Class: Mack::Data::Bridge

Inherits:
Object show all
Defined in:
lib/mack-data_factory/orm_api_bridge/bridge.rb

Overview

Different ORMs have different API at getting object from the store. The ORM bridge is an attempt to have a common API that the data_factory can use to get at the objects it needed.

Currently there are 2 orm bridges implemented: DataMapper and ActiveRecord. But developers are free to develop another adapter.

Although this feature is called an “ORM” bridge, the API that it’s trying to bridge doesn’t necessarily have to be of an ORM. As long as the module you’re bridging can respond to these API, you can use it as a valid adapter.

This feature is an advanced feature of the Data Factory, and it’s very useful in a case where you have some legacy data sitting somewhere, or you may have a collection of data that is obtained through a very costly sql query (so doing it many times is obviously not acceptable). So you may want to build a class that can preload all the data, then register itself to the OrmRegistry.

The most important method that a “handler” must implement is the can_handle method. When the DataFactory is handling a certain object, it will attempt to find the appropriate API module that can handle that object, so it will ask all the registered handlers of the OrmRegistry, and the first one to answer yes to the question will be the handler of the object. When a handler say yes to the question, it’s expected that the handler implement all the methods defined in the Bridge class.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Bridge

Returns a new instance of Bridge.



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 41

def initialize
  OrmRegistry.add(Mack::Data::OrmBridge::ActiveRecord.new)
  OrmRegistry.add(Mack::Data::OrmBridge::DataMapper.new)
end

Instance Method Details

#count(obj, *args) ⇒ Object

Get the total number of records for the given obj model

Parameters:

obj: the object model class
args: the list of arguments



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 87

def count(obj, *args)
  handler(obj).count(obj, *args)
end

#get(obj, *args) ⇒ Object

Get a record from the given obj model. In active record implementation: this will get translated to obj.find(*args)

Parameters:

obj: the object model class
args: the list of arguments



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 55

def get(obj, *args)
  handler(obj).get(obj, *args)
end

#get_all(obj, *args) ⇒ Object

Get all records from the given obj model

Parameters:

obj: the object model class
args: the list of arguments



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 66

def get_all(obj, *args)
  handler(obj).get_all(obj, *args)
end

#get_first(obj, *args) ⇒ Object

Get the first record from the given obj model

Parameters:

obj: the object model class
args: the list of arguments



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 77

def get_first(obj, *args)
  handler(obj).get_first(obj, *args)
end

#save(obj, *args) ⇒ Object

Commit changes made to the obj model

Parameters:

obj: the object model class
args: the list of arguments



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# File 'lib/mack-data_factory/orm_api_bridge/bridge.rb', line 98

def save(obj, *args)
  handler(obj).save(obj, *args)
end