File::ShareDir::ProjectDistDir(3)

NAME
File::ShareDir::ProjectDistDir - Simple set-and-forget using of a '/share' directory in your projects root

VERSION
version 0.5.2

SYNOPSIS
  package An::Example::Package;

  use File::ShareDir::ProjectDistDir;

  # during development, $dir will be $projectroot/share
  # but once installed, it will be wherever File::Sharedir thinks it is.
  my $dir = dist_dir('An-Example')

Project layout requirements:

  $project/
  $project/lib/An/Example/Package.pm
  $project/share/   # files for package 'An-Example' go here.

You can use a directory name other than 'share' ( Assuming you make sure when you install that, you specify the different directory there also ) as follows:

  use File::ShareDir::ProjectDistDir ':all', defaults => {
    projectdir => 'templates',
  };

METHODS

  import
    use File::ShareDir::ProjectDistDir (@args);

This uses "Sub::Exporter" to do the heavy lifting, so most usage of this module can be maximised by understanding that first.

•   ":all"

        ->import( ':all' , .... )

    Import both "dist_dir" and "dist_file"

•   "dist_dir"

        ->import('dist_dir' , .... )

    Import the dist_dir method

•   "dist_dir"

        ->import('dist_file' , .... )

    Import the dist_file method

•   "projectdir"

        ->import( .... , projectdir => 'share' )

    Specify what the project directory is as a path relative to the base of your distributions source, and this directory will be used as a "ShareDir" simulation path for the exported methods During development.

    If not specified, the default value 'share' is used.

•   "filename"

        ->import( .... , filename => 'some/path/to/foo.pm' );

    Generally you don't want to set this, as its worked out by caller() to work out the name of the file its being called from. This file's path is walked up to find the 'lib' element with a sibling of the name of your "projectdir".

•   "distname"

        ->import( .... , distname => 'somedistname' );

    Specifying this argument changes the way the functions are emitted at installed "runtime", so that instead of taking the standard arguments File::ShareDir does, the specification of the "distname" in those functions is eliminated.

    i.e:

        # without this flag
        use File::ShareDir::ProjectDistDir qw( :all );

        my $dir = dist_dir('example');
        my $file = dist_file('example', 'path/to/file.pm' );

        # with this flag
        use File::ShareDir::ProjectDistDir ( qw( :all ), distname => 'example' );

        my $dir = dist_dir();
        my $file = dist_file('path/to/file.pm' );

•   "defaults"

        ->import( ... , defaults => {
            filename => ....,
            projectdir => ....,
        });

    This is mostly an alternative syntax for specifying "filename" and "projectdir", which is mostly used internally, and their corresponding other values are packed into this one.

Sub::Exporter tricks of note.

Make your own sharedir util

    package Foo::Util;

    sub import {
        my ($caller_class, $caller_file, $caller_line )  = caller();
        if ( grep { /share/ } @_ ) {
            require File::ShareDir::ProjectDistDir;
            File::ShareDir::ProjectDistDir->import(
                filename => $caller_file,
                dist_dir => { distname => 'myproject' , -as => 'share' },
                dist_dir => { distname => 'otherproject' , -as => 'other_share' , projectdir => 'share2' },
                -into => $caller_class,
            );
        }
    }

    ....

    package Foo;
    use Foo::Util qw( share );

    my $dir = share();
    my $other_dir => other_share();

  build_dist_dir
    use File::ShareDir::ProjectDirDir ( : all );

    #  this calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_dir(
      'dist_dir' => {},
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } }
    );

    use File::ShareDir::ProjectDirDir ( qw( :all ), distname => 'example-dist' );

    #  this calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_dir(
      'dist_dir' => {},
      { distname => 'example-dist', defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } }
    );

    use File::ShareDir::ProjectDirDir
      dist_dir => { distname => 'example-dist', -as => 'mydistdir' },
      dist_dir => { distname => 'other-dist',   -as => 'otherdistdir' };

    # This calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_dir(
      'dist_dir',
      { distname => 'example-dist' },
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } },
    );
    my $othercoderef = File::ShareDir::ProjectDistDir->build_dist_dir(
      'dist_dir',
      { distname => 'other-dist' },
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } },
    );

    # And leverages Sub::Exporter to create 2 subs in your package.

Generates the exported 'dist_dir' method. In development environments, the generated method will return a path to the development directories 'share' directory. In non-development environments, this simply returns "File::ShareDir::dist_dir".

As a result of this, specifying the Distribution name is not required during development, however, it will start to matter once it is installed. This is a potential avenues for bugs if you happen to name it wrong.

  build_dist_file
    use File::ShareDir::ProjectDirDir ( : all );

    #  this calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_file(
      'dist_file' => {},
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } }
    );

    use File::ShareDir::ProjectDirDir ( qw( :all ), distname => 'example-dist' );

    #  this calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_file(
      'dist_file' => {},
      { distname => 'example-dist', defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } }
    );

    use File::ShareDir::ProjectDirDir
      dist_file => { distname => 'example-dist', -as => 'mydistfile' },
      dist_file => { distname => 'other-dist',   -as => 'otherdistfile' };

    # This calls
    my $coderef = File::ShareDir::ProjectDistDir->build_dist_file(
      'dist_file',
      { distname => 'example-dist' },
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } },
    );
    my $othercoderef = File::ShareDir::ProjectDistDir->build_dist_file(
      'dist_file',
      { distname => 'other-dist' },
      { defaults => { filename => 'path/to/yourcallingfile.pm', projectdir => 'share' } },
    );

    # And leverages Sub::Exporter to create 2 subs in your package.

Generates the 'dist_file' method.

In development environments, the generated method will return a path to the development directories 'share' directory. In non-development environments, this simply returns "File::ShareDir::dist_file".

Caveats as a result of package-name as stated in "build_dist_dir" also apply to this method.

SIGNIFICANT CHANGES

  0.5.0 - Heuristics and Return type changes
New "devdir" heuristic

Starting with 0.5.0, instead of using our simple "lib/../share" pattern heuristic, a more advanced heuristic is used from the new "Path::FindDev" and "Path::IsDev".

This relies on a more "concrete" marker somewhere at the top of your development tree, and more importantly, checks for the existence of specific files that are not likely to occur outside a project root.

"lib" and "share" based heuristics were a little fragile, for a few reasons:

•   "lib" can, and does appear all over UNIX file systems, for purposes other than development project roots.

    For instance, have a look in "/usr/"

        /usr/bin
        /usr/lib
        /usr/share  ## UHOH.

    This would have the very bad side effect of anything installed in "/usr/lib" thinking its "in development".

    Fortunately, nobody seems to have hit this specific bug, which I suspect is due only to "/usr/lib" being a symbolic link on most x86_64 systems.

•   "lib" is also reasonably common within "CPAN" package names.

    For instance:

        lib::abs

    Which means you'll have a hierarchy like:

        $PREFIX/lib/lib/abs

    All you need for something to go horribly wrong would be for somebody to install a "CPAN" module named:

        share::mystuff

    Or similar, and instantly, you have:

        $PREFIX/lib/lib/
        $PREFIX/lib/share/

    Which would mean any module calling itself "lib::*" would be unable to use this module.

So instead, as of 0.5.0, the heuristic revolves around certain specific files being in the "dev" directory.

Which is hopefully a more fault resilient mechanism.

New Return Types

Starting with 0.5.0, the internals are now based on "Path::Tiny" instead of "Path::Class", and as a result, there may be a few glitches in transition.

Also, previously you could get a "Path::Class::*" object back from "dist_dir" and "dist_file" by importing it as such:

    use File::ShareDir::ProjectDistDir
        qw( dist_dir dist_file ),
        defaults => { pathclass => 1 };

Now you can also get "Path::Tiny" objects back, by passing:

    use File::ShareDir::ProjectDistDir
        qw( dist_dir dist_file ),
        defaults => { pathtiny => 1 };

For the time being, you can still get Path::Class objects back, but its likely to be deprecated in future.

( In fact, I may even make 2 specific sub-classes of "PDD" for people who want objects back, as it will make the "API" and the code much cleaner )

AUTHOR
Kent Fredric <kentnl@cpan.org>

COPYRIGHT AND LICENSE
This software is copyright (c) 2013 by Kent Fredric <kentnl@cpan.org>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.