1. A method for enforcing context model based Service-Oriented Architecture (SOA) policies, comprising: gathering, via a policy engine device, instance documents related to policy enforcement according to a business requirement, where the instance documents are instantiated from corresponding schema documents; generating an instantiated context model comprising references to the gathered instance documents from a context model definition; generating a policy set to be enforced via the instantiated context model according to the gathered instance documents; determining an enforcement sequence of policies in the policy set; applying the policies to the instantiated context model according to the enforcement sequence; and providing context model-based forward chaining, comprising: determining whether the instantiated context model should be updated; if the instantiated context model should be updated: updating the instantiated context model with at least one updated instance document comprising: executing an updating operation to create the at least one updated instance document; detecting and resolving a conflict caused by the updating operation; generating the updated instantiated context model according to the at least one updated instance document and the instantiated context model; and re-applying the policies to only the at least one updated instance document within the updated instantiated context model according to the enforcement sequence.
1. A method for enforcing context model based Service-Oriented Architecture (SOA) policies, comprising: gathering, via a policy engine device, instance documents related to policy enforcement according to a business requirement, where the instance documents are instantiated from corresponding schema documents; generating an instantiated context model comprising references to the gathered instance documents from a context model definition; generating a policy set to be enforced via the instantiated context model according to the gathered instance documents; determining an enforcement sequence of policies in the policy set; applying the policies to the instantiated context model according to the enforcement sequence; and providing context model-based forward chaining, comprising: determining whether the instantiated context model should be updated; if the instantiated context model should be updated: updating the instantiated context model with at least one updated instance document comprising: executing an updating operation to create the at least one updated instance document; detecting and resolving a conflict caused by the updating operation; generating the updated instantiated context model according to the at least one updated instance document and the instantiated context model; and re-applying the policies to only the at least one updated instance document within the updated instantiated context model according to the enforcement sequence. 15. The method according to claim 1 , where the updating operation to create the at least one updated instance document comprises at least one of adding an instance document to the instantiated context model, modifying an instance document within the instantiated context model, and removing an instance document from the instantiated context model.