config_data (1) - Linux Man Pages
config_data: Query or change configuration of Perl modules
config_data - Query or change configuration of Perl modules
# Get config/feature values config_data --module Foo::Bar --feature bazzable config_data --module Foo::Bar --config magic_number # Set config/feature values config_data --module Foo::Bar --set_feature bazzable=1 config_data --module Foo::Bar --set_config magic_number=42 # Print a usage message config_data --help
DESCRIPTIONThe "config_data" tool provides a command-line interface to the configuration of Perl modules. By ``configuration'', we mean something akin to ``user preferences'' or ``local settings''. This is a formalization and abstraction of the systems that people like Andreas Koenig ("CPAN::Config"), Jon Swartz ("HTML::Mason::Config"), Andy Wardley ("Template::Config"), and Larry Wall (perl's own Config.pm) have developed independently.
The configuration system employed here was developed in the context of "Module::Build". Under this system, configuration information for a module "Foo", for example, is stored in a module called "Foo::ConfigData") (I would have called it "Foo::Config", but that was taken by all those other systems mentioned in the previous paragraph...). These "...::ConfigData" modules contain the configuration data, as well as publicly accessible methods for querying and setting (yes, actually re-writing) the configuration data. The "config_data" script (whose docs you are currently reading) is merely a front-end for those methods. If you wish, you may create alternate front-ends.
The two types of data that may be stored are called "config" values and "feature" values. A "config" value may be any perl scalar, including references to complex data structures. It must, however, be serializable using "Data::Dumper". A "feature" is a boolean (1 or 0) value.
USAGEThis script functions as a basic getter/setter wrapper around the configuration of a single module. On the command line, specify which module's configuration you're interested in, and pass options to get or set "config" or "feature" values. The following options are supported:
- Specifies the name of the module to configure (required).
- When passed the name of a "feature", shows its value. The value will be 1 if the feature is enabled, 0 if the feature is not enabled, or empty if the feature is unknown. When no feature name is supplied, the names and values of all known features will be shown.
- When passed the name of a "config" entry, shows its value. The value will be displayed using "Data::Dumper" (or similar) as perl code. When no config name is supplied, the names and values of all known config entries will be shown.
- Sets the given "feature" to the given boolean value. Specify the value as either 1 or 0.
- Sets the given "config" entry to the given value.
- If the "--eval" option is used, the values in "set_config" will be evaluated as perl code before being stored. This allows moderately complicated data structures to be stored. For really complicated structures, you probably shouldn't use this command-line interface, just use the Perl API instead.
- Prints a help message, including a few examples, and exits.