A computer-based method and system for processing data obtained from documents retrieved from a computer network during a gathering project is disclosed. Plugging in modular active and consumer plug-ins into the gathering project configures the information processing capability of the gathering process that retrieves the documents. The gathering process retrieves a copy of an electronic document from a server connected to the computer network and returns a document data stream that includes the retrieved document's data and its “properties.” One or more active plug-ins plugged-in to the gathering process is used to add, delete or modify the properties in the document data stream based on the document's contents or properties. The modified document data stream is then passed to one or more consumer plug-ins that use the properties in the modified document data stream to process the document in some manner. An active plug-in can prevent any part of the document data stream from being forwarded to subsequent active or consumer plug-ins in the project. An active plug-in can also control the consumer plug-ins by instructing them to abort processing of a particular document after analyzing some of the document's contents while the document is being processed.