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Edit File: config_data
#!/usr/bin/perl use strict; use Module::Build 0.25; use Getopt::Long; my %opt_defs = ( module => {type => '=s', desc => 'The name of the module to configure (required)'}, feature => {type => ':s', desc => 'Print the value of a feature or all features'}, config => {type => ':s', desc => 'Print the value of a config option'}, set_feature => {type => '=s%', desc => "Set a feature to 'true' or 'false'"}, set_config => {type => '=s%', desc => 'Set a config option to the given value'}, eval => {type => '', desc => 'eval() config values before setting'}, help => {type => '', desc => 'Print a help message and exit'}, ); my %opts; GetOptions( \%opts, map "$_$opt_defs{$_}{type}", keys %opt_defs ) or die usage(%opt_defs); print usage(%opt_defs) and exit(0) if $opts{help}; my @exclusive = qw(feature config set_feature set_config); die "Exactly one of the options '" . join("', '", @exclusive) . "' must be specified\n" . usage(%opt_defs) unless grep(exists $opts{$_}, @exclusive) == 1; die "Option --module is required\n" . usage(%opt_defs) unless $opts{module}; my $cf = load_config($opts{module}); if (exists $opts{feature}) { if (length $opts{feature}) { print $cf->feature($opts{feature}); } else { my %auto; # note: need to support older ConfigData.pm's @auto{$cf->auto_feature_names} = () if $cf->can("auto_feature_names"); print " Features defined in $cf:\n"; foreach my $name (sort $cf->feature_names) { print " $name => ", $cf->feature($name), (exists $auto{$name} ? " (dynamic)" : ""), "\n"; } } } elsif (exists $opts{config}) { require Data::Dumper; local $Data::Dumper::Terse = 1; if (length $opts{config}) { print Data::Dumper::Dumper($cf->config($opts{config})), "\n"; } else { print " Configuration defined in $cf:\n"; foreach my $name (sort $cf->config_names) { print " $name => ", Data::Dumper::Dumper($cf->config($name)), "\n"; } } } elsif (exists $opts{set_feature}) { my %to_set = %{$opts{set_feature}}; while (my ($k, $v) = each %to_set) { die "Feature value must be 0 or 1\n" unless $v =~ /^[01]$/; $cf->set_feature($k, 0+$v); # Cast to a number, not a string } $cf->write; print "Feature" . 's'x(keys(%to_set)>1) . " saved\n"; } elsif (exists $opts{set_config}) { my %to_set = %{$opts{set_config}}; while (my ($k, $v) = each %to_set) { if ($opts{eval}) { $v = eval($v); die $@ if $@; } $cf->set_config($k, $v); } $cf->write; print "Config value" . 's'x(keys(%to_set)>1) . " saved\n"; } sub load_config { my $mod = shift; $mod =~ /^([\w:]+)$/ or die "Invalid module name '$mod'"; my $cf = $mod . "::ConfigData"; eval "require $cf"; die $@ if $@; return $cf; } sub usage { my %defs = @_; my $out = "\nUsage: $0 [options]\n\n Options include:\n"; foreach my $name (sort keys %defs) { $out .= " --$name"; for ($defs{$name}{type}) { /^=s$/ and $out .= " <string>"; /^=s%$/ and $out .= " <string>=<value>"; } pad_line($out, 35); $out .= "$defs{$name}{desc}\n"; } $out .= <<EOF; Examples: $0 --module Foo::Bar --feature bazzable $0 --module Foo::Bar --config magic_number $0 --module Foo::Bar --set_feature bazzable=1 $0 --module Foo::Bar --set_config magic_number=42 EOF return $out; } sub pad_line { $_[0] .= ' ' x ($_[1] - length($_[0]) + rindex($_[0], "\n")) } __END__ =head1 NAME config_data - Query or change configuration of Perl modules =head1 SYNOPSIS # 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 =head1 DESCRIPTION The C<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 (C<CPAN::Config>), Jon Swartz (C<HTML::Mason::Config>), Andy Wardley (C<Template::Config>), and Larry Wall (perl's own Config.pm) have developed independently. The configuration system employed here was developed in the context of C<Module::Build>. Under this system, configuration information for a module C<Foo>, for example, is stored in a module called C<Foo::ConfigData>) (I would have called it C<Foo::Config>, but that was taken by all those other systems mentioned in the previous paragraph...). These C<...::ConfigData> modules contain the configuration data, as well as publicly accessible methods for querying and setting (yes, actually re-writing) the configuration data. The C<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 C<config> values and C<feature> values. A C<config> value may be any perl scalar, including references to complex data structures. It must, however, be serializable using C<Data::Dumper>. A C<feature> is a boolean (1 or 0) value. =head1 USAGE This 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 C<config> or C<feature> values. The following options are supported: =over 4 =item module Specifies the name of the module to configure (required). =item feature When passed the name of a C<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. =item config When passed the name of a C<config> entry, shows its value. The value will be displayed using C<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. =item set_feature Sets the given C<feature> to the given boolean value. Specify the value as either 1 or 0. =item set_config Sets the given C<config> entry to the given value. =item eval If the C<--eval> option is used, the values in C<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. =item help Prints a help message, including a few examples, and exits. =back =head1 AUTHOR Ken Williams, kwilliams@cpan.org =head1 COPYRIGHT Copyright (c) 1999, Ken Williams. All rights reserved. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =head1 SEE ALSO Module::Build(3), perl(1). =cut