NAME

Queue::Q::NaiveFIFO - Very primitive FIFO queue

SYNOPSIS

  use Queue::Q::NaiveFIFO::Redis; # or ::Perl

DESCRIPTION

Abstract interface class for a naive FIFO queue without resilience against crashing workers. Implementations are required to provide strict ordering and adhere to the run-time complexities listed below (or better).

METHODS

enqueue_item

Given a data structure, that data structure is added to the queue. Items enqueued with enqueue_item in order must be returned by claim_item in the same order.

Complexity: O(1)

enqueue_items

Given a number data structures, enqueues them in order. This is conceptually the same as calling enqueue_item multiple times, but may help save on network round-trips.

Complexity: O(n) where n is the number of items to enqueue.

claim_item

Returns the oldest item in the queue. Returns undef if there is none left.

Complexity: O(1)

claim_items

As enqueue_items is to enqueue_item, claim_items is to claim_item. Takes one optional parameter (defaults to 1): The number of items to fetch and return:

  my @items = $q->claim_items(20); # returns a batch of 20 items

If there are less than the desired number of items to be claimed, returns a correspondingly shorter list.

Complexity: O(n) where n is the number of items claimed.

queue_length

Returns the number of items available in the queue.

Complexity: O(1)

flush_queue

Removes all content in the queue.

Complexity: O(n) where n is the number of items in the queue.

AUTHOR

Steffen Mueller, <smueller@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2012 by Steffen Mueller

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or, at your option, any later version of Perl 5 you may have available.