1MooseX::Role::Cmd(3) User Contributed Perl Documentation MooseX::Role::Cmd(3)
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6 MooseX::Role::Cmd - Wrap system command binaries the Moose way
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9 Create your command wrapper:
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11 package Cmd::Perl;
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13 use Moose;
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15 with 'MooseX::Role::Cmd';
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17 has 'e' => (isa => 'Str', is => 'rw');
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19 # other perl switches here...
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21 1;
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23 Use it somewhere else:
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25 use Cmd::Perl;
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27 my $perl = Cmd::Perl->new(e => q{'print join ", ", @ARGV'});
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29 print $perl->run(qw/foo bar baz/);
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31 # prints the STDOUT captured from running:
32 # perl -e 'print join ", ", @ARGV' foo bar baz
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35 MooseX::Role::Cmd is a Moose role intended to ease the task of building
36 command-line wrapper modules. It automatically maps Moose objects into
37 command strings which are passed to IPC::Cmd.
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40 $cmd->bin_name
41 Sets the binary executable name for the command you want to run.
42 Defaults the to last part of the class name.
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44 $cmd->stdout
45 Returns the STDOUT buffer captured after running the command.
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47 $cmd->stderr
48 Returns the STDERR buffer captured after running the command.
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51 $bin_name = $cmd->build_bin_name
52 Builds the default string for the command name based on the class name.
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54 @stdout = $cmd->run(@args);
55 Builds the command string and runs it based on the objects current
56 attribute settings. This will treat all the attributes defined in your
57 class as flags to be passed to the command.
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59 NOTE: All quoting issues are left to be solved by the user.
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61 cmd_args
62 Returns a list of the computed arguments that will be added to the
63 command
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66 Setting the Executable
67 By default the name of the binary executable is taken from the last
68 part of the class name (in lower case). The path is set during the run
69 method by scanning through your current PATH for the given executable
70 (see also the 'can_run' function from IPC::Cmd)
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72 package MyApp::Commands::Scanner;
73 use Moose;
74 with 'MooseX::Role::Cmd';
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76 $cmd = MyApp::Commands::Scanner->new();
77 $cmd->bin_name
78 # /path/to/scanner
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80 If this default behaviour doesn't suit your application then you can
81 override the build_bin_name subroutine to explicitly set the executable
82 name
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84 sub build_bin_name { 'scanner.exe' }
85 # /path/to/scanner.exe
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87 Or you could explicitly set the path with
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89 sub build_bin_name { '/only/use/this/path/scanner.exe' }
90 # /only/use/this/path/scanner.exe
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92 How attributes are mapped to parameters
93 The attributes of the consuming package map directly to the parameters
94 passed to the executable. There are a few things to note about the
95 default behaviour governing the way these attributes are mapped.
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97 Attribute Default Behaviour (@ARGV)
98 --------- -------------------------
99 single char prefix attr name with '-'
100 multiple char prefix attr name with '--'
101 boolean treat attr as flag (no value)
102 non-boolean treat attr as parameter (with value)
103 value=undef ignore attr
104 name=_name ignore attr
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106 These points are illustrated in the following example:
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108 package MyApp::Commands::Scanner;
109 use Moose;
110 with 'MooseX::Role::Cmd';
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112 has 'i' => ( is => 'rw', isa => 'Str', default => 'input.txt' );
113 has 'out' => ( is => 'rw', isa => 'Str' );
114 has 'verbose' => ( is => 'rw', isa => 'Bool', default => 1 );
115 has 'level' => ( is => 'rw', isa => 'Int' );
116 has 'option' => ( is => 'rw', isa => 'Str' );
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118 has '_internal' => ( is => 'ro', isa => Str, reader => internal, default => 'foo' );
119 # attribute names starting with '_' are not included
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121 $scanner = MyApp::Commands::Scanner->new( output => '/tmp/scanner.log', level => 5 );
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123 $scanner->run;
124 # /path/to/scanner -i input.txt --out /tmp/scanner.log --verbose --level 5
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126 Changing names of parameters
127 It's possible that the parameters your system command expects do not
128 adhere to this naming scheme. In this case you can use the 'CmdOpt'
129 trait which allows you to specify exactly how you want the parameter to
130 appear on the command line.
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132 has 'option' => ( isa => 'Bool' );
133 # --option
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135 cmdopt_prefix
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137 This lets you override the prefix used for the option (for example to
138 use the short form of multi-character options).
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140 has 'option' => ( traits => [ 'CmdOpt' ],
141 isa => 'Bool',
142 cmdopt_prefix => '-'
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144 # -option
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146 cmdopt_name
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148 This lets you completely override the option name with whatever string
149 you want
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151 has 'option' => ( traits => [ 'CmdOpt' ],
152 isa => 'Bool',
153 cmdopt_name => '+foo'
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155 # +foo
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157 cmdopt_env
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159 This will set an environment variable with the attribute name/value
160 rather than pass it along as a command line param
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162 has 'home_dir' => ( traits => [ 'CmdOpt' ],
163 isa => 'Str',
164 cmdopt_env => 'APP_HOME'
165 default => '/my/app/home'
166 );
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168 # ENV{APP_HOME} = /my/app/home
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170 See MooseX::Role::Cmd::Meta::Attribute::Trait
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173 _attr_to_cmd_options
174 Returns an array (or array reference) of command options that
175 correspond to the given attribute name.
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178 Eden Cardim <edencardim@gmail.com>
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181 This library is free software, you can redistribute it and/or modify it
182 under the same terms as Perl itself.
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186perl v5.34.0 2021-07-22 MooseX::Role::Cmd(3)