Abstract: Approaches for extracting data from data sources using a generic web service adaptor that implements a web services processing framework. Metadata stored in the database is read to identify specified named entities from a plurality of web service providers. Application protocol interface (API) semantics and configurations are retrieved from the metadata. Metadata objects for the specified named entities are fetched. Web services operation API signatures of the metadata objects are validated by comparing with predefined web services operation API signatures stored in the metadata. Web services operations for the specified named entities of the web service providers comprising the data sources are performed to obtain returned result objects. The returned result objects are serialized to XML using the same framework as used by the source web service. An adaptor may be configured to support the plurality of web service providers based on configurations.