Config::General::Match - Add <Location> and <LocationMatch> style matching to Config::General
Version 0.05
This module is obsolete and has now been superceded by the Config::Context manpage.
use Config::General::Match;
my $config_text = '
<Location /users>
title = "User Area"
</Location>
<LocationMatch \.*(jpg|gif|png)$>
image_file = 1
</Location>
';
my $conf = Config::General::Match->new(
-String => $config_text,
-MatchSections => [
{
-Name => 'Location',
-MatchType => 'path',
},
{
-Name => 'LocationMatch',
-MatchType => 'regex',
},
],
);
my %config = $conf->getall_matching('/users/~mary/index.html');
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'title' => 'User Area',
'image_file' => undef,
};
my %config = $conf->getall_matching('/users/~biff/images/flaming_logo.gif');
print Dumper(\%config);
$VAR1 = {
'title' => 'User Area',
'image_file' => 1,
};
This module extends Config::General by providing support for
configuration sections that match only for a particular file or path or
URL.
Typically you would use this to support the Apache-style conditional blocks, for instance:
<FilesMatch .jpg$>
# ... some configuration ...
</FilesMatch>
<Location /users>
# ... some configuration ...
</Location>
<LocationMatch .html$>
# ... some configuration ...
</LocationMatch>
To read the configuration use $conf->getall_matching instead of
$conf->getall:
my $conf = Config::General::Match->new(...);
my %config = $conf->getall_matching('/users/joe/index.html');
my %other_config = $conf->getall_matching('/images/banner.jpg');
The Match feature is general enough that you can use it to match other
things besides paths and URLs. For instance you could specify a
-PathSeparator of :: and use the feature to match against Perl
modules:
my $config_text = "
is_core_module 0
<Module NET::FTP>
is_core_module 1
author Nathan Torkington
</Module>
<Module NET::FTPServer>
author Richard Jone
</Module>
";
my $conf = Config::General::Match->new(
-String => $config_text,
-MatchSections => [
{
-Name => 'Module',
-PathSeparator => '::',
-MatchType => 'path',
},
],
);
my %config = $conf->getall_matching('Net::FTP');
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'is_core_module' => 1,
'author' => 'Nathan Torkington',
};
Config values that appear outside of any block act like defaults. Values in matching sections are merged with the default values. For instance:
private_area = 0
client_area = 0
<Location /admin>
private_area = 1
</Location>
<Location /clients>
client_area = 1
</Location>
# Admin Area URL
my %config = $conf->getall_matching('/admin/index.html');
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'private_area' => 1,
'client_area' => 0,
};
# Client Area URL
my %config = $conf->getall_matching('/clients/index.html');
print Dumper(\%config);
$VAR1 = {
'private_area' => 0,
'client_area' => 1,
};
# Neither Client nor Admin
my %config = $conf->getall_matching('/public/index.html');
print Dumper(\%config);
$VAR1 = {
'private_area' => 0,
'client_area' => 0,
};
Sections and subsections are merged along with single values. For instance:
private_area = 0
client_area = 0
<page_settings>
title = "The Widget Emporium"
logo = logo.gif
advanced_ui = 0
</page_settings>
<Location /admin>
private_area = 1
<page_settings>
title = "The Widget Emporium - Admin Area"
logo = admin_logo.gif
advanced_ui = 1
</page_settings>
</Location>
<Location /clients>
client_area = 1
<page_settings>
title = "The Widget Emporium - Wholesalers"
logo = client_logo.gif
</page_settings>
</Location>
# Admin Area URL
my %config = $conf->getall_matching('/admin/index.html');
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'page_settings' => {
'advanced_ui' => '1',
'title' => 'The Widget Emporium - Admin Area',
'logo' => 'admin_logo.gif'
},
'private_area' => '1',
'client_area' => '0'
};
# Client Area URL
my %config = $conf->getall_matching('/clients/index.html');
print Dumper(\%config);
$VAR1 = {
'page_settings' => {
'advanced_ui' => '0',
'title' => 'The Widget Emporium - Wholesalers',
'logo' => 'client_logo.gif'
},
'client_area' => '1',
'private_area' => '0'
};
# Neither Client nor Admin
my %config = $conf->getall_matching('/public/index.html');
print Dumper(\%config);
$VAR1 = {
'page_settings' => {
'advanced_ui' => '0',
'title' => 'The Widget Emporium',
'logo' => 'logo.gif'
},
'client_area' => '0',
'private_area' => '0'
};
Often more than one section will match the target string. When this
happens, the matching sections are merged together using the
Hash::Merge module. Typically this means that sections that are
merged later override the values set in earlier sections. (But you can
change this behaviour. See Changing Hash::Merge behaviour below.)
The order of merging matters. The sections are merged first according
to each section's -MergePriority value (lowest values are merged
first), and second by the length of the substring that matched (shortest
matches are merged first). If you don't specify -MergePriority for
any section, they all default to a priority of 0 which means all
sections are treated equally and matches are prioritized based soley on
the length of the matching strings.
The order of sections in the config file is ignored.
For instance, if your config file looks like this:
<Dir /foo/bar/baz>
# section 1
</Dir>
<Path /foo>
# section 2
</Path>
<Dir /foo/bar>
# section 3
</Dir>
<Directory /foo/bar/baz/bam>
# section 4
</Directory>
...and you construct your $conf object like this:
my $conf = Config::General::Match->new(
-MatchSections => [
{ -Name => 'Directory', -MatchType => 'path' -MergePriority => 1 },
{ -Name => 'Dir', -MatchType => 'path' -MergePriority => 1 },
{ -Name => 'Path', -MatchType => 'path' -MergePriority => 2 },
],
);
...then the target string '/foo/bar/baz/bam/boom' would match all sections the order of 1, 3, 4, 2.
Creates and returns a new Config::General::Match object.
my $conf = Config::General::Match->new(
-MatchSections => [
{ -Name => 'Directory', -MatchType => 'path' },
],
-ConfigFile => 'somefile.conf',
);
The arguments to new() are the same as you would provide to
Config::General, with the addition of -MatchSections. (But see
see the BUGS section for limitations on compatibility with
Config::General.)
The -MatchSections parameter takes a list of specification hashrefs.
Each specification has the following fields:
The name of the section. For a name of 'Location', the section would look like:
<Location /somepath>
</Location>
This parameter is affected by the Config::General option
-LowerCaseNames. If -LowerCaseNames is true, then the following
would all be valid 'Location' sections.
<Location /somepath>
</Location>
<loCATtion /somepath>
</Location>
<lOcAtion /somepath>
</LOCATION>
Specifies the method by which the section strings should match the target string.
The valid types of matches are 'exact', 'substring', 'regex', 'path', and 'hierarchical'
The config section string matches only if it is equal to the target string. For instance:
# somefile.conf
<Site mysite>
...
</Site>
...
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'Site',
-MatchType => 'exact',
},
],
-ConfigFile => 'somefile.conf',
);
In this case, only the string mysite would match the section.
The config section string is tested to see if it is a substring of the target string. For instance:
# somefile.conf
<Location foo>
...
</Location>
...
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'LocationMatch',
-MatchType => 'substring',
},
],
-ConfigFile => 'somefile.conf',
);
In this case, the following target strings would all match:
/foo
big_foo.html
/hotfood
Do not quote the match string; it will not work if you do so.
The config section string is treated as a regular expression against which the target string is matched. For instance:
# somefile.conf
<LocationMatch (\.jpg)|(\.gif)(\.png)$>
Image = 1
</LocationMatch>
...
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'LocationMatch',
-MatchType => 'regex',
},
],
-ConfigFile => 'somefile.conf',
);
my %config = $conf->getall_matching('banner.jpg');
The regex can contain any valid Perl regular expression. So to match
case-insensitively you can use the (?i:) syntax:
<LocationMatch (?i:/UsErS)>
UserDir = 1
</LocationMatch>
Also note that the regex is not tied to the beginning of the target string by default. So for regexes involving paths you will probably want to do so explicitly:
<LocationMatch ^/users>
UserDir = 1
</LocationMatch>
Do not quote a regex; it will not work if you do so.
This method is useful for matching paths, URLs, Perl Modules and other hierarchical strings.
The config section string is tested against the the target string according to the following rules:
The section string is a substring of the target string
The section string starts at the first character of the target string
In the target string, the section string is followed immediately by
-PathSeparator or the end-of-string.
For instance:
# somefile.conf
<Location /foo>
</Location>
...
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'LocationMatch',
-MatchType => 'path',
},
],
-ConfigFile => 'somefile.conf',
);
In this case, the following target strings would all match:
/foo
/foo/
/foo/bar
/foo/bar.txt
But the following strings would not match:
/foo.txt
/food
/food/bar.txt
foo.txt
Do not quote the path; it will not work if you do so.
A synonym for 'path'.
The path separator when matching hierarchical strings (paths, URLs, Module names, etc.). It defaults to '/'.
This parameter is ignored unless the -MatchType is 'path' or
'hierarchical'.
Allows you to only process certain sections for certain types of strings. For instance, you could match some sections against a given filesystem path and some sections against a Perl module name, using the same config file.
# somefile.conf
# section 1
<FileMatch \.pm$>
Perl_Module = 1
Core_Module = 1
Installed_Module = 0
</FileMatch>
# section 2
<FileMatch ^/.*/lib/perl5/site_perl>
Core_Module = 0
</FileMatch>
# section 3
# Note the whitespace at the end of the section name, to prevent File from
# being parsed as a stand-alone block by Config::General
<File /usr/lib/perl5/ >
Installed_Module = 1
</File>
# section 4
<Module NET::FTP>
FTP_Module = 1
</Module>
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'FileMatch',
-MatchType => 'regex',
-SectionType => 'file',
},
{
-Name => 'File',
-MatchType => 'path',
-SectionType => 'file',
},
{
-Name => 'Module',
-MatchType => 'path',
-Separator => '::',
-SectionType => 'module',
},
],
-ConfigFile => 'somefile.conf',
# need to turn off C-style comment parsing because of the
# */ in the name of section 3
-CComments => 0,
);
my %config = $conf->getall_matching(
file => '/usr/lib/perl5/site_perl/5.6.1/NET/FTP/Common.pm',
module => 'NET::FTP::Common',
);
This tests /usr/lib/perl5/site_perl/5.6.1/NET/FTP/Common.pm against
sections 1, 2 and 3 (and merging them in the order of shortest to
longest match, i.e. 1, 3, 2).
Then it tests 'NET::FTP::Common' against section 4 (which also matches). The resulting configuration is:
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'Perl_Module' => 1,
'Core_Module' => 0,
'FTP_Module' => 1,
'Installed_Module' => 1,
};
Another example:
my %config = $conf->getall_matching(
file => '/var/www/cgi-lib/FTP/FTPServer.pm',
module => 'NET::FTPServer',
);
This tests /var/www/cgi-lib/NET/FTPServer.pm against sections 1, 2
and 3, and matches only against section 1. Then it matches
'NET::FTPServer' against section 4 (which does not match). The
result is:
use Data::Dumper;
print Dumper(\%config);
$VAR1 = {
'Perl_Module' => 1,
'Core_Module' => 0,
'FTP_Module' => 0,
'Installed_Module' => 0,
};
If a -SectionType is not specified in a -MatchSections block, then
target strings of a named type will not match it.
Matching by -SectionType is used in
CGI::Application::Plugin::Config::General to generate configurations
based both on the URL of the request and of the name of the Perl Module
and runmode handling the request.
By default, section names are trimmed of leading and trailing whitespace before they are used to match. This is to allow for sections like:
<Path /foo/bar/ >
</Path>
The whitespace at the end of the section name is necessary to prevent
Config::General's parser from thinking that the first tag is an empty
<Path /> block.
<Path /foo/bar/> # Config::General parses this as <Path />
</Path> # Config::General now considers this to be spurious
If leading and trailing whitespace is significant to your matches, you
can disable trimming by setting -TrimSectionNames to 0 or undef.
Sections with a lower -MergePriority are merged before sections with
a higher -MergePriority. If two or more sections have the same
-MergePriority they are weighted the same and they are merged
according to the "best match" against the target string (i.e. the
longest matching substring).
See the description above under Merging Multiple Matching Sections.
Config::General::Match is a subclass of Config::General, so you
can use of Config::General's methods. In particular, you can use
getall() to get the entire configuration without concern for any
section matching.
Returns the merged configuration of all sections matching
$target_string, according to the rules set up in the
-MatchSections in new(). All -MatchSections are included,
regardless of their -SectionType.
Returns the merged configuration matching $target_string, based only
the -MatchSections that have a -SectionType of $type.
Returns the merged configuration of all sections of -SectionType
$type1 matching $target_string1 and all sections of
-SectionType $type2 matching $target_string2.
The order of the parameters to getall_matching() is retained, so
$type1 sections will be matched first, followed by $type2
sections.
If you call getall_matching in a scalar context, you will receive a
reference to the config hash:
my $config = $conf->getall_matching($target_string);
my $value = $config->{'somekey'};
Behaves the same as getall_matching, except that it can match nested
structures.
# stories.conf
<Story Three Little Pigs>
antagonist = Big Bad Wolf
moral = obey the protestant work ethic
</Story>
<Location /aesop>
<Story Wolf in Sheep's Clothing>
antagonist = Big Bad Wolf
moral = appearances are deceptive
</Story>
</Location>
<Story Little Red Riding Hood>
antagonist = Big Bad Wolf
<Location /perrault>
moral = never talk to strangers
</Location>
<Location /grimm>
moral = talk to strangers and then chop them up
</Location>
</Story>
my $conf = Config::General::Match->new(
-MatchSections => [
{
-Name => 'Story',
-MatchType => 'substring',
-SectionType => 'story',
},
{
-Name => 'Location',
-MatchType => 'path',
-SectionType => 'path',
},
],
-ConfigFile => 'stories.conf',
);
my $depth = 2;
$config = $conf->getall_matching_nested(
$depth,
story => 'Wolf in Sheep\'s Clothing',
path => '/aesop/wolf-in-sheeps-clothing',
);
use Data::Dumper;
print Dumper($config);
$VAR1 = {
'antagonist' => 'Big Bad Wolf',
'moral' => 'appearances are deceptive'
};
Matching sections are merged together using the Hash::Merge module.
If you want to change how this module does its work you can call
subroutines in the Hash::Merge package directly. For instance, to
change the merge strategy so that earlier sections have precidence over
later sections, you could call:
# Note American Spelling :)
Hash::Merge::set_behavior('RIGHT_PRECEDENT')
You should do this before you call getall_matching().
For more information on how to change merge options, see the
Hash::Merge docs.
Michael Graham, <mag-perl@occamstoothbrush.com>
This module does not support the functional interface to
Config::General (e.g. ParseConfig()).
This module only supports the following constructor form:
my $self = Config::General::Match->new( %options );
It does not support the other two Config::General constructor styles:
# NOT supported
my $self = Config::General->new( "rcfile" );
my $self = Config::General->new( \%some_hash );
Please report any bugs or feature requests to
bug-config-general-match@rt.cpan.org, or through the web interface at
http://rt.cpan.org. I will be notified, and then you'll automatically
be notified of progress on your bug as I make changes.
Config::General
CGI::Application::Plugin::Config::General
Hash::Merge
This module would not be possible without Thomas Linden's excellent
Config::General module.
Copyright 2004-2005 Michael Graham, All Rights Reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.