NAME

local::lib - create and use a local lib/ for perl modules with PERL5LIB

SYNOPSIS

In code -

use local::lib; # sets up a local lib at ~/perl5

use local::lib '~/foo'; # same, but ~/foo

# Or...
use FindBin;
use local::lib "$FindBin::Bin/../support";  # app-local support library

From the shell -

# Install LWP and it's missing dependencies to the 'my_lwp' directory
perl -MCPAN -Mlocal::lib=my_lwp -e 'CPAN::install(LWP)'

# Install LWP and *all non-core* dependencies to the 'my_lwp' directory 
perl -MCPAN -Mlocal::lib=--self-contained,my_lwp -e 'CPAN::install(LWP)'

# Just print out useful shell commands
$ perl -Mlocal::lib
export MODULEBUILDRC=/home/username/perl/.modulebuildrc
export PERL_MM_OPT='INSTALL_BASE=/home/username/perl'
export PERL5LIB='/home/username/perl/lib/perl5:/home/username/perl/lib/perl5/i386-linux'
export PATH="/home/username/perl/bin:$PATH"

To bootstrap if you don't have local::lib itself installed -

<download local::lib tarball from CPAN, unpack and cd into dir>

$ perl Makefile.PL --bootstrap
$ make test && make install

$ echo 'eval $(perl -I$HOME/perl5/lib/perl5 -Mlocal::lib)' >>~/.bashrc

# Or for C shells...

$ /bin/csh
% echo $SHELL
/bin/csh
% perl -I$HOME/perl5/lib/perl5 -Mlocal::lib >> ~/.cshrc

You can also pass --boostrap=~/foo to get a different location -

$ perl Makefile.PL --bootstrap=~/foo
$ make test && make install

$ echo 'eval $(perl -I$HOME/foo/lib/perl5 -Mlocal::lib=$HOME/foo)' >>~/.bashrc

If you want to install multiple Perl module environments, say for application evelopment, install local::lib globally and then:

$ cd ~/mydir1
$ perl -Mlocal::lib=./
$ eval $(perl -Mlocal::lib=./)  ### To set the environment for this shell alone
$ printenv  ### You will see that ~/mydir1 is in the PERL5LIB
$ perl -MCPAN -e install ...    ### whatever modules you want
$ cd ../mydir2
... REPEAT ...

For multiple environments for multiple apps you may need to include a modified version of the use FindBin instructions in the "In code" sample above. If you did something like the above, you have a set of Perl modules at ~/mydir1/lib. If you have a script at ~/mydir1/scripts/myscript.pl, you need to tell it where to find the modules you installed for it at ~/mydir1/lib>>.

In ~/mydir1/scripts/myscript.pl:

use strict;
use warnings;
use local::lib "$FindBin::Bin/..";  ### points to ~/mydir1 and local::lib finds lib
use lib "$FindBin::Bin/../lib";     ### points to ~/mydir1/lib

Put this before any BEGIN { ... } blocks that require the modules you installed.

DESCRIPTION

This module provides a quick, convenient way of bootstrapping a user-local Perl module library located within the user's home directory. It also constructs and prints out for the user the list of environment variables using the syntax appropriate for the user's current shell (as specified by the SHELL environment variable), suitable for directly adding to one's shell configuration file.

More generally, local::lib allows for the bootstrapping and usage of a directory containing Perl modules outside of Perl's @INC. This makes it easier to ship an application with an app-specific copy of a Perl module, or collection of modules. Useful in cases like when an upstream maintainer hasn't applied a patch to a module of theirs that you need for your application.

On import, local::lib sets the following environment variables to appropriate values:

MODULEBUILDRC

PERL_MM_OPT

PERL5LIB

PATH

PATH is appended to, rather than clobbered.

These values are then available for reference by any code after import.

METHODS

ensure_directory_structure_for

Arguments: path

Attempts to create the given path, and all required parent directories. Throws an exception on failure.

print_environment_vars_for

Arguments: path

Prints to standard output the variables listed above, properly set to use the given path as the base directory.

setup_env_hash_for

Arguments: path

Constructs the %ENV keys for the given path, by calling build_environment_vars_for.

install_base_perl_path

Arguments: path

Returns a path describing where to install the Perl modules for this local library installation. Appends the directories lib and perl5 to the given path.

install_base_arch_path

Arguments: path

Returns a path describing where to install the architecture-specific Perl modules for this local library installation. Based on the "install_base_perl_path" method's return value, and appends the value of $Config{archname}.

install_base_bin_path

Arguments: path

Returns a path describing where to install the executable programs for this local library installation. Based on the "install_base_perl_path" method's return value, and appends the directory bin.

modulebuildrc_path

Arguments: path

Returns a path describing where to install the .modulebuildrc file, based on the given path.

resolve_empty_path

Arguments: path

Builds and returns the base path into which to set up the local module installation. Defaults to ~/perl5.

resolve_home_path

Arguments: path

Attempts to find the user's home directory. If installed, uses File::HomeDir for this purpose. If no definite answer is available, throws an exception.

resolve_relative_path

Arguments: path

Translates the given path into an absolute path.

resolve_path

Arguments: path

Calls the following in a pipeline, passing the result from the previous to the next, in an attempt to find where to configure the environment for a local library installation: "resolve_empty_path", "resolve_home_path", "resolve_relative_path". Passes the given path argument to "resolve_empty_path" which then returns a result that is passed to "resolve_home_path", which then has its result passed to "resolve_relative_path". The result of this final call is returned from "resolve_path".

A WARNING ABOUT UNINST=1

Be careful about using local::lib in combination with "make install UNINST=1". The idea of this feature is that will uninstall an old version of a module before installing a new one. However it lacks a safety check that the old version and the new version will go in the same directory. Used in combination with local::lib, you can potentially delete a globally accessible version of a module while installing the new version in a local place. Only combine "make install UNINST=1" and local::lib if you understand these possible consequences.

LIMITATIONS

Rather basic shell detection. Right now anything with csh in its name is assumed to be a C shell or something compatible, and everything else is assumed to be Bourne. If the SHELL environment variable is not set, a Bourne-compatible shell is assumed.

Bootstrap is a hack and will use CPAN.pm for ExtUtils::MakeMaker even if you have CPANPLUS installed.

Kills any existing PERL5LIB, PERL_MM_OPT or MODULEBUILDRC.

Should probably auto-fixup CPAN config if not already done.

Patches very much welcome for any of the above.

ENVIRONMENT

SHELL

local::lib looks at the user's SHELL environment variable when printing out commands to add to the shell configuration file.

AUTHOR

Matt S Trout <mst@shadowcat.co.uk> http://www.shadowcat.co.uk/

auto_install fixes kindly sponsored by http://www.takkle.com/

CONTRIBUTORS

Patches to correctly output commands for csh style shells, as well as some documentation additions, contributed by Christopher Nehren <apeiron@cpan.org>.

'--self-contained' feature contributed by Mark Stosberg <mark@summersault.com>.

Doc patches for a custom local::lib patch contributed by Torsten Raudssus <torsten@raudssus.de>.

Hans Dieter Pearcey <hdp@cpan.org> sent in some additional tests for ensuring things will install properly.

LICENSE

This library is free software under the same license as perl itself

cpanm local::lib

perl -MCPAN -e shell
install local::lib