module Mongo::Conversions
Utility module to include when needing to convert certain types of objects to mongo-friendly parameters.
Constants
- ASCENDING_CONVERSION
- DESCENDING_CONVERSION
Public Instance Methods
Converts the supplied Array
to a Hash
to pass to
mongo as sorting parameters. The returned Hash
will vary
depending on whether the passed Array
is one or two
dimensional.
Example:
array_as_sort_parameters([["field1", :asc],
["field2", :desc]])
=> { "field1" =>
1, "field2" => -1}
# File lib/mongo/utils/conversions.rb, line 55 def array_as_sort_parameters(value) order_by = BSON::OrderedHash.new if value.first.is_a? Array value.each do |param| if (param.class.name == "String") order_by[param] = 1 else order_by[param[0]] = sort_value(param[1]) unless param[1].nil? end end elsif !value.empty? if order_by.size == 1 order_by[value.first] = 1 else order_by[value.first] = sort_value(value[1]) end end order_by end
Allows sort parameters to be defined as a Hash. Does not allow usage of un-ordered hashes, therefore Ruby 1.8.x users must use BSON::OrderedHash.
Example:
hash_as_sort_parameters({:field1 => :asc, "field2" =>
:desc})
=> { "field1" => 1, "field2"
=> -1}
# File lib/mongo/utils/conversions.rb, line 32 def hash_as_sort_parameters(value) if RUBY_VERSION < '1.9' && !value.is_a?(BSON::OrderedHash) raise InvalidSortValueError.new( "Hashes used to supply sort order must maintain ordering." + "Use BSON::OrderedHash." ) else order_by = value.inject({}) do |memo, (key, direction)| memo[key.to_s] = sort_value(direction) memo end end order_by end
Converts the String
, Symbol
, or
Integer
to the corresponding sort value in MongoDB.
Valid conversions (case-insensitive):
ascending, asc, :ascending, :asc, 1
=> 1
descending, desc, :descending, :desc, -1
=> -1
If the value is invalid then an error will be raised.
# File lib/mongo/utils/conversions.rb, line 99 def sort_value(value) return value if value.is_a?(Hash) val = value.to_s.downcase return 1 if ASCENDING_CONVERSION.include?(val) return -1 if DESCENDING_CONVERSION.include?(val) raise InvalidSortValueError.new( "#{self} was supplied as a sort direction when acceptable values are: " + "Mongo::ASCENDING, 'ascending', 'asc', :ascending, :asc, 1, Mongo::DESCENDING, " + "'descending', 'desc', :descending, :desc, -1.") end
Converts the supplied String
or Symbol
to a
Hash
to pass to mongo as a sorting parameter with ascending
order. If the String
is empty then an empty Hash
will be returned.
Example:
*DEPRECATED
string_as_sort_parameters("field")
=> {
"field" => 1 }
string_as_sort_parameters("")
=> {}
# File lib/mongo/utils/conversions.rb, line 85 def string_as_sort_parameters(value) return {} if (str = value.to_s).empty? { str => 1 } end