NAME

DBD::Sys::Plugin - embed own tables to DBD::Sys

DESCRIPTION

DBD::Sys is developed to use a unique, well known interface (SQL) to access data from underlying system which is available in tabular context (or easily could transformed into).

The major goal of DBD::Sys is the ability to have an interface to collect relevant data to operate a system - regardless the individual type. Therefore it uses plugins to provide the accessible tables and can be extended by adding plugins.

Plugin structure

Each plugin must be named DBD::Sys::Plugin::Plugin-Name. This package can provide an external callable method named getSupportedTables which must return a hash containing the provided tables as key and the classes which implement the tables as associated value, e.g.:

  package DBD::Sys::Plugin::Foo;

  use base qw(DBD::Sys::Plugin);

  sub getSupportedTables()
  {
      (
          mytable => 'DBD::Sys::Plugin::Foo::MyTable';
      )
  }

If the table is located in additional module, it must be required either by the plugin package on loading or at least when it's returned by getSupportedTables.

If this method is not provided, the namespace below the plugin name will be scanned for tables using Module::Pluggable::Object:

  sub DBD::Sys::Plugin::getSupportedTables
  {
      my $proto = blessed($_[0]) || $_[0];
      my $finder = Module::Pluggable::Object->new(
                                                   require     => 1,
                                                   search_path => [$proto],
                                                   inner       => 0,
      );
      my @tableClasses = $finder->plugins();
      ...
  }

It's strongly recommended to derive the table classes from DBD::Sys::Table, but it's required that it is a SQL::Eval::Table and provides the getColNames and collectData methods:

  package DBD::Sys::Plugin::Foo::MyTable;

  use base qw(DBD::Sys::Table);

  sub getColNames() { qw(col1 col2 col3) }

  sub collectData()
  {
      # ...

      return \@data;
  }