Config::MVP::Reader - object to read config from storage into an assembler
version 2.200013
use Config::MVP::Reader::YAML; # this doesn't really exist
my $reader = Config::MVP::Reader::YAML->new;
my $sequence = $reader->read_config('/etc/foobar.yml');
A Config::MVP::Reader exists to read configuration data from storage (like a
file) and convert that data into instructions to a Config::MVP::Assembler,
which will in turn convert them into a Config::MVP::Sequence, the final
product.
This module should work on any version of perl still receiving updates from the
Perl 5 Porters. This means it should work on any version of perl released in
the last two to three years. (That is, if the most recently released version
is v5.40, then this module should work on both v5.40 and v5.38.)
Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased. The version may be increased
for any reason, and there is no promise that patches will be accepted to lower
the minimum required perl.
If true (which it is by default) then the current working directly will be
locally added to @INC during config loading. This helps deal with changes made
in Perl v5.26.1.
my $sequence = $reader->read_config($location, \%arg);
This method is passed a location, which has no set meaning, but should be the
mechanism by which the Reader is told how to locate configuration. It might be
a file name, a hashref of parameters, a DBH, or anything else, depending on
the needs of the specific Reader subclass.
It is also passed a hashref of arguments, of which there is only one valid
argument:
assembler - the Assembler object into which to read the config
If no assembler argument is passed, one will be constructed by calling the
Reader's "build_assembler" method.
Subclasses should generally not override "read_config", but should
instead implement a "read_into_assembler" method, described below.
If a subclass
does override "read_config" it should take care
to respect the "add_cwd_to_lib" attribute, above.
This method should not be called directly. It is called by
"read_config" with the following parameters:
my $sequence = $reader->read_into_assembler( $location, $assembler );
The method should read the configuration found at $location and use it to
instruct the $assembler (a Config::MVP::Assembler) what configuration to
perform.
The default implementation of this method will throw an exception complaining
that it should have been implemented by a subclass.
If no Assembler is provided to "read_config"'s "assembler"
parameter, this method will be called on the Reader to construct one.
It must return a Config::MVP::Assembler object, and by default will return an
entirely generic one.
Ricardo Signes <
[email protected]>
This software is copyright (c) 2022 by Ricardo Signes.
This is free software; you can redistribute it and/or modify it under the same
terms as the Perl 5 programming language system itself.