Mastering Object-oriented Python

Representation, persistence, state, and usability

When looking at a configuration file, we're looking at a human-friendly version of the state of one or more objects. When we edit a configuration file, we're changing the persistent state of an object that will get reloaded when the application is started (or restarted.) We have two common ways to look at a configuration file:

• A mapping or a group of mappings from parameter names to values
• A serialized object that's more than a simple mapping

When we try to reduce a configuration file to a mapping, we might be limiting the scope of relationships that may exist within the configuration. In a simple mapping, everything must be referred to by a name, and we have to work through the same key design issues ...