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Jifty::Logger -- A master class for Jifty's logging framework


Jifty uses the Log4perl module to log error messages. In Jifty programs there's two ways you can get something logged:

Firstly, Jifty::Logger captures all standard warnings that Perl emits. So in addition to everything output from perl via the warnings pragmas, you can also log messages like so:

    warn("The WHAM is overheating!");

This doesn't give you much control however. The second way allows you to specify the level that you want logging to occur at:

    Jifty->log->debug("Checking the WHAM");
    Jifty->log->info("Potential WHAM problem detected");
    Jifty->log->warn("The WHAM is overheating");
    Jifty->log->fatal("Someone call Eddie Murphy!");

Configuring Log4perl

Unless you specify otherwise in the configuration file, Jifty will supply a default Log4perl configuration.

The default log configuration that logs all messages to the screen (i.e. to STDERR, be that directly to the terminal or to the FastCGI log file.) It will log all messages of equal or higher priority to the LogLevel configuration option.

      LogLevel: DEBUG

You can override the LogLevel configuration option by setting JIFTY_LOG_LEVEL in your environment.

You can tell Jifty to use an entirely different Logging configuration by specifying the filename of a standard Log4perl config file in the LogConfig config option (see Log::Log4perl for the format of this config file.)

      LogConfig: etc/log4perl.conf

Note that specifying your own config file prevents the LogLevel config option from having any effect.

You can tell Log4perl to check that file periodically for changes. This costs you a little in application performance, but allows you to change the logging level of a running application. You need to set LogReload to the frequency, in seconds, that the file should be checked.

      LogConfig: etc/log4perl.conf
      LogReload: 10

(This is implemented with Log4perl's init_and_watch functionality)



This class method instantiates a new Jifty::Logger object. This object deals with logging for the system.

Takes an optional name for this Jifty's logging "component" - See Log::Log4perl for some detail about what that is. It sets up a "warn" handler which logs warnings to the specified component.


change the Log4Perl action from warn to error|info|etc based on the content of the warning.

Added because DBD::Pg throws up NOTICE and other messages as warns, and we really want those to be info (or error, depending on the code). List based on Postgres documentation

TODO: needs to be smarter than just string matching

returns a valid Log::Log4Perl action, if nothing matches will return the default of warn since we're in a __WARN__ handler


Various folks at Best Practical Solutions, LLC.

Mark Fowler <> fiddled a bit.