Hustle::Table - Cached general purpose dispatch and routing table
use Hustle::Table;
Create a new table:
my $table=Hustle::Table->new;
Add entry as hash ref:
$table->add( { matcher => qr/regex (match)/, value=> "a value"});
Add entry as array ref (3 elements required):
$table->add( [qr/another/, "another value", undef])
Add entry as flat key value pairs:
$table->add(matcher=>"jones", value=> sub {"one more"}, type=>"begin");
Add entry as tuple
$table->add(qr|magic matcher| => "to a value");
Set the default entry:
$table->set_default("default value");
Prepare a dispatcher external cache:
my %cache; my $dispatch = $table->prepare_dispatcher(cache=>\%cache);
Call dispatcher to return the matching entry and any regex captures
my ($entry, $captures)=$dispatch->("thing to match");
This module provides a class to construct a routing table and build a high performance dispatcher from it.
A table can have any combination of regex, exact string, begin string end string or numeric matching of entries. The order in which the entries are added defines their precedence. First in, first tested.
In the case of no entries matching the input, a default/fallback entry always matches.
Once all the entries have been added to the table, a dispatcher is prepared/created. The dispatcher is an anonymous subroutine, which tests its argument against the matcher in each entry in the table.
It returns a list containing the first entry that matched, and an anonymous array of any captures from regex matching.
If more entries are required to be added to the table, the dispatcher must be prepared again.
A cache (hash) is used to drastically improve table lookup performance. Entries are automatically added to the cache. However removal of cache entries is up to the user to implement on a application basis.
Calling the class constructor returns a new table. There are no required arguments:
In this case, a default catch all entry (an undef value) is added automatically.
If an argument is provided, it is the value used in the default/catch all entry:
my $table=Hustle::Table->new($default);
An entry is an anonymous array containing the following elements:
[matcher, value, type, default]
matcher can be a regex, a string or a numeric value.
matcher
When matcher is a regex, any captures are returned as the second item when calling the dispatcher
When matcher is string or numeric value, the last field type specifies how to perform the match. See type below.
type
If no type is specified or is undef, the matcher is always treated as a regex
undef
This is the data you want to retrieve from the table when the matches.
type is used to adjust how the matcher is interpreted. The possible values are:
undef => matcher is always treated as a regex "begin" => matches the begining of input string "end" => matches the end of input string "exact" => string equality "numeric" => numeric equality
If matcher is a precompiled regex (i.e. qr{}), type is ignored.
qr{}
If matcher is a string or number, it is treated as a regex unless type is as above.
This is a flag indicating if the entry was the default entry
Entries are added in anonymous hash, anonymous array or flattened format, using the add method.
add
Anonymous array entries must contain six elements, in the order of:
$table->add([$matcher, $value, $type]);
Anonymous hashes format only need to specify the matcher and value pairs
$table->add({matcher=>$matcher, value=>$value, type=>$type});
Single flattened format takes a list directly. It must contain 4 elements
$table->add(matcher=>$matcher, value=> $value);
Single simple format takes two elements
$table->add(qr{some matcher}=>$value);
Or add multiple at once using mixed formats together
$table->add( [$matcher, $value, $type], {matcher=> $matcher, value=>$value}, matcher=>$matcher, value=>$value );
In any case,matcher and value are the only items which must be defined.
value
Each list has a default matcher that will unconditionally match the input. This entry is specified by using undef as the matcher when adding an entry. When set this way only the array format can be used.
To make it more explicit, the it can also be changed via the set_default method.
set_default
The default value of the 'default' entry is undef
Once all the entries are added to the table, the dispatcher can be constructed by calling prepare_dispatcher:
prepare_dispatcher
my $dispatcher=$table->prepare_dispatcher(%args);
Arguments to this method include:
The hash ref to use as the dispatchers cache. Specifying a hash allows external management. If no cache is specified an internal cache is used.
The dispatcher is simply a sub, which you call with the input to match against the table entries:
my ($entry, $captures)=$dispatcher->("input"); my $value=$entry->[1];
The return from the dispatcher is a list of two elements.
The first is the array reference to the table entry that matched (or the default entry if no match was found). The value associated with the table entry is located in position 1
The second item returned is an anonymous array of any captures due to a matching regex
Solid performance compared to other perl routing/dispatch modules. Faster in basic tests then other perl modules:
Smart::Dispatch Router::Simple Router::Boom
If you need even more performance then checkout URI::Router
TODO: make proper benchmark and comparison
Ruben Westerberg, <drclaw@mac.com>
Copyright (C) 2022 by Ruben Westerberg
Licensed under MIT
THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
To install Hustle::Table, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Hustle::Table
CPAN shell
perl -MCPAN -e shell install Hustle::Table
For more information on module installation, please visit the detailed CPAN module installation guide.