Module abstract_adapter

source code

Adapter Overview

Adapters provide the bridge between the mapped object and the data store. There are several layers to an adapter request and response:

    Req  Resp
 pyperry.base.Base
     |     ^
     V     |
   Processors
     |     ^
     V     |
   Model Bridge
     |     ^
     V     |
   Middlewares
     |     ^
     V     |
     Adapter
       \/
     Database

The request is initiated by the pyperry.base.Base class and passes through the adapter stack returning a response. Within the stack the request goes through a series of configurable stack items: processors, and middlewares before being passed to the appropriate adapter method. That adapter method then executes the requested action and returns the results back through the stack until returning to Base.

Processors and middlewares are ways of customizing requests and responses. There is a middleware that is always installed called the ModelBridge. It takes the raw response of the adapter and converts it to mapped objects. The only difference between a middleware and a processor is that the objects returned to a processor are always instantiated records whereas middlewares receive the raw response.