Provided by: libdbix-class-schema-loader-perl_0.07048-1_all 
NAME
$class - Optional module dependency specifications (for module authors) EOC
#@@ #@@ SYNOPSIS HEADING #@@
push @chunks, <<"EOC"; =head1 SYNOPSIS
Somewhere in your build-file (e.g. ExtUtils::MakeMaker's Makefile.PL):
...
\$EUMM_ARGS{CONFIGURE_REQUIRES} = {
\%{ \$EUMM_ARGS{CONFIGURE_REQUIRES} || {} },
'DBIx::Class::Schema::Loader' => '$distver',
};
...
my %DBIC_CONFIG_AND_ORACLE_DEPS = %{ eval {
require $class;
$class->req_list_for([qw( dbicdump_config rdbms_oracle )]);
} || {} };
\$EUMM_ARGS{PREREQ_PM} = {
\%DBIC_CONFIG_AND_ORACLE_DEPS,
\%{ \$EUMM_ARGS{PREREQ_PM} || {} },
};
...
ExtUtils::MakeMaker::WriteMakefile(\%EUMM_ARGS);
Note: The "eval" protection within the example is due to support for requirements during the "configure"
build phase not being available on a sufficient portion of production installations of Perl. Robust
support for such dependency requirements is available in the CPAN installer only since version "1.94_56"
first made available for production with perl version 5.12. It is the belief of the current maintainer
that support for requirements during the "configure" build phase will not be sufficiently ubiquitous
until the year 2020 at the earliest, hence the extra care demonstrated above. It should also be noted
that some 3rd party installers (e.g. cpanminus) do the right thing with configure requirements
independent from the versions of perl and CPAN available. EOC
#@@ #@@ DESCRIPTION HEADING #@@
push @chunks, <<'EOC'; =head1 DESCRIPTION
Some of the less-frequently used features of DBIx::Class::Schema::Loader have external module
dependencies on their own. In order not to burden the average user with modules they will never use,
these optional dependencies are not included in the base Makefile.PL. Instead an exception with a
descriptive message is thrown when a specific feature can't find one or several modules required for its
operation. This module is the central holding place for the current list of such dependencies, for
DBIx::Class::Schema::Loader core authors, and DBIx::Class::Schema::Loader extension authors alike.
Dependencies are organized in groups where each group can list one or more required modules, with an
optional minimum version (or 0 for any version). In addition groups prefixed with "test_" can specify a
set of environment variables, some (or all) of which are marked as required for the group to be
considered by "req_list_for"
Each group name (or a combination thereof) can be used in the public methods as described below. EOC
#@@ #@@ REQUIREMENT GROUPLIST HEADING #@@
push @chunks, '=head1 CURRENT REQUIREMENT GROUPS';
my $standalone_info;
for my $group (sort keys %$dbic_reqs) {
my $info = $standalone_info->{$group} ||= $class->_groups_to_reqs($group);
next unless (
$info->{modreqs_fully_documented}
and
( $info->{augments} or $info->{modreqs} )
);
my $p = $dbic_reqs->{$group}{pod};
push @chunks, (
"=head2 $p->{title}",
"=head3 $group",
$p->{desc},
'=over',
);
if ( keys %{ $info->{modreqs}||{} } ) {
push @chunks, map
{ "=item * $_" . ($info->{modreqs}{$_} ? " >= $info->{modreqs}{$_}" : '') }
( sort keys %{ $info->{modreqs} } )
;
}
else {
push @chunks, '=item * No standalone requirements',
}
push @chunks, '=back';
for my $ag ( sort keys %{ $info->{augments} || {} } ) {
my $ag_info = $standalone_info->{$ag} ||= $class->_groups_to_reqs($ag);
my $newreqs = $class->modreq_list_for([ $group, $ag ]);
for (keys %$newreqs) {
delete $newreqs->{$_} if (
( defined $info->{modreqs}{$_} and $info->{modreqs}{$_} == $newreqs->{$_} )
or
( defined $ag_info->{modreqs}{$_} and $ag_info->{modreqs}{$_} == $newreqs->{$_} )
);
}
if (keys %$newreqs) {
push @chunks, (
"Combined with L</$ag> additionally requires:",
'=over',
( map
{ "=item * $_" . ($newreqs->{$_} ? " >= $newreqs->{$_}" : '') }
( sort keys %$newreqs )
),
'=back',
);
}
}
}
#@@ #@@ API DOCUMENTATION HEADING #@@
push @chunks, <<'EOC';
IMPORT-LIKE ACTIONS
Even though this module is not an Exporter, it recognizes several "actions" supplied to its "import"
method.
-skip_all_without
Arguments: @group_names
A convenience wrapper for use during testing: EOC
push @chunks, " use $class -skip_all_without => qw(admin test_rdbms_mysql);";
push @chunks, 'Roughly equivalent to the following code:';
push @chunks, sprintf <<'EOS', ($class) x 2;
BEGIN {
require %s;
if ( my $missing = %s->req_missing_for(\@group_names_) ) {
print "1..0 # SKIP requirements not satisfied: $missing\n";
exit 0;
}
}
EOS
push @chunks, <<'EOC';
It also takes into account the "RELEASE_TESTING" environment variable and behaves like "-die_without" for
any requirement groups marked as "release_testing_mandatory".
-die_without
Arguments: @group_names
A convenience wrapper around "die_unless_req_ok_for": EOC
push @chunks, " use $class -die_without => qw(deploy admin);";
push @chunks, <<'EOC';
-list_missing
Arguments: @group_names
A convenience wrapper around "modreq_missing_for":
perl -Ilib -MDBIx::Class::Schema::Loader::Optional::Dependencies=-list_missing,dbicdump_config,rdbms_oracle | cpanm
METHODS
req_group_list
Arguments: none
Return Value: \%list_of_requirement_groups
This method should be used by DBIx::Class::Schema::Loader packagers, to get a hashref of all dependencies
keyed by dependency group. Each key (group name), or a combination thereof (as an arrayref) can be
supplied to the methods below. The values of the returned hash are currently a set of options without a
well defined structure. If you have use for any of the contents - contact the maintainers, instead of
treating this as public (left alone stable) API.
req_list_for
Arguments: $group_name | \@group_names
Return Value: \%set_of_module_version_pairs
This method should be used by DBIx::Class::Schema::Loader extension authors, to determine the version of
modules a specific set of features requires for this version of DBIx::Class::Schema::Loader (regardless
of their availability on the system). See the "SYNOPSIS" for a real-world example.
When handling "test_*" groups this method behaves differently from "modreq_list_for" below (and is the
only such inconsistency among the "req_*" methods). If a particular group declares as requirements some
"environment variables" and these requirements are not satisfied (the envvars are unset) - then the
"module requirements" of this group are not included in the returned list.
modreq_list_for
Arguments: $group_name | \@group_names
Return Value: \%set_of_module_version_pairs
Same as "req_list_for" but does not take into consideration any "environment variable requirements" -
returns just the list of required modules.
req_ok_for
Arguments: $group_name | \@group_names
Return Value: 1|0
Returns true or false depending on whether all modules/envvars required by the group(s) are loadable/set
on the system.
req_missing_for
Arguments: $group_name | \@group_names
Return Value: $error_message_string
Returns a single-line string suitable for inclusion in larger error messages. This method would normally
be used by DBIx::Class::Schema::Loader core features, to indicate to the user that they need to install
specific modules and/or set specific environment variables before being able to use a specific feature
set.
For example if some of the requirements for "deploy" are not available, the returned string could look
like: EOC
push @chunks, qq{ "Moose~$moosever" (see $class documentation for details)};
push @chunks, <<'EOC';
The author is expected to prepend the necessary text to this message before
returning the actual error seen by the user. See also L</modreq_missing_for>
modreq_missing_for
Arguments: $group_name | \@group_names
Return Value: $error_message_string
Same as "req_missing_for" except that the error string is guaranteed to be either empty, or contain a set
of module requirement specifications suitable for piping to e.g. cpanminus. The method explicitly does
not attempt to validate the state of required environment variables (if any).
For instance if some of the requirements for "deploy" are not available, the returned string could look
like: EOC
push @chunks, qq{ "Moose~$moosever"};
push @chunks, <<'EOC';
See also "-list_missing".
skip_without
Arguments: $group_name | \@group_names
A convenience wrapper around skip. It does not take neither a reason (it is generated by
"req_missing_for") nor an amount of skipped tests (it is always 1, thus mandating unconditional use of
done_testing). Most useful in combination with ad hoc requirement specifications: EOC
push @chunks, <<EOC;
SKIP: {
$class->skip_without([ deploy YAML>=0.90 ]);
...
}
EOC
push @chunks, <<'EOC';
die_unless_req_ok_for
Arguments: $group_name | \@group_names
Checks if "req_ok_for" passes for the supplied group(s), and in case of failure throws an exception
including the information from "req_missing_for". See also "-die_without".
modreq_errorlist_for
Arguments: $group_name | \@group_names
Return Value: \%set_of_loaderrors_per_module
Returns a hashref containing the actual errors that occurred while attempting to load each module in the
requirement group(s).
req_errorlist_for
Deprecated method name, equivalent (via proxy) to "modreq_errorlist_for".
EOC
#@@ #@@ FOOTER #@@
push @chunks, <<'EOC'; =head1 FURTHER QUESTIONS?
Check the list of additional DBIC resources.
COPYRIGHT AND LICENSE
This module is free software copyright by the DBIx::Class::Schema::Loader (DBICSL) authors. You can
redistribute it and/or modify it under the same terms as the DBIx::Class::Schema::Loader library. EOC
eval {
open (my $fh, '>', $podfn) or die;
print $fh join ("\n\n", @chunks) or die;
print $fh "\n" or die;
close ($fh) or die;
} or croak( "Unable to write $podfn: " . ( $! || $@ || 'unknown error') );
}
1;
perl v5.26.1 2018-DBIx::Class::Schema::Loader::Optional::Dependencies(3pm)