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NAME

Applify - Write object oriented scripts with ease

VERSION

0.22

DESCRIPTION

This module should keep all the noise away and let you write scripts very easily. These scripts can even be unit tested even though they are defined directly in the script file and not in a module.

SYNOPSIS

  #!/usr/bin/perl
  use Applify;

  option file => input_file => 'File to read from';
  option dir => output_dir => 'Directory to write files to';
  option flag => dry_run => 'Use --no-dry-run to actually do something', 1;

  documentation __FILE__;
  version 1.23;

  sub generate_exit_value {
    return int rand 100;
  }

  # app {...}; must be the last statement in the script
  app {
    my ($app, @extra) = @_;
    my $exit_value = 0;

    print "Extra arguments: @extra\n" if(@extra);
    print "Will read from: ", $app->input_file, "\n";
    print "Will write files to: ", $app->output_dir, "\n";

    if($app->dry_run) {
      die 'Will not run script';
    }

    return $app->generate_exit_value;
  };

APPLICATION CLASS

This module will generate an application class, which $app inside the "app" block is an instance of. The class will have these methods:

  • new()

    An object constructor. This method will not be auto generated if any of the classes given to "extends" has the method new().

  • run()

    This method is basically the code block given to "app".

  • Other methods

    Other methods defined in the script file will be accesible from $app inside app{}.

  • _script()

    This is an accessor which return the Applify object which is refered to as $script in this documentation.

    NOTE: This accessor starts with an underscore to prevent conflicts with "options".

  • Other accessors

    Any "option" (application option) will be available as an accessor on the application object.

EXPORTED FUNCTIONS

option

  option $type => $name => $documentation;
  option $type => $name => $documentation, $default;
  option $type => $name => $documentation, $default, @args;
  option $type => $name => $documentation, @args;

This function is used to define options which can be given to this application. See "SYNOPSIS" for example code. This function can also be called as a method on $script. Additionally, similar to Moose attributes, a has_$name method will be generated, which can be called on $app to determine if the "option" has been set, either by a user or from the $default.

  • $type

    Used to define value types for this input. Can be:

      | $type | Example             | Attribute value |
      |-------|---------------------|-----------------|
      | bool  | --foo, --no-foo     | foo=1, foo=0    |
      | flag  | --foo, --no-foo     | foo=1, foo=0    |
      | inc   | --verbose --verbose | verbose=2       |
      | str   | --name batwoman     | name=batwoman   |
      | int   | --answer 42         | answer=42       |
      | num   | --pie 3.14          | pie=3.14        |
  • $name

    The name of an application option. This name will also be used as accessor name inside the application. Example:

      # define an application option: 
      option file => some_file => '...';
    
      # call the application from command line:
      > myapp.pl --some-file /foo/bar
    
      # run the application code:
      app {
        my $app = shift;
        print $app->some_file # prints "/foo/bar"
        return 0;
      };
  • $documentation

    Used as description text when printing the usage text.

  • $default

    Either a plain value or a code ref that can be used to generate a value.

      option str => passwd => "Password file", "/etc/passwd";
      option str => passwd => "Password file", sub { "/etc/passwd" };
  • @args

    • alias

      Used to define an alias for the option. Example:

        option inc => verbose => "Output debug information", alias => "v";
    • required

      The script will not start if a required field is omitted.

    • n_of

      Allow the option to hold a list of values. Examples: "@", "4", "1,3". See "Options-with-multiple-values" in Getopt::Long for details.

    • isa

      Can be used to either specify a class that the value should be instantiated as, or a Type::Tiny object that will be used for coercion and/or type validation.

      Example using a class:

        option file => output => "output file", isa => "Mojo::File";

      The output() attribute will then later return an object of Mojo::File, instead of just a plain string.

      Example using Type::Tiny:

        use Types::Standard "Int";
        option num => age => "Your age", isa => Int;
    • Other

      Any other Moose attribute argument may/will be supported in future release.

documentation

  documentation __FILE__; # current file
  documentation '/path/to/file';
  documentation 'Some::Module';

Specifies where to retrieve documentaion from when giving the --man option to your script.

version

  version 'Some::Module';
  version $num;

Specifies where to retrieve the version number from when giving the --version option to your script.

extends

  extends @classes;

Specify which classes this application should inherit from. These classes can be Moose based.

hook

  hook before_exit            => sub { my ($script, $exit_value) = @_ };
  hook before_options_parsing => sub { my ($script, $argv) = @_ };

Defines a hook to run.

  • before_exit

    Called right before exit($exit_value) is called by Applify. Note that this hook will not be called if an exception is thrown.

  • before_options_parsing

    Called right before $argv is parsed by "option_parser". $argv is an array-ref of the raw options given to your application. This hook allows you to modify "option_parser". Example:

      hook before_options_parsing => sub {
        shift->option_parser->configure(bundling no_pass_through);
      };

subcommand

  subcommand list => 'provide a listing objects' => sub {
    option flag => long => 'long listing';
    option flag => recursive => 'recursively list objects';
  };

  subcommand create => 'create a new object' => sub {
    option str => name => 'name of new object', required => 1;
    option str => description => 'description for the object', required => 1;
  };

  sub command_create {
    my ($app, @extra) = @_;
    ## do creating
    return 0;
  }

  sub command_list {
    my ($app, @extra) = @_;
    ## do listing
    return 0;
  }

  app {
    my ($app, @extra) = @_;
    ## fallback when no command given.
    $app->_script->print_help;
    return 0;
  };

This function allows for creating multiple related sub commands within the same script in a similar fashion to git. The "option", "extends" and "documentation" exported functions may sensibly be called within the subroutine. Calling the function with no arguments will return the running subcommand, i.e. a valid $ARGV[0]. Non valid values for the subcommand given on the command line will result in the help being displayed.

app

  app CODE;

This function will define the code block which is called when the application is started. See "SYNOPSIS" for example code. This function can also be called as a method on $script.

IMPORTANT: This function must be the last function called in the script file for unit tests to work. Reason for this is that this function runs the application in void context (started from command line), but returns the application object in list/scalar context (from "do" in perlfunc).

ATTRIBUTES

option_parser

  $script = $script->option_parser(Getopt::Long::Parser->new);
  $parser = $script->option_parser;

You can specify your own option parser if you have special needs. The default is:

  Getopt::Long::Parser->new(config => [qw(no_auto_help no_auto_version pass_through)]);

options

  $array_ref = $script->options;

Holds the application options given to "option".

METHODS

new

  $script = Applify->new({options => $array_ref, ...});

Object constructor. Creates a new object representing the script meta information.

Will print "options" to selected filehandle (STDOUT by default) in a normalized matter. Example:

  Usage:
     --foo      Foo does this and that
   * --bar      Bar does something else

     --help     Print this help text
     --man      Display manual for this application
     --version  Print application name and version

Will print "version" to selected filehandle (STDOUT by default) in a normalized matter. Example:

  some-script.pl version 1.23

import

Will export the functions listed under "EXPORTED FUNCTIONS". The functions will act on a Applify object created by this method.

COPYRIGHT & LICENSE

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

AUTHORS

Jan Henning Thorsen - jhthorsen@cpan.org

Roy Storey - kiwiroy@cpan.org