NAME

module-depakable - Check whether a module (or modules) is (are) depakable

VERSION

This document describes version 0.002 of module-depakable (from Perl distribution App-depakable), released on 2016-09-26.

SYNOPSIS

Usage:

% module-depakable [options] <modules> ...

Examples:

% module-depakable Data::Sah WWW::PAUSE::Simple
=head1 DESCRIPTION

This routine tries to determine whether the module(s) you specify, when use-d by a script, won't impair the ability to depak the script so that the script can run with requiring only core perl modules installed. The word "depak-able" (depak) comes from the name of the application that can pack a script using fatpack/datapack technique.

Let's start with the aforementioned goal: making a script run with only requiring core perl modules installed. This is a pretty reasonable goal for a common use-case: deploying a Perl application to a fresh perl installation. All the non-core modules that the script might use are packed along inside the script using fatpack (put inside a hash variable) or datapack (put in the DATA section) technique. But XS modules cannot be packed using this technique. And therefore, a module that requires non-core XS modules (either directly or indirectly) also cannot be used.

So in other words, this routine checks that a module is PP (pure-perl) and all of its (direct and indirect) dependencies are PP or core.

To check whether a module is PP/XS, Module::XSOrPP is used and this requires that the module is installed because Module::XSOrPP guesses by analyzing the module's source code.

To list all direct and indirect dependencies of a module, lcpan is used, so that application must be installed and run first to download and index a local CPAN/CPAN-like repository.

OPTIONS

* marks required options.

Configuration options

--config-path=filename

Set path to configuration file.

Can be specified multiple times.

--config-profile=s

Set configuration profile to use.

--no-config

Do not use any configuration file.

Environment options

--no-env

Do not read environment for default options.

Output options

--format=s

Choose output format, e.g. json, text.

Default value:

undef
--json

Set output format to json.

--naked-res

When outputing as JSON, strip result envelope.

Default value:

0

By default, when outputing as JSON, the full enveloped result is returned, e.g.:

[200,"OK",[1,2,3],{"func.extra"=>4}]

The reason is so you can get the status (1st element), status message (2nd element) as well as result metadata/extra result (4th element) instead of just the result (3rd element). However, sometimes you want just the result, e.g. when you want to pipe the result for more post-processing. In this case you can use `--naked-res` so you just get:

[1,2,3]

Other options

--help, -h, -?

Display help message and exit.

--modules-json=modulename

See --modules.

--modules=modulename*

Can be specified multiple times.

--version, -v

Display program's version and exit.

COMPLETION

This script has shell tab completion capability with support for several shells.

bash

To activate bash completion for this script, put:

complete -C module-depakable module-depakable

in your bash startup (e.g. ~/.bashrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is recommended, however, that you install shcompgen which allows you to activate completion scripts for several kinds of scripts on multiple shells. Some CPAN distributions (those that are built with Dist::Zilla::Plugin::GenShellCompletion) will even automatically enable shell completion for their included scripts (using shcompgen) at installation time, so you can immadiately have tab completion.

tcsh

To activate tcsh completion for this script, put:

complete module-depakable 'p/*/`module-depakable`/'

in your tcsh startup (e.g. ~/.tcshrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is also recommended to install shcompgen (see above).

other shells

For fish and zsh, install shcompgen as described above.

CONFIGURATION FILE

This script can read configuration files. Configuration files are in the format of IOD, which is basically INI with some extra features.

By default, these names are searched for configuration filenames (can be changed using --config-path): ~/.config/module-depakable.conf, ~/module-depakable.conf, or /etc/module-depakable.conf.

All found files will be read and merged.

To disable searching for configuration files, pass --no-config.

You can put multiple profiles in a single file by using section names like [profile=SOMENAME] or [SOMESECTION profile=SOMENAME]. Those sections will only be read if you specify the matching --config-profile SOMENAME.

You can also put configuration for multiple programs inside a single file, and use filter program=NAME in section names, e.g. [program=NAME ...] or [SOMESECTION program=NAME]. The section will then only be used when the reading program matches.

Finally, you can filter a section by environment variable using the filter env=CONDITION in section names. For example if you only want a section to be read if a certain environment variable is true: [env=SOMEVAR ...] or [SOMESECTION env=SOMEVAR ...]. If you only want a section to be read when the value of an environment variable has value equals something: [env=HOSTNAME=blink ...] or [SOMESECTION env=HOSTNAME=blink ...]. If you only want a section to be read when the value of an environment variable does not equal something: [env=HOSTNAME!=blink ...] or [SOMESECTION env=HOSTNAME!=blink ...]. If you only want a section to be read when an environment variable contains something: [env=HOSTNAME*=server ...] or [SOMESECTION env=HOSTNAME*=server ...]. Note that currently due to simplistic parsing, there must not be any whitespace in the value being compared because it marks the beginning of a new section filter or section name.

List of available configuration parameters:

format (see --format)
modules (see --modules)
naked_res (see --naked-res)

ENVIRONMENT

MODULE_DEPAKABLE_OPT => str

Specify additional command-line options

FILES

~/.config/module-depakable.conf

~/module-depakable.conf

/etc/module-depakable.conf

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/App-depakable.

SOURCE

Source repository is at https://github.com/perlancar/perl-App-depakable.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=App-depakable

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2016 by perlancar@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.