Author image David R. Baird
and 1 contributors


Maypole::Plugin::Trace - trace calls in Maypole


    use Maypole::Application qw/Trace/;
    # options:


Prints a trace of method entries and exits to STDERR.

Requires the latest version of Maypole in SVN, or 2.11 when it's released.


The default trace_level is set to 2.

The trace level must be set before calling setup.

    Level   Output
    0       none
    1       method entry and exit
    2       as above, but prints method arguments and return values
    3       uses Data::Dumper to expand method arguments and return values
                within Exported methods
    4       uses Data::Dumper to expand method arguments and return values 
                within all methods
    5       as 2, but also reports private methods (single leading _ in name)
    6       as 3, but also reports private methods (single leading _ in name)
    7       as 4, but also reports private methods (single leading _ in name)

Tracing is implemented for packages in the Maypole namespace, and in your application's namespace.

The characters E: are printed in the left margin to indicate when an exported method is being processed.

At trace level 2, objects, e.g. in class Foo, are represented as Foo(OBJECT). This is to avoid potential overloaded stringification, which causes deep recursion errors.

Note: trace output is only generated for exported methods when they are called via Maypole's own controller mechanism. So, for example, if a custom method directly calls an exported method, the entry to and exit from the exported method will not be registered in the trace output. This is a known bug, suggestions for how to fix it would be great.


Turn off tracing except within Exported methods. Default is 0 - trace all methods.

    # or
    __PACKAGE__->extra_trace_classes( [ 'Some::Problem::Package', 
                                        ] );

Adds the specified package(s) to the list of traced packages.


True or false, default false.

Shows the request path in trace output.

No path is shown for methods that do not include the Maypole request object in their parameters. This includes methods run before or after a request, most methods in non-Maypole packages, and some methods within the Maypole stack. Also, the path is not available until after parse_path() has returned.


Configures tracing.


David Baird, <>


Please report any bugs or feature requests to, or through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.



Copyright 2005 David Baird, All Rights Reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.