Presented at Cocoaheads Copenhagen on 13 Februrary 2014

1. CocoaLumberjack

2. Hi!
I’m
Kristian
@ksmandersen

5. CocoaLumberjack

6. Why?
•
NSLog is inflexible
•
NSLog is slow
•
NSLog has no levels

7. Performance
“[…] I switched out all the logging statements
from using NSLog to use CocoaLumberjacks DDLog
instead, and saw an increase in performance of
almost 6x […]”

8. Performance
“[…] I switched out all the logging statements
from using NSLog to use CocoaLumberjacks DDLog
instead, and saw an increase in performance of
almost 6x […]”

9. Performance
1. Open a new connection to ASL daemon
2. Send message to ASL daemon
3. Close that connection
4. Write the same message to STDERR
5. for each NSLog statement: GOTO 1;

10. CocoaLumberjack
•
Multiple outputs
•
Different logging levels
•
Much faster!
•
Very flexible

11. Getting started
[DDLog addLogger:[DDTTYLogger sharedInstance]];

12. LEVELS
DDLogError(@"Some error %@, %@", error, error.userInfo);
DDLogWarn(@"Unexpected thing");
DDLogInfo(@"Heads up here");
DDLogDebug(@"Bug bug debug");
DDLogVerbose(@"Extreme verbosity");

13. Replacing NSLOG
// Making NSLog use Cocoa Lumberjack
#define NSLog DDLogInfo

14. Replacing NSLOG
// Making NSLog use Cocoa Lumberjack
#define NSLog DDLogInfo

15. Colors
https://github.com/robbiehanson/XcodeColors

16. AFNetworking
AFNetworkActivityLogger *logger =
[AFNetworkActivityLogger sharedLogger];
!
[logger setLevel:AFLoggerLevelInfo]];
[logger startLogging];

17. AFNetworking
GET http://example.com/foo/bar.json
200 http://example.com/foo/bar.json
!
POST http://example.com/other/url.json
503 http://example.com/other/url.json

18. Crashlytics
[DDLog addLogger:[CrashlyticsLogger sharedInstance]];

19. Formatters
DDLogError(@"Paper Jam!");
DDLogWarn(@"Low toner.");
DDLogInfo(@"Doc printed.");
DDLogDebug(@"Debugging");
DDLogVerbose(@"Init doc_parse");
//
//
//
//
//
E
W
I
D
V
|
|
|
|
|
Paper Jam!
Low toner.
Doc printed.
Debugging
Init doc_parse.

20. Formatters
- (NSString *)formatLogMessage:(DDLogMessage *)logMessage
{
NSString *logLevel;
switch (logMessage->logFlag)
{
case LOG_FLAG_ERROR : logLevel = @"E"; break;
case LOG_FLAG_WARN : logLevel = @"W"; break;
case LOG_FLAG_INFO : logLevel = @"I"; break;
case LOG_FLAG_DEBUG : logLevel = @"D"; break;
default
: logLevel = @"V"; break;
}
return [NSString stringWithFormat:@"%@ | %@n",
logLevel, logMessage->logMsg];
}

21. Per logger levels
[DDLog addLogger:[DDTTYLogger sharedInstance]
withLogLevel:LOG_LEVEL_INFO];

22. PER CLASS LEVEL
+ (NSArray *)registeredClasses;
+ (NSArray *)registeredClassNames;
!
+ (int)logLevelForClass:(Class)aClass;
+ (int)logLevelForClassWithName:(NSString *)aClassName;
!
+ (void)setLogLevel:(int)logLevel
forClass:(Class)aClass;
+ (void)setLogLevel:(int)logLevel
forClassWithName:(NSString *)aClassName;

23. App broken w/ no
crash

24. App broken w/ no
crash

25. Rolling Logs
DDFileLogger *fileLogger = [[DDFileLogger alloc] init];
!
[fileLogger setRollingFrequency:60 * 60 * 24];
[fileLogger setMaximumFileSize:1024 * 1024 * 2];
[fileLogger.logFileManager setMaximumNumberOfLogFiles:7];
[DDLog addLogger:fileLogger];

26. DEMO

27. Questions?
@ksmandersen

28. jobs.robo.cat