NAME
    CatalystX::DebugFilter - Provides configurable filtering of data that is
    logged to the debug logs (and error screen)

VERSION
    version 0.10

SYNOPSIS
        package MyApp;

        use Catalyst;
        with 'CatalystX::DebugFilter';

        __PACKAGE__->config(
            'CatalystX::DebugFilter' => {

                # filter all "Cookie" headers as well as "password" and "SECRET" parameters
                Request => { headers => 'Cookie', params => [ 'password', qr/SECRET/ ] },

                # filter all Set-Cookie values in the response
                Response => { headers => 'Set-Cookie' },

                Stash => [
                    sub {
                        my ( $key, $value ) = @_;
                        my $type = ref($value);

                        # ignore any non-ref values
                        return undef if !$type;

                        if ( $type->isa('DBIx::Class::ResultSet') ) {    # dump ResultSet objects as SQL
                            return $value->as_query;
                        } elsif ( $type->isa('DBIx::Class::Result') ) {    # dump Result objects as simple HASH
                            return { $value->get_columns };
                        } else {                                           # ignore these
                            return undef;
                        }
                    },
                ],
                Session => [
                    'secret_session_key'
                ],
            }
        );

DESCRIPTION
    This module provides a Moose role that will filter certain elements of a
    request/response/stash/session before they are logged to the debug logs
    (or the error screen).

METHODS
  dump_these
    This role uses an "around" method modifier on the "dump_these" in
    Catalyst method and modifies the elements returned according to the
    configuration provided by the user as demonstrated in the SYNOPSIS
    section.

FILTER CONFIGURATION
    There are few different types of filters that can be defined:

    *   Exact Match

        The parameter/header/stash key is compared against a literal string.
        If it matches, the value is replaced with "[FILTERED]"

    *   Regular Expression

        The parameter/header/stash key is compared against a regular
        expression. If it matches, the value is replaced with "[FILTERED]"

    *   Callback

        The parameter/header/stash key and value are passed to a callback
        function. If the function returns a defined value, that value is
        used instead of the original value.

    This module supports filtering a few different types of data (naturally,
    these could all be combined into a single "config" call):

    *   Request Parameters

            __PACKAGE__->config( 'CatalystX::DebugFilter' => { Request => { params => $filters } } );

    *   Request Headers

        Useful with CatalystX::Debug::RequestHeaders:

            __PACKAGE__->config( 'CatalystX::DebugFilter' => { Request => { headers => $filters } } );

    *   Response Headers

        Useful with CatalystX::Debug::ResponseHeaders:

            __PACKAGE__->config( 'CatalystX::DebugFilter' => { Response => { headers => $filters } } );

    *   Stash Data

            __PACKAGE__->config( 'CatalystX::DebugFilter' => { Stash => $filters } );

    In each of the above examples, $filters can be one of a few things:

    *   A non-ref scalar, implying an exact match

    *   A Regexp reference, implying an regular expression match

    *   A CODE reference, implying a callback matching function

    *   An ARRAY reference of any of the above

CAVEATS
    This module will not magically remove all references to a specific piece
    of data unless filters are explicitly defined for each place this data
    is stored. For instance, you may define a request parameter filter to
    prevent passwords from being logged to the debug logs but if you create
    an object that contains that password and store it in the stash, the
    password value may still appear on the error screen.

    Also, the stash and session are only filtered at the top level. If you
    would like to filter more extensively, you can use a filter callback to
    traverse the hash, modifying whatever data you like (a shallow copy is
    made before passing the value to the callback).

SEE ALSO
    *   CatalystX::Debug::RequestHeaders

    *   CatalystX::Debug::ResponseHeaders

AUTHOR
    Brian Phillips <bphillips@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2012 by Brian Phillips.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.