Toothpick is a simple logging framework for Smalltalk that separates the concerns of whether, where, and what to log. It includes loggers to define where events are logged, like to the transcript, files, or network. Logging formatters define what is logged, like simple text or XML. Logging policies determine whether an event is logged based on its category and level. The LoggingMultiplexer manages multiple loggers. LoggingEvents contain log messages that are sent to the multiplexer.

2. Toothpick –
a new logging framework for Smalltalk

3. What is Toothpick?
 A simple logging framework
 Separates events and concerns
 Whether to log
 Where to log
 What to log

4. Logger
 Defines where to log
 Transcript
 File
 Socket
 stdout, stderr
 NT event log
 Syslogd, IRC

5. Logger example
| logger1 logger2 |
logger1 := TranscriptLogger new
name: 'My first Logger'.
logger2 := FileLogger new
name: 'My second Logger';
fileName: 'MyLog.txt'.

6. LoggingFormatter
 Defines what (how) to log
 Simple text
 XML
 Pattern ( like printf() )
 Timestamp
 syslogd()
 Log4J 

7. LoggingFormatter example
| logger1 logger2 |
logger1 := TranscriptLogger new
format: SimpleLoggingFormatter defaultFormat.
logger2 := FileLogger new
fileName: ‘MyLog.txt’;
format: SimpleLoggingFormatter defaultFormat.

8. LoggingPolicy
 Defines whether to log an event
 Simple
 Composite
 Multiple event patterns
 Borrowed from syslogd()

9. #isInterestingBlock
LoggingPolicy>>#defaultIsInterestingBlock
^ [ :event | event category == self category and: [
event isLevelHigherThan: self level ]]

10. Categories and Levels
 Category may be any Symbol
 Levels predefined
LoggingEvent class>>#allLevels
^#(#all #debug #info #notice #warn #error #crit
#alert #emerg #panic #fatal #off #none)

11. LoggingPolicy example
| logger1 logger2 |
logger1 := TranscriptLogger new
format: SimpleLoggingFormatter defaultFormat;
policy: (LoggingPolicy category: #debug level: #info).
logger2 := FileLogger new
fileName: ‘MyLog.txt’;
format: SimpleLoggingFormatter defaultFormat;
policy: (LoggingPolicy category: #debug level: #debug).

12. LoggingMultiplexer
 Central log manager

13. LoggingMultiplexer example
| logger1 logger2 |
logger1 := TranscriptLogger new
format: SimpleLoggingFormatter defaultFormat;
policy: (LoggingPolicy category: #debug level: #info).
logger2 := FileLogger new
fileName: ‘MyLog.txt’;
format: SimpleLoggingFormatter defaultFormat;
policy: (LoggingPolicy category: #debug level: #debug).
LoggingMultiplexer current
addLogger: logger1;
addLogger: logger2;
startAllLoggers

14. LoggingEvent
 An item of interest
 Not related to the #triggerEvent: framework
 But can be very easily connected
 Information
 category, level, timestamp, message
 Can include context and exception info

15. Sending events
LoggingEvent
category: #debug
level: #warn
message: 'using obsolete protocol'.
LoggingEvent
category: #myapp
level: #debug
message: 'reading ini files'.

16. Configuration
 The framework can be configured from an
external file.
 The file can be re-read at run-time to
reconfigure the framework.

17. Where do I get this?
 http://www.metaprog.com/Toothpick