Move all persistence bindings to adapters

.rubocop_todo.yml

@@ -33,7 +33,7 @@ Metrics/MethodLength:
 # Offense count: 2
 # Configuration parameters: CountComments.
 Metrics/ModuleLength:
-  Max: 110
+  Max: 114
 
 # Offense count: 3
 Metrics/PerceivedComplexity:

README.md

@@ -150,6 +150,30 @@ ActiveData has modular architecture, so it is required to include modules to obt
 #### ReferencesMany
 #### Interacting with ActiveRecord
 
+### Persistence Adapters
+
+Adapter definition syntax:
+```ruby
+ActiveData.persistence_adapter('ClassName') do |data_source, primary_key, scope_proc|
+  CustomAdapter.new(data_source, primary_key, scope_proc) # or anything that have similar interface to ActiveData::Model::Associations::PersistenceAdapters::Base
+end
+```
+Where  
+`ClassName` - name of model class or one of ancestors  
+`data_source` - name of data source class  
+`primary_key` - key to search data  
+`scope_proc` - additional proc for filtering  
+
+All required interface for adapters described in `ActiveData::Model::Associations::PersistenceAdapters::Base`.
+
+Adapter for ActiveRecord is `ActiveData::Model::Associations::PersistenceAdapters::ActiveRecord`.
+```ruby
+ActiveData.persistence_adapter('ActiveRecord::Base') do |data_source, primary_key, scope_proc|
+  PersistenceAdapters::ActiveRecord.new(data_source, primary_key, scope_proc)
+end
+```
+So, all AR models will use `PersistenceAdapters::ActiveRecord` by default.
+
 ### Primary
 
 ### Persistence

lib/active_data.rb

@@ -12,6 +12,8 @@
 require 'active_data/extensions'
 require 'active_data/config'
 require 'active_data/railtie' if defined? Rails
+require 'active_data/model'
+require 'active_data/persistence_adapters'
 
 module ActiveData
   BOOLEAN_MAPPING = {
@@ -127,9 +129,11 @@ def self.config
       ActiveData::UUID.parse_int value
     end
   end
-end
 
-require 'active_data/model'
+  persistence_adapter('ActiveRecord::Base') do |data_source, primary_key, scope_proc|
+    ActiveData::Model::Associations::PersistenceAdapters::ActiveRecord.new(data_source, primary_key, scope_proc)
+  end
+end
 
 ActiveSupport.on_load :active_record do
   require 'active_data/active_record/associations'

lib/active_data/config.rb

@@ -3,7 +3,7 @@ class Config
     include Singleton
 
     attr_accessor :include_root_in_json, :i18n_scope, :logger, :primary_attribute,
-      :_normalizers, :_typecasters
+      :_normalizers, :_typecasters, :_persistence_adapters
 
     def self.delegated
       public_instance_methods - superclass.public_instance_methods - Singleton.public_instance_methods
@@ -16,6 +16,7 @@ def initialize
       @primary_attribute = :id
       @_normalizers = {}
       @_typecasters = {}
+      @_persistence_adapters = {}
     end
 
     def normalizer(name, &block)
@@ -26,6 +27,18 @@ def normalizer(name, &block)
       end
     end
 
+    def persistence_adapter(klass, &block)
+      klass_name = klass.to_s.camelize
+      if block
+        _persistence_adapters[klass_name] = block
+      else
+        klass_const = klass_name.constantize
+        adapter = _persistence_adapters.values_at(*klass_const.ancestors.map(&:to_s)).compact.first
+        raise PersistenceAdapterMissing, klass unless adapter
+        adapter
+      end
+    end
+
     def typecaster(*classes, &block)
       classes = classes.flatten
       if block

lib/active_data/errors.rb

@@ -91,4 +91,17 @@ def initialize(*classes)
       EOS
     end
   end
+
+  class PersistenceAdapterMissing < NoMethodError
+    def initialize(data_source)
+      super <<-EOS
+Could not find persistence adapter for #{data_source}
+You can define it with:
+
+  ActiveData.persistence_adapter('#{data_source}') do |data_source, primary_key, scope_proc|
+    # do some staff with value and options
+  end
+      EOS
+    end
+  end
 end

lib/active_data/model/associations.rb

@@ -1,8 +1,8 @@
 require 'active_data/model/associations/collection/proxy'
 require 'active_data/model/associations/collection/embedded'
-require 'active_data/model/associations/collection/referenced'
 
 require 'active_data/model/associations/reflections/base'
+require 'active_data/model/associations/reflections/embed_reflection'
 require 'active_data/model/associations/reflections/embeds_one'
 require 'active_data/model/associations/reflections/embeds_many'
 require 'active_data/model/associations/reflections/reference_reflection'
@@ -13,6 +13,7 @@
 require 'active_data/model/associations/embed_association'
 require 'active_data/model/associations/embeds_one'
 require 'active_data/model/associations/embeds_many'
+require 'active_data/model/associations/reference_association'
 require 'active_data/model/associations/references_one'
 require 'active_data/model/associations/references_many'
 

lib/active_data/model/associations/embeds_one.rb

@@ -48,7 +48,9 @@ def load_target
         def default
           return if evar_loaded?
 
-          default = reflection.default(owner) or return
+          default = reflection.default(owner)
+
+          return unless default
 
           object = if default.is_a?(reflection.klass)
             default

lib/active_data/model/associations/persistence_adapters/active_record.rb

@@ -0,0 +1,62 @@
+require 'active_data/model/associations/persistence_adapters/active_record/referenced_proxy'
+
+module ActiveData
+  module Model
+    module Associations
+      module PersistenceAdapters
+        class ActiveRecord < Base
+          TYPES = {
+            integer: Integer,
+            float: Float,
+            decimal: BigDecimal,
+            datetime: Time,
+            timestamp: Time,
+            time: Time,
+            date: Date,
+            text: String,
+            string: String,
+            binary: String,
+            boolean: Boolean
+          }.freeze
+
+          alias_method :data_type, :data_source
+
+          def build(attributes)
+            data_source.new(attributes)
+          end
+
+          def scope(owner, source)
+            scope = data_source.unscoped
+
+            if scope_proc
+              scope = if scope_proc.arity.zero?
+                scope.instance_exec(&scope_proc)
+              else
+                scope.instance_exec(owner, &scope_proc)
+              end
+            end
+
+            scope.where(primary_key => source)
+          end
+
+          def identify(object)
+            object[primary_key]
+          end
+
+          def primary_key
+            @primary_key ||= :id
+          end
+
+          def primary_key_type
+            column = data_source.columns_hash[primary_key.to_s]
+            TYPES[column.type]
+          end
+
+          def referenced_proxy(association)
+            ReferencedProxy.new(association)
+          end
+        end
+      end
+    end
+  end
+end

lib/active_data/model/associations/persistence_adapters/active_record/referenced_proxy.rb

@@ -0,0 +1,31 @@
+module ActiveData
+  module Model
+    module Associations
+      module PersistenceAdapters
+        class ActiveRecord < Base
+          class ReferencedProxy < ActiveData::Model::Associations::Collection::Proxy
+            # You can't create data directly through ActiveRecord::Relation
+            METHODS_EXCLUDED_FROM_DELEGATION = %w(build create create!).map(&:to_sym).freeze
+
+            attr_reader :association
+            delegate :scope, to: :@association
+
+            def method_missing(method, *args, &block)
+              delegate_to_scope?(method) ? scope.send(method, *args, &block) : super
+            end
+
+            def respond_to_missing?(method, include_private = false)
+              delegate_to_scope?(method) || super
+            end
+
+          private
+
+            def delegate_to_scope?(method)
+              METHODS_EXCLUDED_FROM_DELEGATION.exclude?(method) && scope.respond_to?(method)
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/active_data/model/associations/persistence_adapters/base.rb

@@ -0,0 +1,49 @@
+module ActiveData
+  module Model
+    module Associations
+      module PersistenceAdapters
+        class Base
+          attr_reader :data_source, :primary_key, :scope_proc
+
+          def initialize(data_source, primary_key, scope_proc = nil)
+            @data_source = data_source
+            @primary_key = primary_key
+            @scope_proc = scope_proc
+          end
+
+          def build(_attributes)
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Build new instance of data object by attributes'
+          end
+
+          def scope(_owner, _source)
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Better to be Enumerable'
+          end
+
+          def find_one(owner, identificator)
+            scope(owner, identificator).first
+          end
+
+          def find_all(owner, identificators)
+            scope(owner, identificators).to_a
+          end
+
+          def identify(_object)
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Field to be used as primary_key for object'
+          end
+
+          def data_type
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Type of data object for type_check'
+          end
+
+          def primary_key_type
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Ruby data type'
+          end
+
+          def referenced_proxy
+            raise NotImplementedError, 'Should be implemented in inhereted adapter. Object to manage proxying of methods to scope.'
+          end
+        end
+      end
+    end
+  end
+end

lib/active_data/model/associations/reference_association.rb

@@ -0,0 +1,11 @@
+module ActiveData
+  module Model
+    module Associations
+      class ReferenceAssociation < Base
+        def scope(source = read_source)
+          reflection.persistence_adapter.scope(owner, source)
+        end
+      end
+    end
+  end
+end