/ 
Config-Fast-1.04
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/ Config::Fast

NAME

Config::Fast - extremely fast configuration file parser

SYNOPSIS

# config file is simple space-separated format
company     Supercool, Inc.
support     nobody@nowhere.com


# and then in Perl
use Config::Fast;

%cf = fastconfig;

print "Thanks for visiting $cf{company}!\n";
print "Please contact $cf{support} for support.\n";

COMPATIBILITY

Please note: Starting with the 1.04 release, all variables are now matched case-insensitively, and returned in all lowercase in the hash returned from fastconfig(). If you were using MixedCase variables, you will have to change your code to access these as $cf{mixedcase} from now on.

DESCRIPTION

This module is designed to provide an extremely fast and lightweight way to parse moderately complex configuration files. As such, it exports a single function - fastconfig() - and does not provide any OO access methods. Still, it is fairly full-featured.

Here's how it works:

%cf = fastconfig($file, $delim);

Basically, the fastconfig() function returns a hash of keys and values based on the directives in your configuration file. By default, directives and values are separated by whitespace in the config file, but this can be easily changed with the delimiter argument (see below).

When the configuration file is read, its modification time is first checked and the results cached. On each call to fastconfig(), if the config file has been changed, then the file is reread. Otherwise, the cached results are returned automatically. This makes this module great for mod_perl based modules and scripts, one of the primary reasons I wrote it. Simply include this at the top of your script or inside of your constructor function:

my %cf = fastconfig('/path/to/config/file.conf');

If the file argument is omitted, then fastconfig() looks for a file named $0.conf in the ../etc directory relative to the executable. For example, if you ran:

/usr/local/bin/myapp

Then fastconfig() will automatically look for:

/usr/local/etc/myapp.conf

This is great if you're really lazy and always in a hurry, like I am.

If this doesn't work for you, simply supply a filename manually. Note that filename generation does not work in mod_perl, so you'll need to supply a filename manually.

FILE FORMAT

By default, your configuration file is split up on the first white space it finds. Subsequent whitespace is preserved intact - quotes are not needed. For example, this:

company     Hardwood Flooring Supplies, Inc.

Would result in:

$cf{company} = 'Hardwood Flooring Supplies, Inc.';

Of course, you can use the delimiter argument to change the delimiter to anything you want, perhaps to read Bourne shell style files:

%cf = fastconfig($file, '=');

This would let you read a file of the format

system=Eunice
kernel=sortof

Each configuration directive is read sequentially and placed in the hash. If the same directive is present multiple times, the last one will override any earlier ones.

In addition, you can reuse previously-defined variables by preceding them with a $ sign. Hopefully this seems logical to you.

owner       Bill Johnson
company     $owner and Company, Ltd.

Of course, you can include literal characters by escaping them:

price       \$5.00
streetname  "Guido \"The Enforcer\" Scorcese"

Unlike previous versions of this module, variable names are case-insensitive. In this situation, the last setting of ORACLE_HOME will win:

oracle_home /oracle
Oracle_Home /oracle/orahome1
ORACLE_HOME /oracle/OraHome2

However, variables are converted to lowercase before being returned from fastconfig(), meaning you would access this as:

print $cf{oracle_home};     # /oracle/OraHome2

Speaking of which, an extra nicety is that this module will setup environment variables for any ALLCAPS variables you define. So, the above ORACLE_HOME variable will automatically be stuck into %ENV. But you would still access it in your program as oracle_home. This may seem confusing at first, but once you use it, I think you'll find it makes sense.

Finally, if called in a scalar context, then variables will be imported directly into the main:: namespace, just like if you had defined them yourself:

use Config::Fast;

fastconfig('web.conf');

print "The web address is: $website\n";     # website from conf

Generally, this is regarded as dangerous and bad form, so I would strongly advise using this form only in throwaway scripts, or not at all.

NOTES

Variables starting with a leading underscore are considered reserved and should not be used in your config file, unless you enjoy painfully mysterious behavior.

There are some global variables that you can use to customize certain aspects of this module. If you really want to tweak it, read through the source, then do something like:

use Config::Fast;
$Config::Fast::SOMESETTING = 'whatever';
%cf = fastconfig;

For a much more full-featured config module, check out Config::ApacheFormat. It can handle Apache style blocks, array values, etc, etc. This one is supposed to be fast and easy.

VERSION

$Id: Fast.pm,v 1.4 2003/11/03 21:42:12 nwiger Exp $

AUTHOR

Copyright (c) 2002-2003 Nathan Wiger <nate@sun.com>. All Rights Reserved.

This module is free software; you may copy this under the terms of the GNU General Public License, or the Artistic License, copies of which should have accompanied your Perl kit.