Enhancing applications with filtering of XML message streams

Modern applications often have to process and filter information in XML format for reasons of interoperability. Often times those XML messages arrive from publisher at unpredictable rates and must be processed in near real-time to answer complex filtering queries. Towards this end, we introduce Seshat -- the content-based Domain Specific XML stream processing engine for meeting the needs of different subscribing applications. Seshat provides the full support for Boolean logic operators including negation and also supports supplemental operators, such as substring search. Its simple query framework enables filtering queries with variable substitution predicates. We describe the query processing engine and also the implementation details. Seshat engine can be potentially deployed in publish-subscribe brokers for selective message filtering and replication as well as in subscribing applications that need to process the arriving XML messages independently for the purpose of validation. We provide preliminary performance results of the filtering engine and its simple Domain Specific Language processing queries on several real-world XML datasets.