NAME

Shipwright::Manual::UsingFlags - Using Flags

DESCRIPTION

Shipwright flags is a method to make a single repository to support multiple variants of vessels.

Imagine you want to create a project which requires a database. There are several database types you want to support in the same repository, while you'd like each built vessel to only support one type. (Sometimes you have to choose one because some dists will be confused if provided with more than one type; e.g. for RT, you have to supply the database type when running ./configure).

This is a task that you can use Shipwright flags to accomplish.

For example, say you want to support both mysql and postgresql, and you've imported mysql, DBD::mysql, postgresql and DBD::Pg to the repository.

The next step is to mark dists with flags; let's use mysql and postgresql for this example.

$ shipwright flags -r ... mysql --set mysql
$ shipwright flags -r ... cpan-DBD-mysql --set mysql
$ shipwright flags -r ... postgresql --set postgresql
$ shipwright flags -r ... cpan-DBD-Pg --set postgresql
$ shipwright flags -r ... --mandatory --set mysql,postgresql db

Flags data is stored in shipwright/flags.yml

When building, you can then set --flags to mysql or postgresql to install support for that database only.

If a dist needs this info to configure (like RT for example), you'll need to customize the build script; see Shipwright::Manual::CustomizeBuild for information about how to do this.

If no flags are specified during build, both mysql and postgresql would be installed to the vessel. Which one RT chooses to configure for depends on its build script.

If necessary, you can also specify certain flags as being mandatory. For example, you can specify that a database flag is mandatory; if no flag labelled db is specified when invoking the build script, the first one is used as a default (mysql in this case) rather than the repository being built with no flags. This allows repositories to support different variants or versions of a program.

Note:

Shipwright will automatically add default to --flags, and if a dist has no flags set (i.e. it does not appear in shipwright/flags.yml), it will be given the default flag and will be installed by default.

SEE ALSO

Shipwright::Manual::CustomizeBuild

AUTHORS

sunnavy <sunnavy@bestpractical.com>

LICENCE AND COPYRIGHT

Shipwright is Copyright 2007-2010 Best Practical Solutions, LLC.

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