Can you share more details? What will be the main subject of your DSS (business, finance, agriculture, education, etc.)? Are you developing one or multiple DSS? If multiples, are they on different subjects? Are you looking for a theoretical framework or for a tools?
Sorry, if I disappoint you, but development of DSS is a longer process requiring understanding of the needs, roles and responsibilities of decision makers, information available, decision making criteria and many, many other important aspects. Therefore there is no such thing like DSS "Generator". You have to gather answers to above mentioned points and then, considering your available technical and financial resources you may think about the DSS design.
The ubiquitous MS Excell, the Microsoft spreadsheet software, is perhaps the mist widely used DSS generator on the planet. People build very many DSSs for finance, accounting, marketing/sales, inventory management, and other business applications using excel. It is the first tool that most reach out to.
My above response was prompted by the title of your posting. From the body of your posting I see you have asked for a framework for a DSS Generator. A DSS generator is nothing but a hardware-software platform that allows one to build a specific DSS. In this contex, a framework might be just the platform architecture ... I.e., the computing system architecture. On the other hand, there also exist frameworks for a DSS. The most well-known are thoset due to Sprague and Carlson (1980) and Bonczek, Holsapple, and Winston (1981). The latter is more general and subsumes the former (which takes a narrower point of view). I hooe this is what you were interested in.
I believe a key requirement for building a Decision Support system Generator is to provide a series of quantitative and qualitative mechanisms for integrating competing information from distributed agents. The following article sheds some light to that aspect of DSS research. Take a look..
Article Building Blocks for a Decision Based Integrated Product Deve...