redisque

About

Redisque is yet another lightweight and simple to use queue manager with Redis DB backend. Installation

Run $ sudo gem install redisque How to use

Redisque has only three methods that you will employ:

Redisque.connect(options)

with the help of this method you can customize your connection to Redis DB. options is a Hash and can have the keys: :address, :port, :password and :db.

Redisque.enqueue(queue, data) 

makes possible to add task represented by data (Hash) to queue (String).

Redisque.workoff(queue, pause = 5, &block) 

manages the queue: asks the queue for the next entry (job that is represented with JSONized Hash) and if it gets one then the block is executed with data received otherwise sleep for pause time set in seconds, this way we give a chance to another processes to do their job :)

Usage scenario might look like:

in your application:

require "redisque"
[
  {:id => 1, :city => 'New York'},
  {:id => 2, :city => 'Pekin'},
  {:id => 3, :city => 'Mumbai'},
  {:id => 4, :city => 'Paris'},
  {:id => 5, :city => 'Madrid'}
].each {|chunk| Redisque.enqueue('my_queue', chunk)}

in your [Worker] *.rb file:

require "redisque"
Redisque.connect(:password => 'secret')
Redisque.workoff('my_queue') do |data|
   puts "Next city is: %s" % data["city"]
end

Halting Redisque:

Redisque has a key halting and you can use it to halt the execution, i.e. in your [Worker] *.rb file:

trap('INT')  do
  print "1. (Q)uit now\n2. (W)ait for current task to finish\n3. (C)ontinue\n"  
  case gets.chomp
  when 'Q'
    exit
  when 'W'
    Redisque.halting = true
    print 'Redisque instance resumes until current Job is finished'
  else    
  end
end
trap('TERM') {exit}

require "json"
require "redisque"

...

Caution

Redisque creates backup queue when it's run with the following name convention:

original queue name that is preceded with asterisk symbol

e.g. if your queue name was my_queue then the backup queue name would be *my_queue so you should keep it in mind when working with other queues that some names are already automatically reserved for backup queues

In case Worker was interrupted, backup queue data (if any) will be shifted into active queue on next Worker start, thus if task was running but didn't succeed, it's entry will be restored from backup queue. For your Worker to function properly it has to be able to redo all steps regardless the execution moment it was stopped at.

Contribute to project

Please do.

If you feel that it lacks some functionality or enhancement or anything else, please feel free to:

• clone the project
• create a branch do your changes or improvements in it and
• make a pull request

to review code and merge the branch.

Thank you

License

MIT License

Copyright (c) 2012 Yuri Belogub

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.