SOA Patterns > Legacy Encapsulation Patterns > Legacy Wrapper
Legacy Wrapper (Erl, Roy)
How can wrapper services with non-standard contracts be prevented from spreading indirect consumer-to-implementation coupling?
Problem
Wrapper services required to encapsulate legacy logic are often forced to introduce a non-standard service contract with high technology coupling requirements, resulting in a proliferation of implementation coupling throughout all service consumer programs.
Solution
The non-standard wrapper service can be replaced by or further wrapped with a standardized service contract that extracts, encapsulates, and possibly eliminates legacy technical details from the contract.
Application
A custom service contract and required service logic need to be developed to represent the proprietary legacy interface.
Impacts
The introduction of an additional service adds a layer of processing and associated performance overhead.
Architecture
Service
Tight coupling of the service logic to both the legacy API and the service contract alleviates service consumers from implementation coupling.
Related Patterns in This Catalog
Data Format Transformation, Data Model Transformation, Entity Abstraction, File Gateway, Multi-Channel Endpoint, Protocol Bridging, Rules Centralization, Service Data Replication, Utility Abstraction
Related Patterns in Other Catalogs
Related Service-Oriented Computing Goals
This pattern is covered in SOACP Module 7: Advanced SOA Design & Architecture with Services & Microservices.
For more information regarding the SOA Certified Pofessional (SOACP) curriculum,
visit www.arcitura.com/soa.
This page contains excerpts from:
SOA Design Patterns by Thomas Erl
(ISBN: 0136135161, Hardcover, Full-Color, 400+ Illustrations, 865 pages)
For more information about this book, visit www.arcitura.com/books.