File: Getopt.pm

package info (click to toggle)
libmoosex-getopt-perl 0.15-1
  • links: PTS, VCS
  • area: main
  • in suites: lenny
  • size: 256 kB
  • ctags: 151
  • sloc: perl: 2,731; makefile: 15
file content (467 lines) | stat: -rw-r--r-- 13,588 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467

package MooseX::Getopt;
use Moose::Role;

use MooseX::Getopt::OptionTypeMap;
use MooseX::Getopt::Meta::Attribute;
use MooseX::Getopt::Meta::Attribute::NoGetopt;

use Carp ();

use Getopt::Long (); # GLD uses it anyway, doesn't hurt
use constant HAVE_GLD => not not eval { require Getopt::Long::Descriptive };

our $VERSION   = '0.15';
our $AUTHORITY = 'cpan:STEVAN';

has ARGV       => (is => 'rw', isa => 'ArrayRef', metaclass => "NoGetopt");
has extra_argv => (is => 'rw', isa => 'ArrayRef', metaclass => "NoGetopt");

sub new_with_options {
    my ($class, @params) = @_;

    my $config_from_file;
    if($class->meta->does_role('MooseX::ConfigFromFile')) {
        local @ARGV = @ARGV;

        my $configfile;
        my $opt_parser = Getopt::Long::Parser->new( config => [ qw( pass_through ) ] );
        $opt_parser->getoptions( "configfile=s" => \$configfile );

        if(!defined $configfile) {
            my $cfmeta = $class->meta->find_attribute_by_name('configfile');
            $configfile = $cfmeta->default if $cfmeta->has_default;
        }

        if(defined $configfile) {
            $config_from_file = $class->get_config_from_file($configfile);
        }
    }

    my $constructor_params = ( @params == 1 ? $params[0] : {@params} );
    
    Carp::croak("Single parameters to new_with_options() must be a HASH ref")
        unless ref($constructor_params) eq 'HASH';

    my %processed = $class->_parse_argv(
        options => [
            $class->_attrs_to_options( $config_from_file )
        ],
        params => $constructor_params,
    );

    my $params = $config_from_file ? { %$config_from_file, %{$processed{params}} } : $processed{params};

    $class->new(
        ARGV       => $processed{argv_copy},
        extra_argv => $processed{argv},
        @params, # explicit params to ->new
        %$params, # params from CLI
    );
}

sub _parse_argv {
    my ( $class, %params ) = @_;

    local @ARGV = @{ $params{argv} || \@ARGV };

    my ( $opt_spec, $name_to_init_arg ) = ( HAVE_GLD ? $class->_gld_spec(%params) : $class->_traditional_spec(%params) );

    # Get a clean copy of the original @ARGV
    my $argv_copy = [ @ARGV ];

    my @err;

    my ( $parsed_options, $usage ) = eval {
        local $SIG{__WARN__} = sub { push @err, @_ };

        if ( HAVE_GLD ) {
            return Getopt::Long::Descriptive::describe_options($class->_usage_format(%params), @$opt_spec);
        } else {
            my %options;
            Getopt::Long::GetOptions(\%options, @$opt_spec);
            return ( \%options, undef );
        }
    };

    die join "", grep { defined } @err, $@ if @err or $@;

    # Get a copy of the Getopt::Long-mangled @ARGV
    my $argv_mangled = [ @ARGV ];

    my %constructor_args = (
        map {
            $name_to_init_arg->{$_} => $parsed_options->{$_}
        } keys %$parsed_options,
    );

    return (
        params    => \%constructor_args,
        argv_copy => $argv_copy,
        argv      => $argv_mangled,
        ( defined($usage) ? ( usage => $usage ) : () ),
    );
}

sub _usage_format {
    return "usage: %c %o";
}

sub _traditional_spec {
    my ( $class, %params ) = @_;

    my ( @options, %name_to_init_arg, %options );

    foreach my $opt ( @{ $params{options} } ) {
        push @options, $opt->{opt_string};

        my $identifier = $opt->{name};
        $identifier =~ s/\W/_/g; # Getopt::Long does this to all option names

        $name_to_init_arg{$identifier} = $opt->{init_arg};
    }

    return ( \@options, \%name_to_init_arg );
}

sub _gld_spec {
    my ( $class, %params ) = @_;

    my ( @options, %name_to_init_arg );

    my $constructor_params = $params{params};

    foreach my $opt ( @{ $params{options} } ) {
        push @options, [
            $opt->{opt_string},
            $opt->{doc} || ' ', # FIXME new GLD shouldn't need this hack
            {
                ( ( $opt->{required} && !exists($constructor_params->{$opt->{init_arg}}) ) ? (required => $opt->{required}) : () ),
                # NOTE:
                # remove this 'feature' because it didn't work 
                # all the time, and so is better to not bother
                # since Moose will handle the defaults just 
                # fine anyway.
                # - SL
                #( exists $opt->{default}  ? (default  => $opt->{default})  : () ),
            },
        ];

        my $identifier = $opt->{name};
        $identifier =~ s/\W/_/g; # Getopt::Long does this to all option names

        $name_to_init_arg{$identifier} = $opt->{init_arg};
    }

    return ( \@options, \%name_to_init_arg );
}

sub _compute_getopt_attrs {
    my $class = shift;
    grep {
        $_->does("MooseX::Getopt::Meta::Attribute::Trait")
            or
        $_->name !~ /^_/
    } grep {
        !$_->does('MooseX::Getopt::Meta::Attribute::Trait::NoGetopt')
    } $class->meta->compute_all_applicable_attributes
}

sub _get_cmd_flags_for_attr {
    my ( $class, $attr ) = @_;

    my $flag = $attr->name;

    my @aliases;

    if ($attr->does('MooseX::Getopt::Meta::Attribute::Trait')) {
        $flag = $attr->cmd_flag if $attr->has_cmd_flag;
        @aliases = @{ $attr->cmd_aliases } if $attr->has_cmd_aliases;
    }

    return ( $flag, @aliases );
}

sub _attrs_to_options {
    my $class = shift;
    my $config_from_file = shift || {};

    my @options;

    foreach my $attr ($class->_compute_getopt_attrs) {
        my ( $flag, @aliases ) = $class->_get_cmd_flags_for_attr($attr);

        my $opt_string = join(q{|}, $flag, @aliases);

        if ($attr->has_type_constraint) {
            my $type = $attr->type_constraint;
            if (MooseX::Getopt::OptionTypeMap->has_option_type($type)) {
                $opt_string .= MooseX::Getopt::OptionTypeMap->get_option_type($type)
            }
        }

        push @options, {
            name       => $flag,
            init_arg   => $attr->init_arg,
            opt_string => $opt_string,
            required   => $attr->is_required && !$attr->has_default && !$attr->has_builder && !exists $config_from_file->{$attr->name},
            # NOTE:
            # this "feature" was breaking because 
            # Getopt::Long::Descriptive would return 
            # the default value as if it was a command 
            # line flag, which would then override the
            # one passed into a constructor.
            # See 100_gld_default_bug.t for an example
            # - SL
            #( ( $attr->has_default && ( $attr->is_default_a_coderef xor $attr->is_lazy ) ) ? ( default => $attr->default({}) ) : () ),
            ( $attr->has_documentation ? ( doc => $attr->documentation ) : () ),
        }
    }

    return @options;
}

no Moose::Role; 1;

__END__

=pod

=head1 NAME

MooseX::Getopt - A Moose role for processing command line options

=head1 SYNOPSIS

  ## In your class
  package My::App;
  use Moose;

  with 'MooseX::Getopt';

  has 'out' => (is => 'rw', isa => 'Str', required => 1);
  has 'in'  => (is => 'rw', isa => 'Str', required => 1);

  # ... rest of the class here

  ## in your script
  #!/usr/bin/perl

  use My::App;

  my $app = My::App->new_with_options();
  # ... rest of the script here

  ## on the command line
  % perl my_app_script.pl -in file.input -out file.dump

=head1 DESCRIPTION

This is a role which provides an alternate constructor for creating
objects using parameters passed in from the command line.

This module attempts to DWIM as much as possible with the command line
params by introspecting your class's attributes. It will use the name
of your attribute as the command line option, and if there is a type
constraint defined, it will configure Getopt::Long to handle the option
accordingly.

You can use the trait L<MooseX::Getopt::Meta::Attribute::Trait> or the
attribute metaclass L<MooseX::Getopt::Meta::Attribute> to get non-default
commandline option names and aliases.

You can use the trait L<MooseX::Getopt::Meta::Attribute::Trait::NoGetopt>
or the attribute metaclass L<MooseX::Getopt::Meta::Attribute::NoGetopt>
to have C<MooseX::Getopt> ignore your attribute in the commandline options.

By default, attributes which start with an underscore are not given
commandline argument support, unless the attribute's metaclass is set
to L<MooseX::Getopt::Meta::Attribute>. If you don't want you accessors
to have the leading underscore in thier name, you can do this:

  # for read/write attributes
  has '_foo' => (accessor => 'foo', ...);

  # or for read-only attributes
  has '_bar' => (reader => 'bar', ...);

This will mean that Getopt will not handle a --foo param, but your
code can still call the C<foo> method.

If your class also uses a configfile-loading role based on
L<MooseX::ConfigFromFile>, such as L<MooseX::SimpleConfig>,
L<MooseX::Getopt>'s C<new_with_options> will load the configfile
specified by the C<--configfile> option (or the default you've
given for the configfile attribute) for you.

Options specified in multiple places follow the following
precendence order: commandline overrides configfile, which
overrides explicit new_with_options parameters.

=head2 Supported Type Constraints

=over 4

=item I<Bool>

A I<Bool> type constraint is set up as a boolean option with
Getopt::Long. So that this attribute description:

  has 'verbose' => (is => 'rw', isa => 'Bool');

would translate into C<verbose!> as a Getopt::Long option descriptor,
which would enable the following command line options:

  % my_script.pl --verbose
  % my_script.pl --noverbose

=item I<Int>, I<Float>, I<Str>

These type constraints are set up as properly typed options with
Getopt::Long, using the C<=i>, C<=f> and C<=s> modifiers as appropriate.

=item I<ArrayRef>

An I<ArrayRef> type constraint is set up as a multiple value option
in Getopt::Long. So that this attribute description:

  has 'include' => (
      is      => 'rw',
      isa     => 'ArrayRef',
      default => sub { [] }
  );

would translate into C<includes=s@> as a Getopt::Long option descriptor,
which would enable the following command line options:

  % my_script.pl --include /usr/lib --include /usr/local/lib

=item I<HashRef>

A I<HashRef> type constraint is set up as a hash value option
in Getopt::Long. So that this attribute description:

  has 'define' => (
      is      => 'rw',
      isa     => 'HashRef',
      default => sub { {} }
  );

would translate into C<define=s%> as a Getopt::Long option descriptor,
which would enable the following command line options:

  % my_script.pl --define os=linux --define vendor=debian

=back

=head2 Custom Type Constraints

It is possible to create custom type constraint to option spec
mappings if you need them. The process is fairly simple (but a
little verbose maybe). First you create a custom subtype, like
so:

  subtype 'ArrayOfInts'
      => as 'ArrayRef'
      => where { scalar (grep { looks_like_number($_) } @$_)  };

Then you register the mapping, like so:

  MooseX::Getopt::OptionTypeMap->add_option_type_to_map(
      'ArrayOfInts' => '=i@'
  );

Now any attribute declarations using this type constraint will
get the custom option spec. So that, this:

  has 'nums' => (
      is      => 'ro',
      isa     => 'ArrayOfInts',
      default => sub { [0] }
  );

Will translate to the following on the command line:

  % my_script.pl --nums 5 --nums 88 --nums 199

This example is fairly trivial, but more complex validations are
easily possible with a little creativity. The trick is balancing
the type constraint validations with the Getopt::Long validations.

Better examples are certainly welcome :)

=head2 Inferred Type Constraints

If you define a custom subtype which is a subtype of one of the
standard L</Supported Type Constraints> above, and do not explicitly
provide custom support as in L</Custom Type Constraints> above,
MooseX::Getopt will treat it like the parent type for Getopt
purposes.

For example, if you had the same custom C<ArrayOfInts> subtype
from the examples above, but did not add a new custom option
type for it to the C<OptionTypeMap>, it would be treated just
like a normal C<ArrayRef> type for Getopt purposes (that is,
C<=s@>).

=head1 METHODS

=over 4

=item B<new_with_options (%params)>

This method will take a set of default C<%params> and then collect
params from the command line (possibly overriding those in C<%params>)
and then return a newly constructed object.

If L<Getopt::Long/GetOptions> fails (due to invalid arguments),
C<new_with_options> will throw an exception.

If you have L<Getopt::Long::Descriptive> a the C<usage> param is also passed to
C<new>.

=item B<ARGV>

This accessor contains a reference to a copy of the C<@ARGV> array
as it originally existed at the time of C<new_with_options>.

=item B<extra_argv>

This accessor contains an arrayref of leftover C<@ARGV> elements that
L<Getopt::Long> did not parse.  Note that the real C<@ARGV> is left
un-mangled.

=item B<meta>

This returns the role meta object.

=back

=head1 BUGS

All complex software has bugs lurking in it, and this module is no
exception. If you find a bug please either email me, or add the bug
to cpan-RT.

=head1 AUTHOR

Stevan Little E<lt>stevan@iinteractive.comE<gt>

Brandon L. Black, E<lt>blblack@gmail.comE<gt>

Yuval Kogman, E<lt>nothingmuch@woobling.orgE<gt>

=head1 CONTRIBUTORS

Ryan D Johnson, E<lt>ryan@innerfence.comE<gt>

=head1 COPYRIGHT AND LICENSE

Copyright 2007-2008 by Infinity Interactive, Inc.

L<http://www.iinteractive.com>

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

=cut