  The diversity of data management systems affords developers the luxury of
building systems with heterogeneous systems that address needs that are unique
to the data. It allows one to mix-n-match systems that can store, query,
update, and process data, based on specific use cases. However, this
heterogeneity brings with it the burden of developing custom interfaces for
each data management system. Developers are required to build high-performance
APIs for data access while adopting best-practices governing security, data
privacy, and access control. These include user authentication, data
authorization, role-based access control, and audit mechanisms to avoid
compromising the security standards mandated by data providers.
  In this paper, we present Bindaas, a secure, extensible big data middleware
that offers uniform access to diverse data sources. By providing a standard
RESTful web service interface to the data sources, Bindaas exposes query,
update, store, and delete functionality of the data sources as data service
APIs, while providing turn-key support for standard operations involving
security, access control, and audit-trails. Bindaas consists of optional
features, such as query and response modifiers as well as plugins that
implement composable and reusable data operations on the data. The research
community has deployed Bindaas in various production environments in
healthcare. Our evaluations highlight the efficiency of Bindaas in serving
concurrent requests to data source instances. We further observe that the
overheads caused by Bindaas on the data sources are negligible.
