SOA with REST : principles, patterns & constraints for building enterprise solutions with REST

625 Pages·2013·26.89 MB·English

by  Erl, Thomas

Agnostic Capability [428] How can multi- Compensating Service Transaction [443]
purpose service logic be made effectively How can composition runtime exceptions be
consumable and composable? consistently accommodated without requiring
services to lock resources?
Agnostic Context [429] How can multi-purpose
service logic be positioned as an effective Composition Autonomy [444] How can
enterprise resource? compositions be implemented to minimize loss of
autonomy?
Agnostic Sub-Controller [430] How can
agnostic, cross-entity composition logic be Concurrent Contracts [445] How can a service
separated, reused, and governed independently? facilitate multi-consumer coupling requirements
and abstraction concerns at the same time?
Asynchronous Queuing [431] How can a
service and its consumers accommodate isolated Content Negotiation[446] How can a service
failures and avoid unnecessarily locking resources? capability accommodate service consumers
with different data format or representation
Atomic Service Transaction [432] How can a requirements?
transaction with rollback capability be propagated
across messaging-based services? Contract Centralization [447] How can direct
consumer-to-implementation coupling be
Brokered Authentication [433] How can a avoided?
service efficiently verify consumer credentials if
the consumer and service do not trust each other Contract Denormalization [448] How can a
or if the consumer requires access to multiple service contract facilitate consumer programs with
services? differing data exchange requirements?
Canonical Expression [434] How can service Cross-Domain Utility Layer [449] How can
contracts be consistently understood and redundant utility logic be avoided across domain
interpreted? service inventories?
Canonical Protocol [435] How can services be Data Confidentiality [450] How can data within
designed to avoid protcol bridging? a message be protected so that it is not disclosed to
unintended recipients while in transit?
Canonical Resources [436] How can
unnecessary infrastructure resource disparity be Data Format Transformation [451] How can
avoided? services interact with programs that communicate
with different data formats?
Canonical Schema [437] How can services be
designed to avoid data model transformation? Data Model Transformation [452] How can
services interoperate when using different data
Canonical Schema Bus [438] models for the same type of data?
Canonical Versioning [439] How can service Data Origin Authentication [453] How can a
contracts within the same service inventory be service verify that a message originates from a
versioned with minimal impact? known sender and that the message has not been
tampered with in transit?
Capability Composition [440] How can a
service capability solve a problem that requires Decomposed Capability [454] How can a
logic outside of the service boundary? service be designed to minimize the chances of
capability logic deconstruction?
Capability Recomposition [441] How can the
same capability be used to help solve multiple Decoupled Contract [455] How can a service
problems? express its capabilities independently of its
implementation?
Compatible Change [442] How can a service
contract be modified without impacting Direct Authentication [456] How can a service
consumers? verify the credentials provided by a consumer?
(pattern list continued on inside back cover)
Praise for this Book
“This book illuminates the connection of the two domains—SOA and REST—in a man-
ner that is concrete and practical, providing concise application to everyday architec-
tural challenges. Fantastic!”
—Ryan Frazier, Technology Strategist, Microsoft
“SOA can be done in many different ways, and REST has become the most visible new-
comer in the space of potential implementation frameworks. This book illustrates what
architects and developers need to know about RESTful SOA and most importantly
drives home the main point that REST makes as a style for SOA: It is all about designing
service ecosystems and providing clients an easy way to use resources in those ecosys-
tems and even connect them across individual services. This book undoubtedly will
help SOA to reap the benefits from the main value propositions of Web architecture:
decentralization, loose coupling, connectedness, self-describing services, and service
interfaces that are independent from service implementations.”
—Dr. Erik Wilde, Architect, EMC Corporation
“SOA with REST is a tour de force that elegantly applies REST principles to the
industry-standard SOA framework described in prior titles in this series. The book pro-
vides useful guidance to practitioners while staying true in form and spirit to the REST
constraints defined in Roy Fielding’s thesis. The chapters on RESTful contract design
in and of themselves justify the cost of purchase. This book is a must-read for anyone
developing REST services.”
—Dave Slotnick, Enterprise Architect, Rackspace Hosting
“An excellent repertoire of service-oriented patterns that will prove handy when solv-
ing problems in the real world. The REST perspectives and principles will provide com-
plete coverage of modern-day Web 2.0 style approaches. Highly recommended.”
—Sid Sanyal, IT Architect, Zurich Financial Services
“REST is so much more than just another type of interface implementation—SOA with
REST shows how the ecosystem of service compositions changes as new opportuni-
ties arise for service composition architecture designs. A comprehensive guide and a
must-read for any serious IT architect considering REST-style services for application
architectures.”
—Roger Stoffers, Solution Architect, Hewlett Packard
“Service-orientation and REST both are architectural styles that are cornerstones of
modern applications and cloud computing. Both aim to deliver scalable, interoperable
solutions, but their different roots don’t always make them a natural fit. SOA with REST
explains how the two styles can work together in enterprise environments. It discusses
a design process for a services portfolio that meets the goals of SOA and at the same
time designs services that comply with the established REST constraints. It also shows
pragmatic approaches to meet enterprise-grade requirements with the REST program-
ming style but relaxes constraints where necessary.”
—Christoph Schittko, Director of Cloud Strategy, Microsoft
“An inspirational book that provides deep insight into the design and development of
next-generation service-oriented systems based on the use of REST. This book clarifies
the convergence of SOA and REST with no-nonsense content that addresses common
questions and issues head-on. An essential ‘instrument of modern service imple-
mentation’ and a powerful body of knowledge for software designers, architects, and
consultants.”
—Pethuru Raj, Ph.D., Enterprise Architecture (EA) Consultant, Wipro Consulting Services
“The Service Technology Series from Thomas Erl continues its tradition of using simple
examples to elucidate complicated concepts. With the latest in the series, SOA with REST,
the authors have created a resource that discusses REST through the lenses of the com-
mon SOA pattern language. SOA with REST is a fantastic resource for the enterprise
architect and developer alike!”
—Kevin P. Davis, Ph.D., Software Architect
“Unlike many other texts on the subject, SOA with REST is a well-rounded, easy-to-read
narrative, including real-world case studies that appeal to both developers and analysts.
This makes it an indispensable source for any SOA practitioner or any professional who
is planning to initiate an SOA project.”
—Theodore T. Morrison, Certified SOA Analyst, CSM, Geocent, LLC
“The book is a must-read for any IT architect or software engineer who wants to gain a
deep understanding of the principles, patterns, and implementation concepts that per-
tain to building REST-based applications for service-oriented architectures. It goes well
beyond fundamental topics to explore the relationship between REST and various spe-
cific SOA principles and patterns.”
—Sanjay Singh, Certified SOA Architect, Development Manager, NorthgateArinso
“An authoritative, well-written reference for enterprise architects, analysts, developers,
and others. This book shows not only the elegance, simplicity, and versatility of REST,
it also gives us a clear understanding of how REST synergizes with SOA and service-
orientation, how REST can impact SOA design goals, how we can design and develop
REST services, and how we can address the unique challenges of integrating REST-
fulness into service-orientation. This book is required reading for anyone who desires
technical mastery of building service-oriented architectures with REST.”
—Philip Wik, MSS Technology
“This is a comprehensive and fundamental book to understand how to employ REST in
service-oriented architectures. The many examples provided and the patterns described
will be an invaluable help to any practitioner interested in service orientation.”
—Gustavo Alonso, Department of Computer Science, ETH Zurich
“SOA and REST are two very important architectural styles for distributed computing.
SOA is successfully adopted by most enterprises, and the REST style is getting more
attention from both researcher and industry users. The book SOA with REST introduces
a new architectural style that is ingeniously combining both SOA and REST styles and
clearly reveals how SOA and REST can work together to generate successful enter-
prise SOA strategies with REST, along with guidance for making architecture design
decisions. This book is a bible of best practices for designing and implementing SOA
architecture with REST. It is a must-have reference book for both IT practitioners and
researchers.”
—Longji Tang, FedEx IT Senior Technical Advisor, Ph.D. in CSSE
“REST and SOA are two of the most misunderstood terms in the software industry over
the past decade. Yet the REST architectural style coupled with modern RESTful frame-
work implementations provides a scalable and reliable approach to SOA. This book cov-
ers all you need to know about how to take the principles of REST and apply them in
small and large SOA developments. If you are familiar with REST and thinking about
SOA, then you need this book. If you have not considered REST in your SOA work, then
this book is for you, too. Covering concepts of both REST and SOA, as well as design
patterns and when to use them, the book is a wonderful companion and a good tool for
architects and engineers.”
—Dr. Mark Little, CTO JBoss, Red Hat
“This book is an excellent introduction into how SOA methodology can be used with
services implementing a RESTful architectural style. Thomas Erl and his co-authors
help SOA architects to better understand the implications of utilizing and the require-
ments for integrating REST into the service-oriented architecting process.”
—Gerald Beuchelt, MITRE
SOA with REST
The Prentice Hall Service Technology Series
from Thomas Erl aims to provide the IT industry with
a consistent level of unbiased, practical, and
comprehensive guidance and instruction in the areas
of service technology application and innovation.
Each title in this book series is authored in relation to
other titles so as to establish a library of complementary
knowledge. Although the series covers a broad spectrum
of service technology-related topics, each title is authored
in compliance with common language, vocabulary, and
illustration conventions so as to enable readers to
continually explore cross-topic research and education.
For more information, visit www.servicetechbooks.com.
SOC_Series_rev06-12.indd 1 7/1/12 12:26 PM
SOA with REST
Principles, Patterns & Constraints
for Building Enterprise Solutions with REST
thomas erl, Benjamin carlyle,
cesare pautasso, and raj Balasubramanian
PREnTicE HAll
Upper Saddle river, NJ • BoStoN • iNdiaNapoliS • SaN FraNciSco
New York • toroNto • MoNtreal • loNdoN • MUNich • pariS • Madrid
cape towN • SYdNeY • tokYo • SiNgapore • Mexico citY