Commit | Line | Data |
c35b639e |
1 | package MooseX::ConfigFromFile; |
2 | |
3 | use Moose::Role; |
4 | use MooseX::Types::Path::Class qw( File ); |
5 | |
6 | our $VERSION = '0.01'; |
7 | |
8 | requires 'get_config_from_file'; |
9 | |
10 | has configfile => ( |
11 | is => 'ro', |
12 | isa => File, |
13 | coerce => 1, |
14 | predicate => 'has_configfile', |
15 | ); |
16 | |
17 | sub new_with_config { |
18 | my ($class, %opts) = @_; |
19 | |
20 | if($opts{configfile}) { |
21 | %opts = (%{$class->get_config_from_file($opts{configfile})}, %opts); |
22 | } |
23 | $class->new(%opts); |
24 | } |
25 | |
26 | no Moose::Role; 1; |
27 | |
28 | __END__ |
29 | |
30 | =pod |
31 | |
32 | =head1 NAME |
33 | |
34 | MooseX::ConfigFromFile - An abstract Moose role for setting attributes from a configfile |
35 | |
36 | =head1 SYNOPSIS |
37 | |
38 | ######## |
39 | ## A real role based on this abstract role: |
40 | ######## |
41 | |
42 | package MooseX::SomeSpecificConfigRole; |
43 | use Moose::Role; |
44 | |
45 | with 'MooseX::ConfigFromFile'; |
46 | |
47 | use Some::ConfigFile::Loader (); |
48 | |
49 | sub get_config_from_file { |
50 | my ($class, $file) = @_; |
51 | |
52 | my $options_hashref = Some::ConfigFile::Loader->load($file); |
53 | |
54 | return $options_hashref; |
55 | } |
56 | |
57 | |
58 | ######## |
59 | ## A class that uses it: |
60 | ######## |
61 | package Foo; |
62 | use Moose; |
63 | with 'MooseX::SomeSpecificConfigRole'; |
64 | |
65 | # ... insert your stuff here ... |
66 | |
67 | ######## |
68 | ## A script that uses the class with a configfile |
69 | ######## |
70 | |
71 | my $obj = Foo->new_with_config(configfile => '/etc/foo.yaml', other_opt => 'foo'); |
72 | |
73 | =head1 DESCRIPTION |
74 | |
75 | This is an abstract role which provides an alternate constructor for creating |
76 | objects using parameters passed in from a configuration file. The |
77 | actual implementation of reading the configuration file is left to |
78 | concrete subroles. |
79 | |
80 | It declares an attribute C<configfile> and a class method C<new_with_config>, |
81 | and requires that concrete roles derived from it implement the class method |
82 | C<get_config_from_file>. |
83 | |
84 | L<MooseX::Getopt> knows about this abstract role, and will use it if available |
85 | to load attributes from the file specified by the commandline flag C<--configfile> |
86 | during its normal C<new_with_options>. |
87 | |
88 | =head1 Attributes |
89 | |
90 | =head2 configfile |
91 | |
92 | This is a L<Path::Class::File> object which can be coerced from a regular pathname |
93 | string. This is the file your attributes are loaded from. |
94 | |
95 | =head1 Class Methods |
96 | |
97 | =head2 new_with_config |
98 | |
99 | This is an alternate constructor, which knows to look for the C<configfile> option |
100 | in its arguments and use that to set attributes. It is much like L<MooseX::Getopts>'s |
101 | C<new_with_options>. Example: |
102 | |
103 | my $foo = SomeClass->new_with_config(configfile => '/etc/foo.yaml'); |
104 | |
105 | Explicit arguments will overide anything set by the configfile. |
106 | |
107 | =head2 get_config_from_file |
108 | |
109 | This class method is not implemented in this role, but it is required of all subroles. |
110 | Its two arguments are the classname and the configfile, and it is expected to return |
111 | a hashref of arguments to pass to C<new()>. |
112 | |
113 | =head2 meta |
114 | |
115 | The Moose meta stuff, included here because otherwise pod tests fail sometimes |
116 | |
117 | =head1 BUGS |
118 | |
119 | =head1 AUTHOR |
120 | |
121 | Brandon L. Black, E<lt>blblack@gmail.comE<gt> |
122 | |
123 | =head1 LICENSE |
124 | |
125 | This library is free software; you can redistribute it and/or modify |
126 | it under the same terms as Perl itself. |
127 | |
128 | =cut |