Working Definitions

T
he request object is an object which is filled in by the dispatcher module, and should only be read from.

Output objects are just wrappers around HTML constructs, and their only job is to hold other Output objects and spew out their HTML representation. Think of them as the object which renders the output --- the object which has the render method. See Infrastructure Perspective: Output Objects for more information.

The CSPage object is just a container for output objects which is initialized to contain the characteristic department header and footer. The render_output method of this object returns the HTML code which represents the page.

Query objects are just wrappers around SQL queries. They take as input all the information needed for a query, construct a query in the appropriate format, send it over to MySQL, properly package the results, and send it back to you. They know how to talk to MySQL, which database to talk to, the username and password, etc. See the SQL query interface for more information.

Controls are abstractions of logical unit of data. They take in logical information (name of the field from which the data should be obtained) and convert them into output objects. The controls use the logical data which they have to contruct a query object. The value returned by the query object is then used to contruct an output object. So in short controls convert logical pieces of information into one or more output objects (returned by the output_* methods). Think of Controls as the classes with output_* methods. See Infrastructure Perspective: Controls for more information on controls.

A Display Class is the main class defined in any .py in the docs directory. A display class takes a request object as input (in its constructor) and modifies the CSPage object it gets as an argument to make_page by inserting lots of output objects into it. If it is a database display, the Display class defines controls which generate output objects. So the output objects inserted are just the output objects generated by the controls which go into defining the Display class. See Infrastructure Perspective: Display Classes and Infrastructure Perspective: Database Displays for more information on display classes.