engine/lib/locomotive/mongoid/patches.rb

91 lines
2.3 KiB
Ruby

# encoding: utf-8
require 'mongoid'
# Limit feature for embedded documents
module Mongoid #:nodoc:
module Criterion #:nodoc:
module Exclusion
def only(*args)
clone.tap do |crit|
crit.options[:fields] ||= {}
crit.options[:fields][:only] = args.flatten if args.any?
end
end
end
module Optional
# Adds a criterion to the +Criteria+ that specifies the maximum number of
# results to return. This is mostly used in conjunction with <tt>skip()</tt>
# to handle paginated results.
#
# Options:
#
# value: An +Integer+ specifying the max number of results. Defaults to 20.
# hash: A +Hash+ specifying the max number of results for the embedded collections.
#
# Example:
#
# <tt>criteria.limit(100)</tt>
# <tt>criteria.limit(100, { :contents => 5 })</tt>
# <tt>criteria.limit(:contents => 5)</tt>
#
# Returns: <tt>self</tt>
def limit(*args)
clone.tap do |crit|
arguments = args.first || 20
fields = nil # hash of embedded collections
case arguments
when Integer
crit.options[:limit] = arguments
fields = args[1] if args.size > 1
when Hash
fields = arguments
end
if fields
crit.options[:fields] ||= {}
crit.options[:fields][:limit] = fields
end
end
end
end
end
module Contexts #:nodoc:
class Mongo
# Filters the field list. If no fields have been supplied, then it will be
# empty. If fields have been defined then _type will be included as well.
def process_options
fields = options[:fields]
only = fields.delete(:only) if fields
limits = fields.delete(:limit) if fields
# only ?
if only && only.size > 0
only << :_type if !only.include?(:_type)
only.each do |field|
options[:fields].merge!(field => 1)
end
end
# limit for embedded collections ?
if limits && limits.size > 0
limits.each do |field, limit|
options[:fields][field] = { '$slice' => limit }
end
end
options.dup
end
end
end
end