Hello all: Being new to Drools, I'm currently uncertain if it's "a good idea" to use Drools for the following "multi-domain" scenario. -- I guess Drools is appropriate, but I currently can't imagine (a) which Drools parts to configure after which strategies (static/cachable vs. dynamic), and thus also (b) how to organize the rule structures and their goals (what input/output, what is cachable). The scenario is as follows: A /Businesses Service/ *Java Web App* shall manage /N/ distinct shops for /N/ distinct shop owners, thus having /N/ "domains" with their own fact model (extended from basic model that is the same for all shops), their own rules, etc. The shared but extensible 'Product' model is for rather *static* product and product set definitions, and it basically consists of: (a) some basic attributes (product name, description, etc.) AND (b) several custom (=dynamic) attributes, independly definable by each shop owner (attrib name, type, value(s)). Non-technical shop owners define their products, "product sets", customer types, and last but not least use the "price model" to assign prices to products and product sets, depending on some fixed (e.g. customer_type ::= {NEW_CUSTOMER, REGULAR_CUSTOMER, VIP,...}, taxes, etc.) and probably some custom price aspects like: - quantity ranges, - charges for a specific dyn. product attribute (e.g. t-shirts of 'size==XXL' => +10% of basic price), - additional promotional price discounts (or charges) for specific products or sets. Product defs and taxes are rather /static/ once created, whereas prices and discounts are /highly dynamic/, i.e. should be externally changeable at need by the non-technical shop owners (IMHO /decision tables/ are the most appropriate way here). Customers are presented a shop's Online Catalog (or Ordering Form) showing the prices intended for them, of course, but probably also the other customer-type specific prices -- for them to see their current savings or the possible savings after a customer-type "upgrade". Finally, customers place orders via the web interface and the system processes these orders (via further rules). ... My unclarities are: For the rather static "product (set) definitions" (both type def & instance data), Should I better use a traditional way via *configuration files* OR could I use Drools with some kind of "product definition rules" (generated from /decision tables/)??? What is a good strategy for realizing the "product def rules" in Drools? I.e., What is static and what dynamic? What is generated once vs. in real-time, and what is cached vs. physically stored in the database? For the highly dynamic "price assignments" (after some pre-defined as well as custom pricing aspects): How could a pricing table with custom pricing parameters look like? OR equivalently: How to define a pricing rule that dependens on a custom product attribute? The intention is similar to: WHEN ( aProduct.extendedAttributes.size == 'XXL' ) THEN ( aProduct.price = aProduct.standardPrice * 1.10 ) //+10% of std. price When would the defined pricing rules run and what would they generate? -- I.e., will all rules re-run each time a rule file changes with the goal of generating cacheable "price lists", or will they even run on any catalog request (thus generating the price lists on-the-fly)??? In such a not so uncommon JavaEE Web App shopping scenario: Generally, which kind of rules are feasible besides the "product (set) definition" and "price controling" rules? I guess rules such as the following could be practicable: fact model type definition rules (that construct and load new model types). GUI generation rules for Swing/SWT and Web GUIs (after some type-to-component mappings configured via rules or decision tables). authentication & authorization rules. Knowing the required artefacts and their generation strategies (cached vs. life) from the answers of the above questions: How do I have to configure Drools (& Guvnor) for *N parallel running* online shops? I.e., Do I instantiate 1 rule engine per shop, or do I share 1 for all shops? Do I load the generic fact model (that supports custom enhancements) once per shop, or share it among them? Which parts can be cached in "Application Scope"? (supposable N KnowledgeBases with pre-generated stuff, 1 for each shop) In which kind of JEE Session Beans do I have to integrate which kind of Drools Knowlege Session beans? The clarification of these issues would currently help me a lot. Thank you very much for any help and development hints in advance. Best regards Peter -- View this message in context: http://drools.46999.n3.nabble.com/Newbie-Drools-and-this-multi-user-domai... Sent from the Drools: User forum mailing list archive at Nabble.com.