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Modern web applications are distributed across a browser-based client and a cloud-based server. Distribution provides access to remote resources, accessed over the web and shared by clients. Much of the complexity of inspecting and evolving web applications lies in their distributed nature. Also, the majority of mature program analysis and transformation tools works only with centralized software. Inspired by business process re-engineering, in which remote operations can be insourced back in house to restructure and outsource anew, we bring an analogous approach to the re-engineering of web applications. Our target domain are full-stack JavaScript applications that implement both the client and server code in this language. Our approach is enabled by Client Insourcing, a novel automatic refactoring that creates a semantically equivalent centralized version of a distributed application. This centralized version is then inspected, modified, and redistributed to meet new requirements. After describing the design and implementation of Client Insourcing, we demonstrate its utility and value in addressing changes in security, reliability, and performance requirements. By reducing the complexity of the non-trivial program inspection and evolution tasks performed to meet these requirements, our approach can become a helpful aid in the re-engineering of web applications in this domain.
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D-Goldilocks: Automatic Redistribution of Remote Functionalities for Performance and Efficiency
Distributed applications enhance their execution by using remote resources. However, distributed execution incurs communication, synchronization, fault-handling, and security overheads. If these overheads are not offset by the yet larger execution enhancement, distribution becomes counterproductive. For maximum benefits, the distribution’s granularity cannot be too fine or too crude; it must be just right. In this paper, we present a novel approach to re-architecting distributed applications, whose distribution granularity has turned ill-conceived. To adjust the distribution of such applications, our approach automatically reshapes their remote invocations to reduce aggregate latency and resource consumption. To that end, our approach insources a remote functionality for local execution, splits it into separate functions to profile their performance, and determines the optimal redistribution based on a cost function. Redistribution strategies combine separate functions into single remotely invocable units. To automate all the required program transformations, our approach introduces a series of domainspecific automatic refactorings. We have concretely realized our approach as an analysis and automatic program transformation infrastructure for the important domain of full-stack JavaScript applications, and evaluated its value, utility, and performance on a series of real-world cross-platform mobile apps. Our evaluation results indicate that our approach can become a useful tool for software developers charged with the challenges of re-architecting distributed applications.
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- Award ID(s):
- 1717065
- PAR ID:
- 10154791
- Date Published:
- Journal Name:
- 2020 IEEE 27th International Conference on Software Analysis, Evolution and Reengineering (SANER)
- Page Range / eLocation ID:
- 251 to 260
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SANER48275.2020.9054870
