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NAME

Perinci::Sub::GetArgs::Argv - Get subroutine arguments from command line arguments (@ARGV)

VERSION

This document describes version 0.850 of Perinci::Sub::GetArgs::Argv (from Perl distribution Perinci-Sub-GetArgs-Argv), released on 2023-02-24.

SYNOPSIS

use Perinci::Sub::GetArgs::Argv;

my $res = get_args_from_argv(argv=>\@ARGV, meta=>$meta, ...);

DESCRIPTION

This module provides get_args_from_argv(), which parses command line arguments (@ARGV) into subroutine arguments (%args). This module is used by Perinci::CmdLine. For explanation on how command-line options are processed, see Perinci::CmdLine's documentation.

FUNCTIONS

gen_getopt_long_spec_from_meta

Usage:

gen_getopt_long_spec_from_meta(%args) -> [$status_code, $reason, $payload, \%result_meta]

Generate Getopt::Long spec from Rinci function metadata.

This routine will produce a Getopt::Long specification from Rinci function metadata, as well as some more data structure in the result metadata to help producing a command-line help/usage message.

Function arguments will be mapped to command-line options with the same name, with non-alphanumeric characters changed to - (- is preferred over _ because it lets user avoid pressing Shift on popular keyboards). For example: file_size becomes file-size, file_size.max becomes file-size-max. If function argument option name clashes with command-line option or another existing option, it will be renamed to NAME-arg (or NAME-arg2 and so on). For example: help will become help-arg (if common_opts contains help, that is).

Each command-line alias (cmdline_aliases property) in the argument specification will also be added as command-line option, except if it clashes with an existing option, in which case this function will warn and skip adding the alias. For more information about cmdline_aliases, see Rinci::function.

For arguments with type of bool, Getopt::Long will by default also automatically recognize --noNAME or --no-NAME in addition to --name. So this function will also check those names for clashes.

For arguments with type array of simple scalar, --NAME can be specified more than once to append to the array.

If per_arg_json setting is active, and argument's schema is not a "required simple scalar" (e.g. an array, or a nullable string), then --NAME-json will also be added to let users input undef (through --NAME-json null) or a non-scalar value (e.g. --NAME-json '[1,2,3]'). If this name conflicts with another existing option, a warning will be displayed and the option will not be added.

If per_arg_yaml setting is active, and argument's schema is not a "required simple scalar" (e.g. an array, or a nullable string), then --NAME-yaml will also be added to let users input undef (through --NAME-yaml '~') or a non-scalar value (e.g. --NAME-yaml '[foo, bar]'). If this name conflicts with another existing option, a warning will be displayed and the option will not be added. YAML can express a larger set of values, e.g. binary data, circular references, etc.

Will produce a hash (Getopt::Long spec), with func.specmeta, func.opts, func.common_opts, func.func_opts that contain extra information (func.specmeta is a hash of getopt spec name and a hash of extra information while func.*opts lists all used option names).

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

  • args => hash

    Reference to hash which will store the result.

  • common_opts => hash

    Common options.

    A hash where the values are hashes containing these keys: getopt (Getopt::Long option specification), handler (Getopt::Long handler). Will be passed to get_args_from_argv(). Example:

    {
        help => {
            getopt  => 'help|h|?',
            handler => sub { ... },
            summary => 'Display help and exit',
        },
        version => {
            getopt  => 'version|v',
            handler => sub { ... },
            summary => 'Display version and exit',
        },
    }
  • ignore_converted_code => bool (default: 0)

    Whether to ignore coderefs converted to string.

    Across network through JSON encoding, coderef in metadata (e.g. in cmdline_aliases property) usually gets converted to string CODE. In some cases, like for tab completion, this is pretty harmless so you can turn this option on. For example, in the case of cmdline_aliases, the effect is just that command-line aliases code are not getting executed, but this is usually okay.

  • meta* => hash

    Rinci function metadata.

  • meta_is_normalized => bool

    (No description)

  • per_arg_json => bool (default: 0)

    Whether to add --NAME-json for non-simple arguments.

    Will also interpret command-line arguments as JSON if assigned to function arguments, if arguments' schema is not simple scalar.

  • per_arg_yaml => bool (default: 0)

    Whether to add --NAME-yaml for non-simple arguments.

    Will also interpret command-line arguments as YAML if assigned to function arguments, if arguments' schema is not simple scalar.

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)

get_args_from_argv

Usage:

get_args_from_argv(%args) -> [$status_code, $reason, $payload, \%result_meta]

Get subroutine arguments (%args) from command-line arguments (@ARGV).

Using information in Rinci function metadata's args property, parse command line arguments @argv into hash %args, suitable for passing into subroutines.

Currently uses Getopt::Long's GetOptions to do the parsing.

As with GetOptions, this function modifies its argv argument, so you might want to copy the original argv first (or pass a copy instead) if you want to preserve the original.

See also: gen_getopt_long_spec_from_meta() which is the routine that generates the specification.

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

  • allow_extra_elems => bool (default: 0)

    Allow extra/unassigned elements in argv.

    If set to 1, then if there are array elements unassigned to one of the arguments, instead of generating an error, this function will just ignore them.

    This option will be passed to Perinci::Sub::GetArgs::Array's allow_extra_elems.

  • args => hash

    Specify input args, with some arguments preset.

  • argv => array[str]

    If not specified, defaults to @ARGV

  • common_opts => hash

    Common options.

    A hash where the values are hashes containing these keys: getopt (Getopt::Long option specification), handler (Getopt::Long handler). Will be passed to get_args_from_argv(). Example:

    {
        help => {
            getopt  => 'help|h|?',
            handler => sub { ... },
            summary => 'Display help and exit',
        },
        version => {
            getopt  => 'version|v',
            handler => sub { ... },
            summary => 'Display version and exit',
        },
    }
  • ggls_res => array

    Full result from gen_getopt_long_spec_from_meta().

    If you already call gen_getopt_long_spec_from_meta(), you can pass the full enveloped result here, to avoid calculating twice.

  • ignore_converted_code => bool (default: 0)

    Whether to ignore coderefs converted to string.

    Across network through JSON encoding, coderef in metadata (e.g. in cmdline_aliases property) usually gets converted to string CODE. In some cases, like for tab completion, this is harmless so you can turn this option on.

  • meta* => hash

    (No description)

  • meta_is_normalized => bool (default: 0)

    Can be set to 1 if your metadata is normalized, to avoid duplicate effort.

  • on_missing_required_args => code

    Execute code when there is missing required args.

    This can be used to give a chance to supply argument value from other sources if not specified by command-line options. Perinci::CmdLine, for example, uses this hook to supply value from STDIN or file contents (if argument has cmdline_src specification key set).

    This hook will be called for each missing argument. It will be supplied hash arguments: (arg => $the_missing_argument_name, args => $the_resulting_args_so_far, spec => $the_arg_spec).

    The hook can return true if it succeeds in making the missing situation resolved. In this case, this function will not report the argument as missing.

  • per_arg_json => bool (default: 0)

    Whether to recognize --ARGNAME-json.

    This is useful for example if you want to specify a value which is not expressible from the command-line, like 'undef'.

    % script.pl --name-json 'null'

    But every other string will need to be quoted:

    % script.pl --name-json '"foo"'

    See also: per_arg_yaml. You should enable just one instead of turning on both.

  • per_arg_yaml => bool (default: 0)

    Whether to recognize --ARGNAME-yaml.

    This is useful for example if you want to specify a value which is not expressible from the command-line, like 'undef'.

    % script.pl --name-yaml '~'

    See also: per_arg_json. You should enable just one instead of turning on both.

  • strict => bool (default: 1)

    Strict mode.

    If set to 0, will still return parsed argv even if there are parsing errors (reported by Getopt::Long). If set to 1 (the default), will die upon error.

    Normally you would want to use strict mode, for more error checking. Setting off strict is used by, for example, Perinci::Sub::Complete during completion where the command-line might still be incomplete.

    Should probably be named ignore_errors or allow_unknown_options. :-)

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)

Error codes:

  • 400 - Error in Getopt::Long option specification, e.g. in common_opts.

  • 500 - failure in GetOptions, meaning argv is not valid according to metadata specification (only if 'strict' mode is enabled).

  • 501 - coderef in cmdline_aliases got converted into a string, probably because the metadata was transported (e.g. through Riap::HTTP/Riap::Simple).

FAQ

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Perinci-Sub-GetArgs-Argv.

SOURCE

Source repository is at https://github.com/perlancar/perl-Perinci-Sub-GetArgs-Argv.

SEE ALSO

Perinci

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTORS

  • Olivier Mengué <dolmen@cpan.org>

  • Steven Haryanto <stevenharyanto@gmail.com>

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, Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2023, 2022, 2021, 2020, 2019, 2017, 2016, 2015, 2014, 2013, 2012, 2011 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-Sub-GetArgs-Argv

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.