NAME

Redis::Object - Use Redis with an ORMish interface

DESCRIPTION

Implements a scaled down ORM-like interface to access Redis as a database. If you want to use Redis as a cache, use Redis instead.

SYNOPSIS

package MyRedisDatabase;

use Moose;
extends qw/ Redis::Object /;

has tables => ( isa => 'ArrayRef[Str]', is => 'ro', default => sub { [ qw/
    SomeTable
/ ] } );

__PACKAGE__->make_immutable;

package MyRedisDatabase::SomeTable;

use Moose;
with qw/ Redis::Object::Table /;

has attrib1 => ( isa => 'Str', is => 'rw', default => 'Something' );
has attrib2 => ( isa => 'StrIndexed', is => 'rw', required => 1 );
has attrib3 => ( isa => 'StrIndexedSafe', is => 'rw', required => 1 );
has attrib4 => ( isa => 'Int', is => 'rw' );
has attrib5 => ( isa => 'HashRef', is => 'rw' );
has attrib6 => ( isa => 'ArrayRef', is => 'rw' );

__PACKAGE__->make_immutable;

package main;

# init database
my $db = MyRedisDatabase->new(
    server => '127.0.0.1:6379'
);

# create item
my $item = $db->create( SomeTable => {
    attrib1 => "Hello",
    attrib2 => "Will be indexed",
    attrib3 => "Will-too-be-indexed",
    attrib4 => 123,
    attrib5 => { something => "serializeable" },
    attrib6 => [ 1..99 ]
} );
print "Created ". $item->id;

# fetch item by id
my $item = $db->find( SomeTable => $id );
print $item->attrib1. "\n";

# search items
my $result = $db->search( SomeTable => {
    attrib1 => "Hello",
    attrib2 => 123
} );
while( my $item = $result->next ) {
    print "Found ". $item->id. "\n";
}

# update item
$item->attrib1( "bla" ); # set directly, will be persisted in the next update
$db->update( $item, { # set additonal
    attrib2 => 333
} );

$item->attrib2( 999 );
$item->update( { # call update on the item, with additional new values
    attrib1 => "Hallo"
} );

# remove an item
$db->remove( $item );
$item->remove;

# clear a table (remvoe all entries!)
$db->truncate( 'SomeTable' );

YOU SHOULD KNOW

Searching / Sorting

Redis is more than a simple key-value store - but it is no relational database, by any means. So limit your expectations towards complex searching or sorting (actually, there is no sorting at all, yet).

This interface implements searching by primary key (an integer ID, which is automatically assigened to each "row" in the database), searching indexed String values with compare- and prefix-search. All search capability aside from this results in a full "table" scan.

Indices

This interface allows you to define certain columes as indexed. Those columes have to be of the following tyhoes:

• StrIndexed

  Can contain anything you want - howver, it is not guranteed, that this index will really work in if you use special chars, which (i had no tested and) are not searchable by the wildcard-keysearch. Use on your own risk and run your own tests!

• StrIndexedSafe

  Can only contain safe characters "a".."z", "A".."Z" and 0..9. Also the length is limited to 256 characters. However, you can possibly use very long keys in redis. Also you should account for the prefix length (composed of the prefix, the table name and the attribute name). However, if you need longer contents, go with StrIndexed.

The indices can be search with a wildcard search, such as Something* or even Some*thing*.

Example

The table

package MyRedisDatabase::MyTable;

use Moose;
with qw/ Redis::Object::Table /;

has indexedkey => ( isa => "StrIndexed", is => "rw", required => 1 );
has safeindexedkey => ( isa => "StrIndexedSafe", is => "rw", required => 1 );

Using the search

$db->create( MyTable => {
    indexed => "Some content",
    safeindexedkey => "Some-safe-content"
} );
my $result = $db->search( MyTable => {
    safeindexedkey => "Some*"
} );
while( my $item = $result->next ) { .. }

Structure

This interface will store your instances, represented by Redis::Object::Table-objects, in a distinct structure. Do not try to use this interface with pre-existing data! Also modifying the data manually later on is at your own risk!

The structure relates to the Moose attributes of your classes. Assuming the following table-class:

package MyRedisDatabase::MyTable;

use Moose;
with qw/ Redis::Object::Table /;

has somekey => ( isa => "StrIndexed", is => "rw", required => 1 );
has otherkey => ( isa => "Int", is => "rw", required => 1 );

Assumnug you create an create like so:

$db->create( MyTable => {
    somekey => "Some Content",
    otherkey => 123
} );

The resulting "rows" for the entry (with the ID 999) would look something like this:

# contains the an ID timestamp, used for certain lookups
mytable:999:_ # = timestamp

# contains the values of both attributes
mytable:999:somekey #  Some Content
mytable:999:otherkey # = 123

# indexed key "somekey" for fast lookup
mytable:999:_:somekey:Some_Content # timestamp

There is also a special key/value per table, which contains an incrementing integer (the "primary key")

mytable:_id # = last id

ATTRIBUTES

server

Defaults to 127.0.0.1:6379

server_args

Additional args forwarded to the "new" in Redis method.

tables

Array of table names

prefix

Optional prefix for all key names in Redis

METHODS

new %args

%args

• server

  The Redis server and port, defaults to '127.0.0.1:6379'

• tables

  Arrayref of table names. A table has to be implemented as a perl module with the same name.

create $table_name, $create_ref

Create new item

$table_name

The name of the table

$create_ref

The attributes of the object to be created

update $item, [$update_ref]

Update existing item into database

find $table_name, $item_id

Finds a single item by id

$table_name

Name of the table

$item_id

ID of the item

search $table_name, $filter, [$args_ref]

Search multiple items by attribute filter.

You can

$table_name

Name of the table

$filter

The search condition can have multiple shapes:

SubRef

A ref to a grep-like sub. Example:

my $sub_filter = sub {
    my ( $item ) = @_;
    
    # add item to list
    return 1
        if ( $item->attribute eq "something" );
    
    # drop item
    return 0;
};

A whole table scan will be performed

HashRef

A subset of keys and value constraints, Example:

# this is an AND-filter: all constraints have to fit
my $filter_ref = {
    
    # simple string matching
    attribute1 => 'something',
    
    # string matches one
    attribute1 => 'something',
    
    # regex filter
    attribute2 => qr/^123/,
    
    # custom filter
    attribute3 => sub {
        my ( $value) = @_;
        return $value =~ /^xx/ && length( $value ) > 99;
    }
}

Searches on indexed attributes (of the type Str)

$args_ref

• or_search

  Perform an or-search instead (default: and-search)

Example

my $result = $db->search( TableName => {
    attrib => "bla"
} );
while( my $item = $result->next ) {
    # ..
}

remove $search_or_item

Remove a single or multiple items

Single usage

$db->remove( $item );

Multie usage

$db->remove( $table => $search_ref );

truncate

Empties a whole table. ID will be reset. Use with caution.

count

Returns the total amount of entries in a table.

AUTHOR

Ulrich Kautz <uk@fortrabbit.de>

COPYRIGHT

Copyright (c) 2011 the "AUTHOR" as listed above

LICENCSE

Same license as Perl itself.

cpanm Redis::Object

perl -MCPAN -e shell
install Redis::Object