Provided by: libperinci-cmdline-perl_2.000.0-2_all 
NAME
Perinci::CmdLine::Manual - Perinci::CmdLine manual
VERSION
This document describes version 2.000.0 of Perinci::CmdLine::Manual (from Perl
distribution Perinci-CmdLine), released on 2021-12-19.
DESCRIPTION
Perinci::CmdLine is a command-line application framework. It parses command-line options
and dispatches to one of your specified Perl functions, passing the command-line options
and arguments to the function. It accesses functions via Riap protocol (using the
Perinci::Access Riap client library) so you can use remote functions transparently.
Features:
• Command-line options parsing
Non-scalar arguments (array, hash, other nested) can also be passed as JSON or YAML.
For example, if the "tags" argument is defined as 'array', then all of below are
equivalent:
% mycmd --tags-yaml '[foo, bar, baz]'
% mycmd --tags-json '["foo","bar","baz"]'
% mycmd --tags foo --tags bar --tags baz
• Help message (utilizing information from metadata, supports translation)
% mycmd --help
% mycmd -h
% mycmd -?
• Tab completion for various shells (including completion from remote code)
Example for bash:
% complete -C mycmd mycmd
% mycmd --he<tab> ; # --help
% mycmd s<tab> ; # sub1, sub2, sub3 (if those are the specified subcommands)
% mycmd sub1 -<tab> ; # list the options available for sub1 subcommand
• Undo/redo/history
If the function supports transaction (see Rinci::Transaction, Riap::Transaction) the
framework will setup transaction and provide command to do undo (--undo) and redo
(--redo) as well as seeing the undo/transaction list (--history) and clearing the list
(--clear-history).
• Version (--version, -v)
• List available subcommands (--subcommands)
• Configurable output format (--format, --format-options)
By default "yaml", "json", "text", "text-simple", "text-pretty" are recognized.
CONCEPTS
Perinci::CmdLine is very function-oriented (and not object-oriented, on purpose). You
write your "business logic" in a function (of course, you are free to subdivide or
delegate to other functions, but there must be one main function for a single-subcommand
CLI application, or one function for each subcommand in a multiple-subcommand CLI
application.
sub cliapp {
...
}
You annotate the function with Rinci metadata, where you describe what arguments (and
command-line aliases, if any) the function (program) accepts, the summary and description
of those arguments, and several other aspects as necessary.
$SPEC{cliapp} = {
v => 1.1,
summary => 'A program to do blah blah',
args => {
foo => {
summary => 'foo argument',
req => 1,
pos => 0,
cmdline_aliases => {f=>{}},
},
bar => { ... },
},
};
sub cliapp {
...
}
Finally, you "run" your function:
use Perinci::CmdLine::Any;
Perinci::CmdLine::Any->new(url => '/main/cliapp')->run;
For a multi-subcommand application:
Perinci::CmdLine::Any->new(
url => '/main/cliapp',
subcommands => {
sc1 => { url => '/main/do_sc1' },
sc2 => { url => '/main/do_sc2' },
...
},
)->run;
That's it. Command-line option parsing, help message, as well as tab completion will work
without extra effort.
To run a remote function, you can simply specify a remote URL, e.g.
"http://example.com/api/somefunc". All the features like options parsing, help/usage, as
well as tab completion will work with remote functions as well.
LOGGING
Logging is done with Log::ger (for producing). For displaying logs, Log::ger::App is used.
Initializing logging adds a bit to startup overhead time, so the framework defaults to no
logging. To turn on logging from the code, set the "log" attribute to true when
constructing Perinci::CmdLine object. Or, use something like:
% PERL5OPT=-MLog::ger::App TRACE=1 yourcli.pl
COMMAND-LINE OPTION/ARGUMENT PARSING
This section describes how Perinci::CmdLine parses command-line options/arguments into
function arguments. Command-line option parsing is implemented by
Perinci::Sub::GetArgs::Argv.
For boolean function arguments, use "--arg" to set "arg" to true (1), and "--noarg" to set
"arg" to false (0). A flag argument ("[bool => {is=>1}]") only recognizes "--arg" and not
"--noarg". For single letter arguments, only "-X" is recognized, not "--X" nor "--noX".
For string and number function arguments, use "--arg VALUE" or "--arg=VALUE" (or "-X
VALUE" for single letter arguments) to set argument value. Other scalar arguments use the
same way, except that some parsing will be done (e.g. for date type, --arg 1343920342 or
--arg '2012-07-31' can be used to set a date value, which will be a DateTime object.)
(Note that date parsing will be done by Data::Sah and currently not implemented yet.)
For arguments with type array of scalar, a series of "--arg VALUE" is accepted, a la
Getopt::Long:
--tags tag1 --tags tag2 ; # will result in tags => ['tag1', 'tag2']
For other non-scalar arguments, also use "--arg VALUE" or "--arg=VALUE", but VALUE will be
attempted to be parsed using JSON, and then YAML. This is convenient for common cases:
--aoa '[[1],[2],[3]]' # parsed as JSON
--hash '{a: 1, b: 2}' # parsed as YAML
For explicit JSON parsing, all arguments can also be set via --ARG-json. This can be used
to input undefined value in scalars, or setting array value without using repetitive
"--arg VALUE":
--str-json 'null' # set undef value
--ary-json '[1,2,3]' # set array value without doing --ary 1 --ary 2 --ary 3
--ary-json '[]' # set empty array value
Likewise for explicit YAML parsing:
--str-yaml '~' # set undef value
--ary-yaml '[a, b]' # set array value without doing --ary a --ary b
--ary-yaml '[]' # set empty array value
Submetadata. Arguments from submetadata will also be given respective command-line options
(and aliases) with prefixed names. For example this function metadata:
{
v => 1.1,
args => {
foo => {schema=>'str*'},
bar => {
schema => 'hash*',
meta => {
v => 1.1,
args => {
baz => {schema=>'str*'},
qux => {
schema=>'str*,
},
},
},
},
quux => {
schema => 'array*',
element_meta => {
v => 1.1,
args => {
corge => {schema=>'str*', cmdline_aliases=>{C=>{}},
grault => {schema=>'str*'},
},
},
},
},
}
You can specify on the command-line:
% prog --foo val \
--bar-baz val --bar-qux val \
--quux-corge 11 \
--quux-corge 21 --quux-grault 22 \
--quux-C 31
The resulting argument will be:
{
foo => 'val',
bar => {
baz => 'val',
qux => 'val',
},
quux => [
{corge=>11},
{corge=>21, grault=>22},
{corge=>31},
],
}
For more examples on argument submetadata, see Perinci::Examples::SubMeta.
SHELL COMPLETION
The framework can detect when "COMP_LINE" and "COMP_POINT" environment variables (set by
bash when completing using external command) are set and then answer the completion. In
bash, activating tab completion for your script is as easy as (assuming your script is
already in PATH):
% complete -C yourscript yourscript
That is, your script can complete itself (but scripts generated with
Perinci::CmdLine::Inline are equipped with companion scripts for completion). The above
command can be put in ~/.bashrc. But it is recommended that you use shcompgen instead (see
below).
Tcsh uses "COMMAND_LINE" instead. The framework can also detect that.
For other shells: some shells can emulate bash (like zsh) and for some other (like fish)
you need to generate a set of "complete" commands for each command-line option.
"shcompgen" is a CLI tool that can detect all scripts in PATH if they are using
Perinci::CmdLine (as well as a few other frameworks) and generate shell completion scripts
for them. It supports several shells. Combined with cpanm-shcompgen, you can install
modules and have the shell completion of scripts activated immediately.
PROGRESS INDICATOR
For functions that express that they do progress updating (by setting their "progress"
feature to true), Perinci::CmdLine will setup an output, currently either
Progress::Any::Output::TermProgressBar if program runs interactively.
CONFIGURATION FILE
Configuration files are read to preset the value of arguments, before potentially
overridden/merged with command-line options. Configuration files are in IOD format, which
is basically "INI" with some extra features.
By default, configuration files are searched in home directory then "/etc", with the name
of program_name + ".conf". If multiple files are found, the contents are merged together.
If user wants to use a custom configuration file, she can issue "--config-path" command-
line option.
If user does not want to read configuration file, she can issue "--no-config" command-line
option.
INI files have the concept of "sections". In Perinci::CmdLine, you can use sections to put
settings that will only be applied to a certain subcommand, or a certain "profile", or
other conditions. "Config profiles" is a way to specify multiple sets/cases/scenarios in a
single configuration file.
Example 1 (without any profile or subcommand):
; prog.conf
foo=1
bar=2
When executing program (the comments will show what arguments are set):
% prog; # {foo=>1, bar=>2}
% prog --foo 10; # {foo=>10, bar=>2}
Example 2 (with profiles):
; prog.conf
[profile=profile1]
foo=1
bar=2
[profile=profile2]
foo=10
bar=20
When executing program:
% prog; # {}
% prog --config-profile profile1; # {foo=>1, bar=>2}
% prog --config-profile profile2; # {foo=>10, bar=>20}
Example 3 (with subcommands):
; prog.conf
[subcommand=sc1]
foo=1
bar=2
[subcommand=sc2]
baz=3
qux=4
When executing program:
% prog sc1; # {foo=>1, bar=>2}
% prog sc2; # {baz=>3, qux=>4}
Example 4 (with subcommands and profiles):
; prog.conf
[subcommand=sc1 profile=profile1]
foo=1
bar=2
[profile=profile2 subcommand=sc1]
foo=10
bar=20
When executing program:
% prog sc1 --config-profile profile1; # {foo=>1, bar=>2}
% prog sc1 --config-profile profile2; # {foo=>10, bar=>20}
HOMEPAGE
Please visit the project's homepage at <https://metacpan.org/release/Perinci-CmdLine>.
SOURCE
Source repository is at <https://github.com/perlancar/perl-Perinci-CmdLine>.
SEE ALSO
Perinci::CmdLine::Manual::Examples
Perinci::CmdLine::Manual::FAQ
A list of tutorial posts on my blog, will eventually be moved to POD:
<https://perlancar.wordpress.com/category/pericmd-tut/>
AUTHOR
perlancar <perlancar@cpan.org>
CONTRIBUTING
To contribute, you can send patches by email/via RT, or send pull requests on GitHub.
Most of the time, you don't need to build the distribution yourself. You can simply modify
the code, then test via:
% prove -l
If you want to build the distribution (e.g. to try to install it locally on your system),
you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, and sometimes
one or two other Dist::Zilla plugin and/or Pod::Weaver::Plugin. Any additional steps
required beyond that are considered a bug and can be reported to me.
COPYRIGHT AND LICENSE
This software is copyright (c) 2021, 2018, 2017, 2016, 2015 by perlancar
<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.
BUGS
Please report any bugs or feature requests on the bugtracker website
<https://rt.cpan.org/Public/Dist/Display.html?Name=Perinci-CmdLine>
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.