __FUNCTION__,
        file: String = __FILE__,
        line: Int32 = __LINE__
        )
    {
        let level:LogLevel = DDLog.logLevel
        let async:Bool = (level != LogLevel.Error) && DDLog.logAsync
        
        if flag.toRaw() & level.toRaw() != 0 {
            DDLog.log(
                async,
                message: DDLogMessage(logMsg: message,
                    level: level.toRaw(),
                    flag: flag.toRaw(),
                    context: 0,
                    file: file,
                    function: function,
                    line: line,
                    tag: nil,
                    options: 0))
        }
    }
}

// Shorthands, what you'd expect
/* //Not possible due to http://openradar.appspot.com/radar?id=5773154781757440
let logError = DDLog.logError
let logWarn  = DDLog.logWarn
let logInfo  = DDLog.logInfo
let logDebug = DDLog.logDebug
*/
func logError (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { DDLog.logError(message, function: function, file: file, line: line) }
func logWarn  (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { DDLog.logWarn(message, function: function, file: file, line: line) }
func logInfo  (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { DDLog.logInfo(message, function: function, file: file, line: line) }
func logDebug (message: String, function: String = __FUNCTION__, file: String = __FILE__, line: Int32 = __LINE__) { DDLog.logDebug(message, function: function, file: file, line: line) }

I have problems with Xcode 6 beta 6 while compiling.
on line 15 and 44 compiles shows this error:

.../Sources/CocoaLumberjack.swift:15:1: Type 'LogFlag' does not conform to protocol 'BitwiseOperationsType'
.../Swift.BitwiseOperationsType:16:13: Protocol requires property 'allZeros' with type 'LogFlag'

Yep, same problem with Xcode 6 Beta 7

Yup, the protocal for RawOptionSetType changed.

Fixed it in a Gist here: https://gist.github.com/depl0y/b46bbf5bd2d236597e39

Ofcourse I left the "Created by" in there @stigi

Also, when async in enabled, variables as __FUNCTION__ do not work as expected, turn it off.

DDLog.logAsync = false;

Fix to conform with latest (6.1 GM Seed) protocol

https://gist.github.com/metalik/99a73d5ef5ab0fa0418c

Updated to Swift 1.1, also stored logLevel/logAsync in embedded struct statics:
https://gist.github.com/cfr/7da8da56654288fad7aa

How is this going to avoid evaluating the "message" when logging is disabled / the log level is lower, like the macros do?

Shouldn't it be using @autoclosure and treating the message as a () -> (String) closure to make this possible?

How do I actually log anything using this extension?