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NAME

datapack-modules - Like Module::FatPack, but uses datapacking instead of fatpack

VERSION

This document describes version 0.06 of datapack-modules (from Perl distribution App-DataPackUtils), released on 2020-04-30.

SYNOPSIS

Usage:

% datapack-modules [--config-path=path | -c] [--config-profile=profile |
    -P] [--format=name] [--json] [-m=s+] [--module-name=s+]
    [--module-names-json=s] [--module-src key=s] [--module-srcs-json=s]
    [--(no)naked-res] [--no-config | -C] [--no-env] [--no-overwrite]
    [--no-stripper] [--no-stripper-comment] [--no-stripper-log]
    [--no-stripper-maintain-linum] [--no-stripper-pod] [--no-stripper-ws]
    [--nooverwrite] [--nostripper] [--nostripper-comment]
    [--nostripper-log] [--nostripper-maintain-linum] [--nostripper-pod]
    [--nostripper-ws] [-o=s] [--output=s] [--overwrite]
    [--page-result[=program]] [--postamble=s] [--preamble=s]
    [--put-hook-at-the-end] [--stripper] [--stripper-comment]
    [--stripper-log] [--stripper-maintain-linum] [--stripper-pod]
    [--stripper-ws] [module_name] ...

Examples:

Datapack two modules:

% datapack-modules Text::Table::Tiny Try::Tiny

DESCRIPTION

Both this module and Module:FatPack generate source code that embeds modules' source codes and load them on-demand via require hook. The difference is that the modules' source codes are put in __DATA__ section instead of regular Perl hashes (fatpack uses %fatpacked). This reduces compilation overhead, although this is not noticeable unless when the number of embedded modules is quite large. For example, in App::pause, the pause script embeds ~320 modules with a total of ~54000 lines. The overhead of fatpack code is ~49ms on my PC, while with datapack the overhead is about ~10ms.

There are two downsides of this technique. The major one is that you cannot load modules during BEGIN phase (e.g. using use) because at that point, DATA section is not yet available. You can only use run-time require()'s.

Another downside of this technique is that you cannot use __DATA__ section for other purposes (well, actually with some care, you still can).

OPTIONS

* marks required options.

Main options

--put-hook-at-the-end

Put the require hook at the end of @INC using "push" instead of at the front using "unshift".

Configuration options

--config-path=s, -c

Set path to configuration file.

--config-profile=s, -P

Set configuration profile to use.

--no-config, -C

Do not use any configuration file.

Environment options

--no-env

Do not read environment for default options.

Input options

--module-name=modulename, -m

Module names to search.

Can be specified multiple times.

--module-names-json=modulename

Module names to search (JSON-encoded).

See --module-name.

--module-src=s%

Module source codes (a hash, keys are module names).

Each value is a name-value pair, use key=value syntax. Can be specified multiple times.

--module-srcs-json=s

Module source codes (a hash, keys are module names) (JSON-encoded).

See --module-src.

--postamble=s

Perl source code to add after the datapack code (but before the __DATA__ section).

--preamble=s

Perl source code to add before the datapack code.

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]
--output=filename, -o

Output filename.

--overwrite

Overwrite output if previously exists.

--page-result

Filter output through a pager.

Stripping options

--no-stripper-comment

Set strip_comment=0 (don't strip comments) in Perl::Stripper.

--no-stripper-pod

Set strip_pod=0 (don't strip POD) in Perl::Stripper.

--no-stripper-ws

Set strip_ws=0 (don't strip whitespace) in Perl::Stripper.

--stripper

Strip included modules using Perl::Stripper.

--stripper-log

Set strip_log=1 (strip log statements) in Perl::Stripper.

--stripper-maintain-linum

Set maintain_linum=1 in Perl::Stripper.

Other options

--help, -h, -?

Display help message and exit.

--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 datapack-modules datapack-modules

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 modules using cpanm-shcompgen which can activate shell completion for scripts immediately.

tcsh

To activate tcsh completion for this script, put:

complete datapack-modules 'p/*/`datapack-modules`/'

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/datapack-modules.conf, ~/datapack-modules.conf, or /etc/datapack-modules.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)
module_names (see --module-name)
module_srcs (see --module-src)
naked_res (see --naked-res)
output (see --output)
overwrite (see --overwrite)
postamble (see --postamble)
preamble (see --preamble)
put_hook_at_the_end (see --put-hook-at-the-end)
stripper (see --stripper)
stripper_comment (see --no-stripper-comment)
stripper_log (see --stripper-log)
stripper_maintain_linum (see --stripper-maintain-linum)
stripper_pod (see --no-stripper-pod)
stripper_ws (see --no-stripper-ws)

ENVIRONMENT

DATAPACK_MODULES_OPT => str

Specify additional command-line options.

FILES

~/.config/datapack-modules.conf

~/datapack-modules.conf

/etc/datapack-modules.conf

HOMEPAGE

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

SOURCE

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

BUGS

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

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) 2020, 2017, 2016, 2015 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.