Logging in colorSpec package

Description

There is some flexibility in the colorSpec logging level and format. Logging output goes to stderr(), just like the message stream; but see sink() (and the pitfalls of using it).

Logging Options

colorSpec.loglevel

The levels are: "FATAL", "ERROR", "WARN", "INFO", "DEBUG", and "TRACE" - the usual ones from Log4j. The initial level is "WARN". A "FATAL" event usually means an internal package error. When setting colorSpec.loglevel an initial letter is sufficient.

colorSpec.logformat

The format is given by a string with standard Log4j conversion specifications:

%t	the date/time of the logging event.	%t can be followed by standard strftime specs in braces; see example.
%l	the level of the logging event
%n	namespace where event occurred
%f	function where event occurred
%m	the message itself

colorSpec.stoponerror

If the this option is TRUE (the default), a log event with level "ERROR" stops execution; otherwise, execution keeps going. For interactive use, TRUE is probably better. For long batch jobs, FALSE might be appropriate, since then a single error may not force a complete repeat.
A "FATAL" event always stops execution.

References

Wikipedia. Log4j. https://en.wikipedia.org/wiki/Log4j

See Also

options, cs.options, sink, stderr

Examples

options( colorSpec.logformat="%t{%H:%M:%OS3} %l %n::%f(). %m", colorSpec.stoponerror=TRUE )

# or equivalently
cs.options( logformat="%t{%H:%M:%OS3} %l %n::%f(). %m", stop=TRUE )