NAME¶
ConfigReader::Simple - A simple line-oriented configuration file parser
SYNOPSIS¶
use ConfigReader::Simple;
# parse one file
$config = ConfigReader::Simple->new("configrc", [qw(Foo Bar Baz Quux)]);
# parse multiple files, in order
$config = ConfigReader::Simple->new_multiple(
Files => [ "global", "configrc" ],
Keys => [qw(Foo Bar Baz Quux)]
);
my @directives = $config->directives;
$config->get( "Foo" );
if( $config->exists( "Bar" ) ) {
print "Bar was in the config file\n";
}
# copy an object to play with it separately
my $clone = $config->clone;
# only affects clone
$clone->set( "Foo", "Buster" );
# save the config to a single file
$clone->save( "configrc" )
# save the config to a single file, but only with
# certain directives
$clone->save( "configrc" => [qw(Foo Bar)] )
# save to multiple configuration files
$clone->save(
"configrc" => [qw(Foo Bar)],
"global" => [qw(Baz Quux)],
);
DESCRIPTION¶
"ConfigReader::Simple" reads and parses simple configuration files. It
is designed to be smaller and simpler than the "ConfigReader" module
and is more suited to simple configuration files.
The configuration file uses a line-oriented format, meaning that the directives
do not have containers. The values can be split across lines with a
continuation character, but for the most part everything ends up on the same
line.
The first group of non-whitespace characters is the "directive", or
the name of the configuration item. The linear whitespace after that separates
the directive from the "value", which is the rest of the line,
including any other whitespace.
In this example, the directive is "Camel" and the value is
"Dromedary".
Camel Dromedary
Optionally, you can use a equal sign to separate the directive from the value.
Camel=Dromedary
The equal sign can also have whitespace on either or both sides.
Camel = Dromedary
Camel= Dromedary
In the next example, the directive is "Llama" and the value is
"Live from Peru"
Llama Live from Peru
This is the same, to "ConfigReader::Simple", as the following which
has more whitespace between the directive and the value.
Llama Live from Peru
You can also enclose the value in single or double quotes.
Llama "Live from Peru"
Llama 'Live from Peru'
Llama='Live from Peru'
In some cases you may want to split the logical line across two lines, perhaps
to see it better in a terminal window. For that, use a \ followed only by
whitespace. To split the last entry across two lines, we use the \ at the end
of the line. These three entries are the same:
Llama Live from Peru
Llama Live from \
Peru
Llama Live \
from \
Peru
If a line is only whitespace, or the first whitespace character is a #, the Perl
comment character, "ConfigReader::Simple" ignores the line unless it
is the continuation of the previous line.
Methods¶
- new ( FILENAME, DIRECTIVES )
- Creates a "ConfigReader::Simple" object.
"FILENAME" tells the instance where to look for the configuration
file. If FILENAME cannot be found, an error message for the file is added
to the %ERROR hash with the FILENAME as a key, and a combined error
message appears in $ERROR.
"DIRECTIVES" is an optional argument and is a reference to an
array. Each member of the array should contain one valid directive. A
directive is the name of a key that must occur in the configuration file.
If it is not found, the method croaks. The directive list may contain all
the keys in the configuration file, a sub set of keys or no keys at all.
The "new" method is really a wrapper around
"new_multiple".
- new_multiple( Files => ARRAY_REF, Keys => ARRAY_REF )
- Create a configuration object from several files listed in the anonymous
array value for the "Files" key. The module reads the files in
the same order that they appear in the array. Later values override
earlier ones. This allows you to specify global configurations which you
may override with more specific ones:
ConfigReader::Simple->new_multiple(
Files => [ qw( /etc/config /usr/local/etc/config /home/usr/config ) ],
);
This function croaks if the values are not array references.
If this method cannot read a file, an error message for that file is added
to the %ERROR hash with the filename as a key, and a combined error
message appears in $ERROR. Processing the list of filenames continues if a
file cannot be found, which may produced undesired results. You can
disable this feature by setting the $ConfigReader::Simple::Die variable to
a true value.
- new_string( Strings => ARRAY_REF, Keys => ARRAY_REF )
- Create a configuration object from several strings listed in the anonymous
array value for the "Strings" key. The module reads the strings
in the same order that they appear in the array. Later values override
earlier ones. This allows you to specify global configurations which you
may override with more specific ones:
ConfigReader::Simple->new_strings(
Strings => [ \$global, \$local ],
);
This function croaks if the values are not array references.
- add_config_file( FILENAME )
- Parse another configuration file and add its directives to the current
configuration object. Any directives already defined will be replaced with
the new values found in FILENAME.
- files
- Return the list of configuration files associated with this object. The
order of the return values is the order of parsing, so the first value is
the first file parsed (and subsequent files may mask it).
- new_from_prototype(
- Create a clone object. This is the same thing as calling
clone().
- parse( FILENAME )
- This does the actual work.
This is automatically called from "new()", although you can
reparse the configuration file by calling "parse()" again.
- parse_string( SCALAR_REF )
- Parses the string inside the reference SCALAR_REF just as if it found it
in a file.
- get( DIRECTIVE )
- Returns the parsed value for that directive. For directives which did not
have a value in the configuration file, "get" returns the empty
string.
- set( DIRECTIVE, VALUE )
- Sets the value for DIRECTIVE to VALUE. The DIRECTIVE need not already
exist. This overwrites previous values.
The VALUE must be a simple scalar. It cannot be a reference. If the VALUE is
a reference, the function prints a warning and returns false.
- unset( DIRECTIVE )
- Remove the value from DIRECTIVE, which will still exist. It's value is
undef. If the DIRECTIVE does not exist, it will not be created. Returns
FALSE if the DIRECTIVE does not already exist, and TRUE otherwise.
- remove( DIRECTIVE )
- Remove the DIRECTIVE. Returns TRUE is DIRECTIVE existed and FALSE
otherwise.
- directives()
- Returns a list of all of the directive names found in the configuration
file. The keys are sorted ASCII-betically.
- exists( DIRECTIVE )
- Return TRUE if the specified directive exists, and FALSE otherwise.
- clone
- Return a copy of the object. The new object is distinct from the original
so you can make changes to the new object without affecting the old
one.
- save( FILENAME [ => ARRAY_REF [, FILENAME => ARRAY_REF ] ] );
- The save method works in three ways, depending on the argument list.
With a single argument, the save function attempts to save all of the
field-value pairs of the object to the file named by the argument.
$clone->save( "configrc" );
With two arguments, the method expects the second argument to be an array
reference which lists the directives to save in the file.
$clone->save( "configrc" => [qw(Foo Bar)] );
With more than two arguments, the method expects filename-list pairs. The
method will save in each file the values in their respective array
references.
$clone->save(
"configrc" => [qw(Foo Bar)],
"global" => [qw(Baz Quux)],
);
In the last two cases, the method checks that the value for each pair is an
array reference before it affects any files. It croaks if any value is not
an array reference.
Once the method starts writing files, it tries to write all of the specified
files. Even if it has a problem with one of them, it continues onto the
next one. The method does not necessarily write the files in the order
they appear in the argument list, and it does not check if you specified
the same file twice.
Package variables¶
- $Die - DEPRECATED
- If set to a true value, all errors are fatal.
- $ERROR
- The last error message.
- %ERROR
- The error messages from unreadable files. The key is the filename and the
value is the error message.
- $Warn - DEPRECATED
- If set to a true value, methods may output warnings.
LIMITATIONS/BUGS¶
Directives are case-sensitive.
If a directive is repeated, the first instance will silently be ignored.
CREDITS¶
Bek Oberin "<gossamer@tertius.net.au>" wote the original module
Kim Ryan "<kimaryan@ozemail.com.au>" adapted the module to make
declaring keys optional. Thanks Kim.
Alan W. Jurgensen "<jurgensen@berbee.com>" added a change to
allow the NAME=VALUE format in the configuration file.
Andy Lester, "<petdance@cpan.org>", for maintaining the module
while brian was on active duty.
Adam Trickett, "<atrickett@cpan.org>", added multi-line support.
You might want to see his "Config::Trivial" module.
Greg White has been a very patient user and tester.
SOURCE AVAILABILITY¶
The source is in Github:
http://github.com/briandfoy/ConfigReader-Simple/tree/master
AUTHORS¶
brian d foy, "<bdfoy@cpan.org>"
COPYRIGHT AND LICENSE¶
Copyright (c) 2002-2014 brian d foy. All rights reserved.
This program is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.