|I have been a fan of the Martin Fowler Signature Series for a long time. This book fit into the series great and filled in a missing link in the series.
One of the things I liked seeing was that the author does not think web services are a silver bullet. Right off the bat he warns that web services should be reserved for situations which out-of-process and cross-machine calls "make sense".
The book is broken down into seven chapters, an appendix, and a nice glossary. The chapters include From Objects to Web Services, Web Service API Styles, Client-Service Interactions, Request and Response Management, Web Service Implementation Styles, Web Service Infrastructures, Web Service Evolution, and an appendix Reference to External Patterns.
I felt the book worked at the right level of abstraction digging into details when needed to shed a deeper light on the subject at hand.
Each chapter contains several related patterns. Each pattern answers a primary question. For example chapter one Web Service API Styles cover the following 3 patterns that answer the question that follows below.
RPC API - How can clients execute remote procedures over HTTP?
Message API - How can clients send commands, notifications, or other information to remote systems over HTTP while avoiding direct coupling to remote procedures?
Resource API - How can a client manipulate data managed by a remote system, avoid direct coupling to remote procedures, and minimize the need for domain-specific APIs?
The other patterns covered in the book include Request/Response, Request/Acknowledge, Media Type Negotiation, Linked Service, Service Controller, Data Transfer Object, Request Mapper, Response Mapper, Transaction Script, Datasource Adapter, Operation Script, Command Invoker, Workflow Connector, Service Connector, Service Descriptor, Asynchronous Response Handler, Service Interceptor, Idempotent Retry, SOA Infrastructures, Breaking Changes, Versioning, Single Message Argument, Dataset Amendment, Tolerant Reader, and Consumer-Driven Contract.
Like the other pattern catalogs the book contains an online catalog of the patterns in the book. Although the online catalog gives you an overview of each pattern, the book contains a lot more detail about each one. I like the online catalogs. I often visit them to spark my memory about the patterns that I have read about in the books.
I like that the book limited its scope to the fundamental patterns relevant to web service design. It does not try to be all encompassing, which I think made it better than if the author had tried to be. The book does not cover enterprise integration patterns, workflow or orchestration, security, event-driven architecture, or choreography. The book does include a nice reference to external patterns in the appendix that provides a summary and where to go for more information.
I think each pattern is explained really well and the examples used do a great job of showing a possible implementation. I liked the end of chapter 7 where the author provides a nice summary about how each pattern hinders or promotes evolution.
The book also includes a nice glossary that provides quick reference to additional information on topics mentioned in the book.
The author does an awesome job of providing examples in different technologies throughout the book. The author uses a nice mixture of .NET and Java technologies. Some of the technologies used are JAX-WS, JAX-RS, JAXB, JSON, XML, Xpath, XSLT, WSDL, DataContractSerializer, XmlSerializer, and WCF. To top it off the author's writing style makes the reading really easy.
All in all I think every architect and developer should have this book on their shelf.
Service Design Patterns: Fundamental Design Solutions for SOAP/WSDL and RESTful Web Services