lajcisvk / redbis

Simple redis wrapper to select database by name.

ReDBis - redis wrapper

• [github project] (https://github.com/geronime/redbis)

ReDBis is simple redis wrapper to select database by name. ReDBis inherits from Redis and provides some extra methods.

DB naming

Naming is done by storing {:name => :id} into 'ReDBis::databases' hash in database #0.

Usage

require 'redbis'

HiRedis

If you want to use [hiredis] (https://github.com/pietern/hiredis-rb) it is necessary to install it:

$ gem install hiredis

or include it in your Gemfile:

gem 'hiredis', '~> 0.4.0'

It will be used automatically (with fallback to plain redis in case of LoadError).

It is not included as dependency in gemspec because it does not build on all systems yet (i.e. FreeBSD).

Constructor

r = ReDBis.new(o={})

The ReDBis class inherits from Redis and accepts two constructor options on top:

• db - select database with specified name (optional, default database with id #0 is selected by default)
• create - whether to record a new database name if no such name is already registered (default false)

It is recommended not to use the database with id #0 as the information about the database names is stored there and flushdb would drop it.

Methods on top of Redis

db_current

Return {:id => <id>, :name => <name>} information about currently selected database. :name is nil if the database was selected by its id and no name is registered for it. It is always nil for db #0.

select

r.select id

ReDBis overrides original select method in order to keep the track of the currently selected database. Otherwise it is backward compatible (to select the database by its id).

db_select

r.db_select(name, create=false)

Select the database given its name.

If no such database name is already recorded:

• raise an error for create=false,
• record a new one with the lowest available db id otherwise (raise an error if all available db ids are already taken).

db_delete

r.db_delete name

Delete the database with specified name or raise an error if no such name is registered. The content of the specified database is flushed. Afterwards the previously selected database is re-selected or database with id #0 is selected if the name specified currently selected database.

db_delete!

Same as db_delete but rescue the exception raised if the specified name is not registered. Returns true/false as the database was/was not deleted.

Changelog

• 0.0.3: using optional hiredis instead of pure ruby connector
• 0.0.2: options passed to initialization method are not replaced
• 0.0.1: first revision

License

ReDBis is copyright (c)2011 Jiri Nemecek, and released under the terms of the MIT license. See the LICENSE file for the gory details.