kevin Mocha - Research | WS http://blog.ilovedoudou.com/ Bookmarks collected from web. en-us Kevin Mocha Mon, 24 Mar 2008 15:22:31 GMT newtelligence dasBlog 1.9.6264.0 lulustock@gmail.com lulustock@gmail.com http://blog.ilovedoudou.com/Trackback.aspx?guid=3b43b326-0ef9-4bd5-ac16-d46a537d9a93 http://blog.ilovedoudou.com/pingback.aspx http://blog.ilovedoudou.com/PermaLink,guid,3b43b326-0ef9-4bd5-ac16-d46a537d9a93.aspx Kevin Mocha http://blog.ilovedoudou.com/CommentView,guid,3b43b326-0ef9-4bd5-ac16-d46a537d9a93.aspx http://blog.ilovedoudou.com/SyndicationService.asmx/GetEntryCommentsRss?guid=3b43b326-0ef9-4bd5-ac16-d46a537d9a93

http://www.xfront.com/REST-Web-Services.html

What is REST?

REST is a term coined by Roy Fielding in his Ph.D. dissertation [1] to describe an architecture style of networked systems. REST is an acronym standing for Representational State Transfer.

REST - An Architectural Style, Not a Standard

REST is not a standard. You will not see the W3C putting out a REST specification. You will not see IBM or Microsoft or Sun selling a REST developer's toolkit. Why? Because REST is just an architectural style. You can't bottle up that style. You can only understand it, and design your Web services in that style. (Analogous to the client-server architectural style. There is no client-server standard.)

While REST is not a standard, it does use standards:

  • HTTP
  • URL
  • XML/HTML/GIF/JPEG/etc (Resource Representations)
  • text/xml, text/html, image/gif, image/jpeg, etc (MIME Types)

The Classic REST System

The Web is a REST system! Many of those Web services that you have been using these many years - book-ordering services, search services, online dictionary services, etc - are REST-based Web services. Alas, you have been using REST, building REST services and you didn't even know it.

REST is concerned with the "big picture" of the Web. It does not deal with implementation details (e.g., using Java servlets or CGI to implement a Web service). So let's look at an example of creating a Web service from the REST "big picture" perspective.

REST Web Services Characteristics

Here are the characteristics of REST:
  • Client-Server: a pull-based interaction style: consuming components pull representations.
  • Stateless: each request from client to server must contain all the information necessary to understand the request, and cannot take advantage of any stored context on the server.
  • Cache: to improve network efficiency responses must be capable of being labeled as cacheable or non-cacheable.
  • Uniform interface: all resources are accessed with a generic interface (e.g., HTTP GET, POST, PUT, DELETE).
  • Named resources - the system is comprised of resources which are named using a URL.
  • Interconnected resource representations - the representations of the resources are interconnected using URLs, thereby enabling a client to progress from one state to another.
  • Layered components - intermediaries, such as proxy servers, cache servers, gateways, etc, can be inserted between clients and resources to support performance, security, etc.

Principles of REST Web Service Design

1. The key to creating Web Services in a REST network (i.e., the Web) is to identify all of the conceptual entities that you wish to expose as services. Above we saw some examples of resources: parts list, detailed part data, purchase order.

2. Create a URL to each resource. The resources should be nouns, not verbs. For example, do not use this: 

http://www.parts-depot.com/parts/getPart?id=00345
Note the verb, getPart. Instead, use a noun: 
http://www.parts-depot.com/parts/00345
3. Categorize your resources according to whether clients can just receive a representation of the resource, or whether clients can modify (add to) the resource. For the former, make those resources accessible using an HTTP GET. For the later, make those resources accessible using HTTP POST, PUT, and/or DELETE.

4. All resources accessible via HTTP GET should be side-effect free. That is, the resource should just return a representation of the resource. Invoking the resource should not result in modifying the resource.

5. No man/woman is an island. Likewise, no representation should be an island. In other words, put hyperlinks within resource representations to enable clients to drill down for more information, and/or to obtain related information.

6. Design to reveal data gradually. Don't reveal everything in a single response document. Provide hyperlinks to obtain more details.

7. Specify the format of response data using a schema (DTD, W3C Schema, RelaxNG, or Schematron). For those services that require a POST or PUT to it, also provide a schema to specify the format of the response.

8. Describe how your services are to be invoked using either a WSDL document, or simply an HTML document.

http://www.infoq.com/articles/rest-introduction

Key REST principles

Most introductions to REST start with the formal definition and background. I’ll defer this for a while and provide a simplified, pragmatic definition: REST is a set of principles that define how Web standards, such as HTTP and URIs, are supposed to be used (which often differs quite a bit from what many people actually do). The promise is that if you adhere to REST principles while designing your application, you will end up with a system that exploits the Web’s architecture to your benefit. In summary, the five key principles are:
  • Give every “thing” an ID
  • Link things together
  • Use standard methods
  • Resources with multiple representations
  • Communicate statelessly
basic concepts of REST http://blog.ilovedoudou.com/PermaLink,guid,3b43b326-0ef9-4bd5-ac16-d46a537d9a93.aspx http://blog.ilovedoudou.com/PermaLink,guid,3b43b326-0ef9-4bd5-ac16-d46a537d9a93.aspx Mon, 24 Mar 2008 15:22:31 GMT <p> <a title="http://www.xfront.com/REST-Web-Services.html" href="http://www.xfront.com/REST-Web-Services.html">http://www.xfront.com/REST-Web-Services.html</a> </p> <h4>What is REST? </h4> REST is a term coined by Roy Fielding in his Ph.D. dissertation [1] to describe an <b>architecture style</b> of networked systems. REST is an acronym standing for Representational State Transfer. <h4>REST - An Architectural Style, Not a Standard </h4> REST is not a standard. You will not see the W3C putting out a REST specification. You will not see IBM or Microsoft or Sun selling a REST developer's toolkit. Why? Because REST is just an architectural style. You can't bottle up that style. You can only understand it, and design your Web services in that style. (Analogous to the client-server architectural style. There is no client-server standard.) <p> While REST is not a standard, it does use standards: <ul> <li> HTTP <li> URL <li> XML/HTML/GIF/JPEG/etc (Resource Representations) <li> text/xml, text/html, image/gif, image/jpeg, etc (MIME Types)</li> </ul> <h4>The Classic REST System </h4> The Web is a REST system! Many of those Web services that you have been using these many years - book-ordering services, search services, online dictionary services, etc - are REST-based Web services. Alas, you have been using REST, building REST services and you didn't even know it. <p> REST is concerned with the "big picture" of the Web. It does not deal with implementation details (e.g., using Java servlets or CGI to implement a Web service). So let's look at an example of creating a Web service from the REST "big picture" perspective. <h4>REST Web Services Characteristics </h4> Here are the characteristics of REST: <ul> <li> Client-Server: a pull-based interaction style: consuming components pull representations. <li> Stateless: each request from client to server must contain all the information necessary to understand the request, and cannot take advantage of any stored context on the server. <li> Cache: to improve network efficiency responses must be capable of being labeled as cacheable or non-cacheable. <li> Uniform interface: all resources are accessed with a generic interface (e.g., HTTP GET, POST, PUT, DELETE). <li> Named resources - the system is comprised of resources which are named using a URL. <li> Interconnected resource representations - the representations of the resources are interconnected using URLs, thereby enabling a client to progress from one state to another. <li> Layered components - intermediaries, such as proxy servers, cache servers, gateways, etc, can be inserted between clients and resources to support performance, security, etc.</li> </ul> <h4>Principles of REST Web Service Design </h4> 1. The key to creating Web Services in a REST network (i.e., the Web) is to identify all of the conceptual entities that you wish to expose as services. Above we saw some examples of resources: parts list, detailed part data, purchase order. <p> 2. Create a URL to each resource. The resources should be nouns, not verbs. For example, do not use this: <blockquote> <blockquote><pre>http://www.parts-depot.com/parts/getPart?id=00345 </pre> </blockquote>Note the verb, getPart. Instead, use a noun: <blockquote><pre>http://www.parts-depot.com/parts/00345 </pre> </blockquote></blockquote>3. Categorize your resources according to whether clients can just receive a representation of the resource, or whether clients can modify (add to) the resource. For the former, make those resources accessible using an HTTP GET. For the later, make those resources accessible using HTTP POST, PUT, and/or DELETE. <p> 4. All resources accessible via HTTP GET should be side-effect free. That is, the resource should just return a representation of the resource. Invoking the resource should not result in modifying the resource. <p> 5. No man/woman is an island. Likewise, no representation should be an island. In other words, put hyperlinks within resource representations to enable clients to drill down for more information, and/or to obtain related information. <p> 6. Design to reveal data gradually. Don't reveal everything in a single response document. Provide hyperlinks to obtain more details. <p> 7. Specify the format of response data using a schema (DTD, W3C Schema, RelaxNG, or Schematron). For those services that require a POST or PUT to it, also provide a schema to specify the format of the response. <p> 8. Describe how your services are to be invoked using either a WSDL document, or simply an HTML document. <p> <a title="http://www.infoq.com/articles/rest-introduction" href="http://www.infoq.com/articles/rest-introduction">http://www.infoq.com/articles/rest-introduction</a> </p> <h4>Key REST principles </h4> Most introductions to REST start with the formal definition and background. I’ll defer this for a while and provide a simplified, pragmatic definition: REST is a set of principles that define how Web standards, such as HTTP and URIs, are supposed to be used (which often differs quite a bit from what many people actually do). The promise is that if you adhere to REST principles while designing your application, you will end up with a system that exploits the Web’s architecture to your benefit. In summary, the five key principles are: <ul> <li> Give every “thing” an ID <li> Link things together <li> Use standard methods <li> Resources with multiple representations <li> Communicate statelessly </li> </ul> <img width="0" height="0" src="http://blog.ilovedoudou.com/aggbug.ashx?id=3b43b326-0ef9-4bd5-ac16-d46a537d9a93" /> http://blog.ilovedoudou.com/CommentView,guid,3b43b326-0ef9-4bd5-ac16-d46a537d9a93.aspx Research / WS http://blog.ilovedoudou.com/Trackback.aspx?guid=c111cf5a-e034-4b01-80cd-77d6520aa181 http://blog.ilovedoudou.com/pingback.aspx http://blog.ilovedoudou.com/PermaLink,guid,c111cf5a-e034-4b01-80cd-77d6520aa181.aspx Kevin Mocha http://blog.ilovedoudou.com/CommentView,guid,c111cf5a-e034-4b01-80cd-77d6520aa181.aspx http://blog.ilovedoudou.com/SyndicationService.asmx/GetEntryCommentsRss?guid=c111cf5a-e034-4b01-80cd-77d6520aa181

Introduction to workflow

http://en.wikipedia.org/wiki/Workflow

http://www.e-workflow.org/bookstore/introduction_to_workflow02.pdf

http://blogs.msdn.com/davegreen/archive/2005/09/17/470704.aspx

http://www.aboutworkflow.com/WorkflowTutorial/index.htm

http://www.sqldts.com/287.aspx

http://www.e-workflow.org/standards/index.htm

 

Workflow Control-Flow Patterns

http://www.workflowpatterns.com/documentation/documents/BPM-06-22.pdf

http://www.workflowpatterns.com/patterns/control/index.php

http://www.workflowpatterns.com/documentation/index.php

http://en.wikipedia.org/wiki/Workflow_patterns (Good)

 

BPEL

Is BPEL the same as BPM, workflow or integration?

http://searchwebservices.techtarget.com/ateQuestionNResponse/0,289625,sid26_cid565868_tax292928,00.html

Service-Oriented Architecture-Concepts, Technology, and Design (book)

web Services Platform Arthitecture - SOAP, WSDL, WS-Policy, WS-Addressing, WS-BPEL, (book)

 

 

Implementation

Deploy distributed business processes with windows workflow and web service

http://msdn.microsoft.com/msdnmag/issues/06/10/webserviceworkflows/

http://blogs.msdn.com/publicsector/archive/2005/10/27/485691.aspx

 

Orchestrating Web Service

http://www.ftponline.com/xmlmag/2002_06/magazine/focus/sjohnston/default.aspx

Orchestration and Choreography

Service-Oriented Architecture - Concepts, Technology, and Design

 

Business processes and workflow in the Web services world

http://www.ibm.com/developerworks/webservices/library/ws-work.html

Work Flow http://blog.ilovedoudou.com/PermaLink,guid,c111cf5a-e034-4b01-80cd-77d6520aa181.aspx http://blog.ilovedoudou.com/PermaLink,guid,c111cf5a-e034-4b01-80cd-77d6520aa181.aspx Thu, 20 Sep 2007 03:32:27 GMT <p> <strong>Introduction to workflow</strong> </p> <p> <a title="http://en.wikipedia.org/wiki/Workflow" href="http://en.wikipedia.org/wiki/Workflow">http://en.wikipedia.org/wiki/Workflow</a> </p> <p> <a title="http://www.e-workflow.org/bookstore/introduction_to_workflow02.pdf" href="http://www.e-workflow.org/bookstore/introduction_to_workflow02.pdf">http://www.e-workflow.org/bookstore/introduction_to_workflow02.pdf</a> </p> <p> <a title="http://blogs.msdn.com/davegreen/archive/2005/09/17/470704.aspx" href="http://blogs.msdn.com/davegreen/archive/2005/09/17/470704.aspx">http://blogs.msdn.com/davegreen/archive/2005/09/17/470704.aspx</a> </p> <p> <a title="http://www.aboutworkflow.com/WorkflowTutorial/index.htm" href="http://www.aboutworkflow.com/WorkflowTutorial/index.htm">http://www.aboutworkflow.com/WorkflowTutorial/index.htm</a> </p> <p> <a title="http://www.sqldts.com/287.aspx" href="http://www.sqldts.com/287.aspx">http://www.sqldts.com/287.aspx</a> </p> <p> <a title="http://www.e-workflow.org/standards/index.htm" href="http://www.e-workflow.org/standards/index.htm">http://www.e-workflow.org/standards/index.htm</a> </p> <p> &nbsp; </p> <p> <strong>Workflow Control-Flow Patterns</strong> </p> <p> <a title="http://www.workflowpatterns.com/documentation/documents/BPM-06-22.pdf" href="http://www.workflowpatterns.com/documentation/documents/BPM-06-22.pdf">http://www.workflowpatterns.com/documentation/documents/BPM-06-22.pdf</a> </p> <p> <a title="http://www.workflowpatterns.com/patterns/control/index.php" href="http://www.workflowpatterns.com/patterns/control/index.php">http://www.workflowpatterns.com/patterns/control/index.php</a> </p> <p> <a title="http://www.workflowpatterns.com/documentation/index.php" href="http://www.workflowpatterns.com/documentation/index.php">http://www.workflowpatterns.com/documentation/index.php</a> </p> <p> <a title="http://en.wikipedia.org/wiki/Workflow_patterns" href="http://en.wikipedia.org/wiki/Workflow_patterns">http://en.wikipedia.org/wiki/Workflow_patterns</a>&nbsp;(Good) </p> <p> &nbsp; </p> <p> <strong>BPEL</strong> </p> <h3>Is BPEL the same as BPM, workflow or integration? </h3> <p> <a title="http://searchwebservices.techtarget.com/ateQuestionNResponse/0,289625,sid26_cid565868_tax292928,00.html" href="http://searchwebservices.techtarget.com/ateQuestionNResponse/0,289625,sid26_cid565868_tax292928,00.html">http://searchwebservices.techtarget.com/ateQuestionNResponse/0,289625,sid26_cid565868_tax292928,00.html</a> </p> <p> Service-Oriented Architecture-Concepts, Technology, and Design (book) </p> <p> web Services Platform Arthitecture - SOAP, WSDL, WS-Policy, WS-Addressing, WS-BPEL, (book) </p> <p> &nbsp; </p> <p> &nbsp; </p> <p> <strong>Implementation</strong> </p> <p> Deploy distributed business processes with windows workflow and web service </p> <p> <a title="http://msdn.microsoft.com/msdnmag/issues/06/10/webserviceworkflows/" href="http://msdn.microsoft.com/msdnmag/issues/06/10/webserviceworkflows/">http://msdn.microsoft.com/msdnmag/issues/06/10/webserviceworkflows/</a> </p> <p> <a title="http://blogs.msdn.com/publicsector/archive/2005/10/27/485691.aspx" href="http://blogs.msdn.com/publicsector/archive/2005/10/27/485691.aspx">http://blogs.msdn.com/publicsector/archive/2005/10/27/485691.aspx</a> </p> <p> &nbsp; </p> <p> <strong>Orchestrating Web Service</strong> </p> <p> <a title="http://www.ftponline.com/xmlmag/2002_06/magazine/focus/sjohnston/default.aspx" href="http://www.ftponline.com/xmlmag/2002_06/magazine/focus/sjohnston/default.aspx">http://www.ftponline.com/xmlmag/2002_06/magazine/focus/sjohnston/default.aspx</a> </p> <p> Orchestration and Choreography </p> <p> Service-Oriented Architecture - Concepts, Technology, and Design </p> <p> &nbsp; </p> <h3>Business processes and workflow in the Web services world </h3> <p> <a title="http://www.ibm.com/developerworks/webservices/library/ws-work.html" href="http://www.ibm.com/developerworks/webservices/library/ws-work.html">http://www.ibm.com/developerworks/webservices/library/ws-work.html</a> </p> <img width="0" height="0" src="http://blog.ilovedoudou.com/aggbug.ashx?id=c111cf5a-e034-4b01-80cd-77d6520aa181" /> http://blog.ilovedoudou.com/CommentView,guid,c111cf5a-e034-4b01-80cd-77d6520aa181.aspx Research;Research / WS http://blog.ilovedoudou.com/Trackback.aspx?guid=353c0744-1f4a-4510-9c47-8ca1bfe3d879 http://blog.ilovedoudou.com/pingback.aspx http://blog.ilovedoudou.com/PermaLink,guid,353c0744-1f4a-4510-9c47-8ca1bfe3d879.aspx Kevin Mocha http://blog.ilovedoudou.com/CommentView,guid,353c0744-1f4a-4510-9c47-8ca1bfe3d879.aspx http://blog.ilovedoudou.com/SyndicationService.asmx/GetEntryCommentsRss?guid=353c0744-1f4a-4510-9c47-8ca1bfe3d879

http://www.ibm.com/developerworks/webservices/library/ws-work.html Jan, 2003

Business processes and workflow in the Web services world http://blog.ilovedoudou.com/PermaLink,guid,353c0744-1f4a-4510-9c47-8ca1bfe3d879.aspx http://blog.ilovedoudou.com/PermaLink,guid,353c0744-1f4a-4510-9c47-8ca1bfe3d879.aspx Mon, 17 Sep 2007 16:12:34 GMT <p> <a title="http://www.ibm.com/developerworks/webservices/library/ws-work.html" href="http://www.ibm.com/developerworks/webservices/library/ws-work.html">http://www.ibm.com/developerworks/webservices/library/ws-work.html</a>&nbsp;Jan, 2003 </p> <img width="0" height="0" src="http://blog.ilovedoudou.com/aggbug.ashx?id=353c0744-1f4a-4510-9c47-8ca1bfe3d879" /> http://blog.ilovedoudou.com/CommentView,guid,353c0744-1f4a-4510-9c47-8ca1bfe3d879.aspx Research;Research / WS