require 'active_support/core_ext/array/wrap'
require 'active_support/core_ext/object/blank'
module ActiveRecord
module QueryMethods
extend ActiveSupport::Concern
included do
(ActiveRecord::Relation::ASSOCIATION_METHODS + ActiveRecord::Relation::MULTI_VALUE_METHODS).each do |query_method|
attr_accessor :"#{query_method}_values"
next if [:where, :having, :select].include?(query_method)
class_eval <<-CEVAL, __FILE__, __LINE__ + 1
def #{query_method}(*args, &block)
new_relation = clone
new_relation.send(:apply_modules, Module.new(&block)) if block_given?
value = Array.wrap(args.flatten).reject {|x| x.blank? }
new_relation.#{query_method}_values += value if value.present?
new_relation
end
CEVAL
end
def select(*args)
if block_given?
to_a.select { |*block_args| yield(*block_args) }
else
new_relation = clone
value = Array.wrap(args.flatten).reject {|x| x.blank? }
new_relation.select_values += value if value.present?
new_relation
end
end
[:where, :having].each do |query_method|
class_eval <<-CEVAL, __FILE__, __LINE__ + 1
def #{query_method}(*args, &block)
new_relation = clone
new_relation.send(:apply_modules, Module.new(&block)) if block_given?
value = build_where(*args)
new_relation.#{query_method}_values += Array.wrap(value) if value.present?
new_relation
end
CEVAL
end
ActiveRecord::Relation::SINGLE_VALUE_METHODS.each do |query_method|
attr_accessor :"#{query_method}_value"
class_eval <<-CEVAL, __FILE__, __LINE__ + 1
def #{query_method}(value = true, &block)
new_relation = clone
new_relation.send(:apply_modules, Module.new(&block)) if block_given?
new_relation.#{query_method}_value = value
new_relation
end
CEVAL
end
end
def extending(*modules)
new_relation = clone
new_relation.send :apply_modules, *modules
new_relation
end
def lock(locks = true, &block)
relation = clone
relation.send(:apply_modules, Module.new(&block)) if block_given?
case locks
when String, TrueClass, NilClass
clone.tap {|new_relation| new_relation.lock_value = locks || true }
else
clone.tap {|new_relation| new_relation.lock_value = false }
end
end
def reverse_order
order_clause = arel.send(:order_clauses).join(', ')
relation = except(:order)
if order_clause.present?
relation.order(reverse_sql_order(order_clause))
else
relation.order("#{@klass.table_name}.#{@klass.primary_key} DESC")
end
end
def arel
@arel ||= build_arel
end
def custom_join_sql(*joins)
arel = table
joins.each do |join|
next if join.blank?
@implicit_readonly = true
case join
when Hash, Array, Symbol
if array_of_strings?(join)
join_string = join.join(' ')
arel = arel.join(join_string)
end
else
arel = arel.join(join)
end
end
arel.joins(arel)
end
def build_arel
arel = table
arel = build_joins(arel, @joins_values) if @joins_values.present?
@where_values.uniq.each do |where|
next if where.blank?
case where
when Arel::SqlLiteral
arel = arel.where(where)
else
sql = where.is_a?(String) ? where : where.to_sql
arel = arel.where(Arel::SqlLiteral.new("(#{sql})"))
end
end
arel = arel.having(*@having_values.uniq.select{|h| h.present?}) if @having_values.present?
arel = arel.take(@limit_value) if @limit_value.present?
arel = arel.skip(@offset_value) if @offset_value.present?
arel = arel.group(*@group_values.uniq.select{|g| g.present?}) if @group_values.present?
arel = arel.order(*@order_values.uniq.select{|o| o.present?}) if @order_values.present?
selects = @select_values.uniq
if selects.present?
selects.each do |s|
@implicit_readonly = false
arel = arel.project(s) if s.present?
end
else
arel = arel.project(@klass.quoted_table_name + '.*')
end
arel = arel.from(@from_value) if @from_value.present?
case @lock_value
when TrueClass
arel = arel.lock
when String
arel = arel.lock(@lock_value)
end if @lock_value.present?
arel
end
def build_where(*args)
return if args.blank?
opts = args.first
case opts
when String, Array
@klass.send(:sanitize_sql, args.size > 1 ? args : opts)
when Hash
attributes = @klass.send(:expand_hash_conditions_for_aggregates, opts)
PredicateBuilder.new(table.engine).build_from_hash(attributes, table)
else
opts
end
end
private
def build_joins(relation, joins)
joined_associations = []
association_joins = []
joins = @joins_values.map {|j| j.respond_to?(:strip) ? j.strip : j}.uniq
joins.each do |join|
association_joins << join if [Hash, Array, Symbol].include?(join.class) && !array_of_strings?(join)
end
stashed_association_joins = joins.select {|j| j.is_a?(ActiveRecord::Associations::ClassMethods::JoinDependency::JoinAssociation)}
non_association_joins = (joins - association_joins - stashed_association_joins).reject {|j| j.blank?}
custom_joins = custom_join_sql(*non_association_joins)
join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, association_joins, custom_joins)
join_dependency.graft(*stashed_association_joins)
@implicit_readonly = true unless association_joins.empty? && stashed_association_joins.empty?
to_join = []
join_dependency.join_associations.each do |association|
if (association_relation = association.relation).is_a?(Array)
to_join << [association_relation.first, association.join_class, association.association_join.first]
to_join << [association_relation.last, association.join_class, association.association_join.last]
else
to_join << [association_relation, association.join_class, association.association_join]
end
end
to_join.each do |tj|
unless joined_associations.detect {|ja| ja[0] == tj[0] && ja[1] == tj[1] && ja[2] == tj[2] }
joined_associations << tj
relation = relation.join(tj[0], tj[1]).on(*tj[2])
end
end
relation.join(custom_joins)
end
def apply_modules(modules)
values = Array.wrap(modules)
@extensions += values if values.present?
values.each {|extension| extend(extension) }
end
def reverse_sql_order(order_query)
order_query.to_s.split(/,/).each { |s|
if s.match(/\s(asc|ASC)$/)
s.gsub!(/\s(asc|ASC)$/, ' DESC')
elsif s.match(/\s(desc|DESC)$/)
s.gsub!(/\s(desc|DESC)$/, ' ASC')
else
s.concat(' DESC')
end
}.join(',')
end
def array_of_strings?(o)
o.is_a?(Array) && o.all?{|obj| obj.is_a?(String)}
end
end
end