module Dynamoid::Finders::ClassMethods
Public Instance Methods
Find one or many objects, specified by one id or an array of ids.
@param [Array/String] *id an array of ids or one single id
@return [Dynamoid::Document] one object or an array of objects, depending on whether the input was an array or not
@since 0.2.0
# File lib/dynamoid/finders.rb, line 28 def find(*ids) options = if ids.last.is_a? Hash ids.slice!(-1) else {} end expects_array = ids.first.kind_of?(Array) ids = Array(ids.flatten.uniq) if ids.count == 1 result = self.find_by_id(ids.first, options) expects_array ? Array(result) : result else find_all(ids) end end
Return objects found by the given array of ids, either hash keys, or hash/range key combinations using BatchGet. Returns empty array if no results found.
@param [Array<ID>] ids @param [Hash] options: Passed to the underlying query.
@example
find all the user with hash key User.find_all(['1', '2', '3']) find all the tweets using hash key and range key with consistent read Tweet.find_all([['1', 'red'], ['1', 'green']], :consistent_read => true)
# File lib/dynamoid/finders.rb, line 57 def find_all(ids, options = {}) items = Dynamoid.adapter.read(self.table_name, ids, options) items ? items[self.table_name].map{|i| from_database(i)} : [] end
Find all objects by hash and range keys.
@example find all ChamberTypes whose level is greater than 1
class ChamberType include Dynamoid::Document field :chamber_type, :string range :level, :integer table :key => :chamber_type end ChamberType.find_all_by_composite_key('DustVault', range_greater_than: 1)
@param [String] hash_key of the objects to find @param [Hash] options the options for the range key @option options [Range] :range_value find the range key within this range @option options [Number] :range_greater_than find range keys greater than this @option options [Number] :range_less_than find range keys less than this @option options [Number] :range_gte find range keys greater than or equal to this @option options [Number] :range_lte find range keys less than or equal to this
@return [Array] an array of all matching items
# File lib/dynamoid/finders.rb, line 107 def find_all_by_composite_key(hash_key, options = {}) Dynamoid.adapter.query(self.table_name, options.merge({hash_value: hash_key})).collect do |item| from_database(item) end end
Find all objects by using local secondary or global secondary index
@example
class User include Dynamoid::Document field :email, :string field :age, :integer field :gender, :string field :rank :number table :key => :email global_secondary_index :hash_key => :age, :range_key => :gender end User.find_all_by_secondary_index(:age => 5, :range => {"rank.lte" => 10})
@param [Hash] eg: {:age => 5} @param [Hash] eg: {“rank.lte” => 10} @param [Hash] options - @TODO support more options in future such as
query filter, projected keys etc
@return [Array] an array of all matching items
# File lib/dynamoid/finders.rb, line 132 def find_all_by_secondary_index(hash, options = {}) range = options[:range] || {} hash_key_field, hash_key_value = hash.first range_key_field, range_key_value = range.first range_op_mapped = nil if range_key_field range_key_field = range_key_field.to_s range_key_op = "eq" if range_key_field.include?(".") range_key_field, range_key_op = range_key_field.split(".", 2) end range_op_mapped = RANGE_MAP.fetch(range_key_op) end # Find the index index = self.find_index(hash_key_field, range_key_field) raise Dynamoid::Errors::MissingIndex if index.nil? # query opts = { :hash_key => hash_key_field.to_s, :hash_value => hash_key_value, :index_name => index.name, } if range_key_field opts[:range_key] = range_key_field opts[range_op_mapped] = range_key_value end Dynamoid.adapter.query(self.table_name, opts).map do |item| from_database(item) end end
Find one object directly by hash and range keys
@param [String] hash_key of the object to find @param [String/Number] range_key of the object to find
# File lib/dynamoid/finders.rb, line 82 def find_by_composite_key(hash_key, range_key, options = {}) find_by_id(hash_key, options.merge({:range_key => range_key})) end
Find one object directly by id.
@param [String] id the id of the object to find
@return [Dynamoid::Document] the found object, or nil if nothing was found
@since 0.2.0
# File lib/dynamoid/finders.rb, line 69 def find_by_id(id, options = {}) if item = Dynamoid.adapter.read(self.table_name, id, options) from_database(item) else nil end end
Find using exciting method_missing
finders attributes. Uses criteria chains under the hood to accomplish this neatness.
@example find a user by a first name
User.find_by_first_name('Josh')
@example find all users by first and last name
User.find_all_by_first_name_and_last_name('Josh', 'Symonds')
@return [Dynamoid::Document/Array] the found object, or an array of found objects if all was somewhere in the method
@since 0.2.0
# File lib/dynamoid/finders.rb, line 177 def method_missing(method, *args) if method =~ /find/ finder = method.to_s.split('_by_').first attributes = method.to_s.split('_by_').last.split('_and_') chain = Dynamoid::Criteria::Chain.new(self) chain.query = Hash.new.tap {|h| attributes.each_with_index {|attr, index| h[attr.to_sym] = args[index]}} if finder =~ /all/ return chain.all else return chain.first end else super end end