Active Cloud DB: A Database-Agnostic HTTP API to Key-Value Datastores

In this paper, we present a technique that connects web applications to cloud-based distributed datastore technologies that implement the Google App Engine cloud datastore API. We implement our approach as a Google App Engine (GAE) application that we employ to expose the GAE datastore API to developers – for use with any language and framework. We evaluate this application on both GAE and over AppScale, the open-source implementation of GAE that removes the programming and library restrictions of GAE and that enables GAE applications to execute on virtualized cluster resources, including Eucalyptus and EC2, without modification. As part of this work, we extend AppScale with simple caching support to improve the performance of datastore access and evaluate our technique with and without this support. We also make use of this support within multiple prototypes (e.g. Ruby/Rails, Python/Django) to show the ease-of-use and applicability of our contribution to other web development environments.