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`Samw. 3‘-—’e-wt?
`
`Kenn Scribner
`
`Mark C. Stivevr
`
`egrviices
`MLWebS
`
`
`
`2.
`
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`
`Q I
`
`’
`
`Ing
`
`APP
`
`Imp
`
`001
`
`001
`
`SERVICENOW INC.'S EXHIBIT 1007
`
`

`
`
`
`Applied SIJAP: Implementing
`.NET XML WEI] Services
`
`
`
`Kenn Scribner and Mark C. Stiver
`
`sAMs
`
`201 West I03rd St., Indianapolis, Indiana, 46290
`
`002
`
`‘ SERVICENOW lNC.'S EXHIBIT 1007
`
`002
`
`SERVICENOW INC.'S EXHIBIT 1007
`
`

`
`Applied SOAP: Implementing
`.NET XML Web Services
`
`Copyright © 2002 by Sams Publishing
`All rights reserved. No part of this book shall be reproduced, stored in a
`retrieval system, or transmitted by any means, electronic, mechanical, photo-
`copying, recording, or otherwise, without written permission from the pub-
`lisher. No patent liability is assumed with respect to the use of the information
`contained herein. Although every precaution has been taken in the preparation
`of this book, the publisher and author assume no responsibility for errors or
`omissions. Nor is any liability assumed for damages resulting from the use of
`the information contained herein.
`
`International Standard Book Number: 0-672-32111-4
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`Library of Congress Catalog Card Number: 00-110536
`Printed in the United States of America
`
`First Printing: October 2001
`
`04
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`02
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`01
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`4
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`3
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`2
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`1
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`Trademarks
`
`All terms mentioned in this book that are known to be trademarks or service
`marks have been appropriately capitalized. Sams Publishing cannot attest to
`the accuracy of this information. Use of a term in this book should not be
`regarded as affecting the validity of any trademark or service mark.
`
`Windows, Windows 2000, Windows XP, .NET, Visual Studio .NET, .NET
`Framework, Passport, and Hailstorm are registered trademarks of Microsoft
`Corporation.
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`
`Warning and Disclaimer
`Every effort has been made to make this book as complete and as accurate as
`possible, but no warranty or fitness is implied. The information provided is on
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`responsibility to any person or entity with respect to any loss or damages aris-
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`:.»‘;;::°:.«;;..<,E-'_,
`
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`
`W4....;;:L__-.,,_§*.-51».3;‘:;3eTf'._Q',;._._.;‘.t).
`~—-—%»+:—‘..
`
`
`...,,.,V'3-.__.__¢‘Lag’.._,
`
`K...
`,..';.:;
`
`
`
`003
`
`SERVICENOW |NC.'S EXHIBIT 1007
`
`IV
`
`003
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`SERVICENOW INC.'S EXHIBIT 1007
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`

`
`
`
`Overview
`
`Introduction
`
`1
`
`>
`
`4;
`
`PART I
`
`Foundations of Web Services
`
`Web Service Fundamentals
`
`9
`
`UI-I>UJl\)
`
`.NET Architecture and Web Services Components
`Web Services and XML 75
`
`49
`
`.NET Web Services and SOAP
`
`123
`
`Web Service Description and Discovery
`
`163
`
`PART II
`
`Implementing Web Services
`Web Services in ASP.NET 193
`
`Consuming .NET Web Services
`
`245
`
`More Advanced Web Services
`
`.NET Remoting
`
`287
`
`Extreme Web Services
`
`301
`
`.NET and Web Service Security
`
`329
`
`PART IV
`
`Appendixes
`
`COW
`
`Example .NET Web Service
`
`357
`
`Using ATL Server to Create Web Services
`
`373
`
`XML Protocol and SOAP 385
`
`.NET Web Service Resources
`
`395
`
`Index
`
`401
`
`004
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`SERVICENOW |NC.'S EXHIBIT 1007
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`SERVICENOW INC.'S EXHIBIT 1007
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`

`
`Contents
`
`Introduction
`
`1
`
`PART I
`
`Foundations of Web Services
`
`-3
`
`9
`Web Service Fundamentals
`What Are Web Services? .................................................................... ..1O
`The Poor Man’s Web Service ........................................................ ..10
`
`
`
` '!§.‘¥.".._,_--.§‘A,5;._'Z'’_'_..‘%
`
`
`
`
`
`
`_._..6’A},-:1',""'IQ:-i‘r.C2f's'__-.._._‘.*‘
`
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`,,_,“'.k’
`
`...,A
`
`_.;::Af’
`
`
`7‘V L.£-,-.._E4
`
`
`FE:
`
`XML Messages .............................................................................. .. 13
`Syntax Versus Semantics ................................................................ ..13
`Web Service Terminology .............................................................. ..14
`The Road to Web Services .................................................................. ..l5
`Waves of the Internet ...................................................................... ..15
`Internet Standards .......................................................................... .. 16
`Uses for Web Services ........................................................................ ..2l
`Business-to-Business ...................................................................... ..21
`
`Exposing Functionality to Customers ............................................ ..22
`Integrating Heterogeneous Systems .............................................. ..23
`Rapid Development Environment .................................................. ..23
`Web Service Properties ........................................................................ ..24
`Performance .................................................................................... ..24
`
`Simplicity ...................................................................................... ..26
`Security .......................................................................................... ..26
`Reliability and Availability ............................................................ ..27
`Consistency .................................................................................... ..27
`Creating a Web Service in Visual Studio .NET .................................. ..28
`Creating the Service ............................................ .L ........................ ..28
`Creating the Client.......................................................................... ..32
`Tracing Messages on the Network ......................................... ..38
`Interface Design Tips ............................................................... ..40
`Learning from the Past ....................................................... ..40
`What Is an Interface? ........................................................... ..41
`Using SOAP to Encode Information ................................... ..42
`Interface Versioning ...................................................... ..
`....42
`Interface Complexity ........................................................... ..
`....45
`Summary .............................................................................................. ..48
`
`
`
`49
`.NET Architecture and Web Services Components
`Motivation for Creating .NET ............................................................ ..5O
`The Benefits and Limits of COM .................................................. ..50
`Other Microsoft Technology Considerations ................................ ..51
`n
`A Better Model .............................................................................. ..52
`
`005
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`
`
`The .NET Framework ..................................................................... ..53
`The Common Language Runtime ...................................... ..53
`Microsoft Intermediate Language ....................................... ..54
`Just-in-Time Compiling ................................................ ..57
`Common Type System ............................................................ ..58
`Assemblies and Managed Code . . . . . .
`. . . . . . . . . . . . . . . . . . . . . . . . . . . . ..67
`Security ............................................................................... ..68
`The System Namespace ................................................ ..68
`Web Services ...................................................................... ..73
`Discovery ................................................................... ..73
`Description........................................................................... ..73
`Protocols .......................................................................... ..74
`Summary .............................................................................................. ..74
`
`
`
`
`
`3 Web Services and XML
`
`75
`
`XML as a Wire Representation .......................................................... ..76
`XML and Loose Coupling .............................................................. ..78
`XML and Interoperability .............................................................. ..78
`Querying XML Elements Using XPath .............................................. ..79
`Essential XML .................................................................................... ..80
`Documents, Elements, and Attributes ............................................ ..80
`Entity References and CDATA ...................................................... ..83
`URIs and XML Namespaces .............................................................. ..84
`URLs and URNs ............................................................................ ..84
`XML Namespaces .................................................................. ..
`....85
`XML Schemas ............................................ ..
`....87
`
`....87
`Understanding XML Schemas .............. ..
`.NET Web Services and XML Schemas ................................ ..92
`XPath Drilldown .......................................................... ..93
`XPath Operators ..... ..
`................ ..96
`XPath Intrinsic Functions ............................................ ..97
`
`
`
`Identifying XML Elements Using XLink................................. ..99
`XML Transformations ........................................................ ..l01
`XSLT Drilldown ............................................................... ..102
`
`XSL Templates .......................................................... .. 106
`.NET’s XML Architecture .............................................. ..107
`
`Reading XML Data ........................................................ ..107
`Writing XML Data ........................................................... ..108
`Navigating XML with .NET ........................................................ ..1 12
`Pulling XML Element Information with .NET ............................ ..1 13
`.NET and XPath .......................................................................... ..114
`.NET and XLink .......................................................................... ..1 17
`.NET and XSL .............................................................................. ..118
`
`Summary ............................................................................................ ..120
`
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`i
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`vi
`
`APPLIEDEBXPI IMPLEMENTING .NMiEu:PY'|\/ii>|.:”\‘I_\M/‘EB SERVICES ‘
`
`4
`
`.NET Web Services and SOAP
`
`123
`
`Why Is SOAP Needed? ......................................................................124
`Why Do You Need to Understand SOAP?
`.................... ..l25
`The SOAP Advantage .............................................................. ..126
`The SOAP XML Object Model .................................................... ..l27
`The SOAP Envelope .......................................................................... ..127
`
`SOAP encodingstyle Attribute ........................................... ..128
`The SOAP Header ............................................................................ ..129
`SOAP Header Attributes .............................................................. ..13l
`
`
`
`The SOAP Body ................................................................................ ..133
`SOAP Body Serialization Terminology ...................................... ..l34
`SOAP Body Attributes .................................................................. .. 136
`SOAP Remote Method Serialization ............................................ ..137
`
`SOAP Serialization of Simple Datatypes .................................... ..140
`SOAP Serialization of Compound Data Types ............................ ..145
`SOAP struct Serialization ............................................................ ..145
`
`SOAP Array Serialization ............................................................ ..148
`SOAP Faults ................................................................................ ..153
`.NET SOAP Classes .......................................................................... ..155
`
`The .NET soapFormatter Class .................................................. ..155
`.NET SOAP Framing Classes ...................................................... ..159
`Summary ............................................................................................ .. 160
`
`,.w—,z_q__'«
`
`,_______§Ga. -\.
`D.,1"‘“°‘'''.9§.$L~r'_
`
`
`
`':’_‘fi.0_'f
`
`163
`5 Web Service Description and Discovery
`Web Service Description Language .................................................. ..l64
`The Abstract and the Concrete .... ..
`
`The Client’s Point of View ................................... ..
`
`Universal Description, Discovery, and Integration ............ ..
`What Is UDDI? ............................................................ ..
`How UDDI Works
`
`UDDI and Security .... ..
`tModels ...................... ..
`
`.
`
`.
`
`.
`
`
`
`. . . . . ..
`
`. . . . . . .
`Query Patterns . . . . . . . . . .
`Browsing ....................... ..
`Drilling Down .... ..
`Invoking ..................... ..
`. . . . . . .
`Publishing . . . . . . . . . . . . . . . . . . . . . . .
`. . . . . ..
`. . . . . . .
`Private Operations . . . . . . . . . . .
`Summary ............................................................................................ .. 190
`
`. . . . . ..
`
`007
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`

`
`EKONIFENTS
`
`Implementing Web Services
`
`Web Services in ASP.NET
`
`193
`
`Web Service Processing in .NET ...................................................... ..194
`ASP.NET Web Service Architecture ............................................ ..195
`.NET Remoting Versus .NET Web Services ................................ ..195
`Web Services and Visual Studio .NET .............................................. ..l97
`
`The Visual Studio Web Service Project........................................ ..197
`Moving Away from “Hello World” .............................................. ..199
`The WebMethod Attribute .............................................................. ..203
`Controlling the SOAP Serialization Format ...................................... ..205
`SOAP Method Attributes .............................................................. ..205
`Data Shaping ................................................................................ ..209
`Further Web Service SOAP Packet Customizations .................... ..213
`
`Adding SOAP Headers ...................................................................... ..222
`Header Processing ........................................................................ ..222
`Specifying SOAP Header Direction ............................................ ..224
`Additional SOAP Headers ............................................................ ..225
`
`Adding a SOAP Extension ................................................................ ..225
`Extension Stream Processing ...................................................... ..225
`Modifying the XML .................................................................... ..231
`Errors and the SOAP Fault ............................................................ ..231
`
`Default .NET SOAP Fault Processing ........................................ ..232
`Customized SOAP Faults Using SoapException ........................ ..232
`Web Service State Management ................................................. ..232
`
`. . . . . ..236
`Debugging and Deployment . . . . . . . . . . .
`. .
`. .
`. . . . . . . . . . . . . .
`Debugging ............................................................... ..236
`.NET Web Service Deployment ................................... ..238
`Web Services and Best Practices . . . . . . . . . .
`. . . . . . . . . . . . . .
`. . . . . . . . ..242
`
`
`
`Summary ............................................................................................ ..243
`
`245
`Consuming .NET Web Services
`Visual Studio .NET Web Service Support ........................................ ..246
`Consuming Web Services .................................................................. ..248
`Creating the Web Reference ........................................................ .253
`Web Service Configuration Files .................................................. ..268
`SOAP Headers .................................................................................. ..27l
`
`Intercepting and Modifying SOAP Packets ...................................... ..273
`More Deployment and Debugging .................................................... ..283
`Summary ............................................................................................ ..283
`
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`

`
`
`
`.
`APPLIED SOAP: IMPLEMENTING .NET XML WEB SERVICES
`
`PART III More Advanced Web Services
`8
`.NET Remoting
`237
`.NET Remoting Architecture ..............................................................288
`Remoting Boundaries .................................................................. .289
`Remoting Object Model ................................................................290
`Remoting Channels ........................................................................291
`Remotable Objects ..............................................................................292
`Serializable Objects ........................................................................292
`Marshaling Objects by Reference ..................................................293
`Object Lifetimes .......................................................................... ..294
`Configuring .NET Remoting ..........................................................296
`.NET Remoting Example ....................................................................297
`Summary ............................................................................................ ..299
`Extreme Web Services
`301
`. . . . . . . . . . . . ..302
`. . . . . . .
`Embedded XML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
`Entity References.................................................... ..302
`CDATA Sections .............................................................303
`base64 Encoding .......................................................................... ..304
`Rich XML Messaging .................................................................. ..308
`SOAP Messages with Attachments ................................................310
`SOAP and Attachments .................................................................... ..311
`Direct Internet Message Encapsulation (DIME) .......................... ..313
`Transactions ...................................................................................... ..3 13
`Transaction Authority Markup Language (XAML) .................... ..314
`Applying Transactions to Web Services ...................................... ..314
`Debugging and Web Services ..............................................................315
`Web Service Documentation ..............................................................318
`Overview ...................................................................................... ..3l9
`Design Approach ............................................................................319
`API Summary .............................................................................. ..322
`API Reference ................................................................................322
`Data Structures ............................................................................ .323
`Error Reference ..............................................................................324
`Test Environment .......................................................................... ..324
`Sample Document ........................................................................ ..324
`Summary ..............................................................................................327
`.NET and Web Service Security
`329
`Security Terms and Concepts ..............................................................33O
`Application-Level Security Versus System-Level Security .............. ..332
`Web Services and Security ................................................................ ..332
`Breadth of Web Service Security ...................................................... ..333
`Intranet Web Service Security Alternatives ....................... .... ....... ..333 ‘
`Internet Web Service Security Alternatives .................................. ..339
`
`9
`
`10
`
`
`
`
`009
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`SERVICENOW lNC.'S EXHIBIT 1007
`
`
`
`" T
`Q‘
`{
`
`. I
`‘
`4',‘
`2 i
`i
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`‘
`
`
`
`009
`
`SERVICENOW INC.'S EXHIBIT 1007
`
`

`
`
`
`.NET Security .................................................................................... ..353
`
`.NET Evidence-Based Security .................................................... ..354
`COM+ Security ............................................................................ ..356
`Summary ............................................................................................ ..356
`
`PART IV
`
`Appendixes
`
`Example .NET Web Service
`
`359
`
`Tip of the Day Web Service in Visual Basic .NET .......................... ..360
`finger Web Service in C# ................................................................ ..367
`
`375
`Using ATL Server to Create Web Services
`ATL Server Architecture .................................................................... ..376
`Attributed C++.............................................................. ..
`....377
`When to Select ATL Server ........................................... ..
`....380
`
`Example ATL Server Web Service ..................................... ..
`
`XML Protocol and SOAP
`
`387
`
`
`
`....381
`
`The Birth of XML Protocol .............................................................. ..388
`The XMLP Abstract Model . . . . .
`. . . . . . . . . ..388
`Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . .
`. . . . . . . . . ..388
`
`
`
`An XMLP Walkthrough .............................................................. ..390
`XMLP_UnitData ........................................................................ ..391
`SOAP v1.2 ........................................................................................ ..394
`
`No More Simple Object Access Protocol .................................... ..394
`Bindings ........................................................................................ ..394
`Namespace URIS .......................................................................... ..394
`encodingSty1e .............................................................................. ..395
`mustUnderstand Faults ................................................................ ..395
`
`XMLP, SOAP, and the Future ............................................................ ..396
`
`397
`.NET Web Service Resources
`XML General .................................................................................... .398
`General .NET Information ................................................................ ..398
`General Web Service Information .................................................... ..399
`SOAP/XML Protocol ........................................................................ ..399
`
`. . . . . . . . . . . . . . . . . . . . . . . ..399
`Remoting . . . . . . . . . . . . . . . . . . . . .
`. . . . . . . . . . . . . . . . . . . . . . . ..400
`UDDI. . . . . . . . . . . . .
`. - - - . .-400
`WSDL . . . . . . . . . . . . . . . . . .
`. . . . . ..400
`Transactions . . . . . . . . . . . . . . . . . . .
`Tools ........................................................................................... ..40O
`
`
`
`Security .............................................................................................. ..400
`ebXML .............................................................................................. ..401
`
`Sample Web Service .......................................................................... ..401
`
`Index
`
`403
`
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`

`
`Web Service Fundamentals
`
`IN THIS CHAPTER
`
`0 What Are Web Services?
`
`10
`
`0 The Road to Web Services
`
`15
`
`0 Uses for Web Services
`
`21
`
`0 Web Service Properties
`
`24
`
`v Creating a Web Service in
`
`Visual Studio .NET 28
`
`0 Interface Design Tips
`
`40
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`

`
`It’s pretty hard to pick up a trade magazine these days without seeing a headline about Web
`Services. With phrases such as “a new paradigm" being proliferated, are we really witnessing
`the genesis of a new technology?
`
`Unfortunately, the answer isn’t black and white—a lot depends on your perspective. Web
`Services can be used in a wide variety of ways, including these:
`
`- Participating in business—to-business (B2B) transactions
`
`0 Exposing software functionality to customers
`
`-
`
`Integrating heterogeneous platforms and programming languages
`
`- Providing a simplified platform for product development
`
`What Are Web Services?
`
`Web Services can be described as any functionality that is accessible over the Internet, gener-
`ally (but not necessarily) using one or more eXtensible Markup Language (XML) messages in
`the communications protocol- Web Services use the concept of an operation to represent the
`association of a request message to zero or more response messages. When these operations
`are combined to satisfy some particular purpose, they form an interface.
`
`The Poor Man's Web Service
`
`The Internet is already flooded with conventional types of Web Services, better known as Web
`pages. Users are expected to interact with the functionality behind the Web page through typi-
`cal user—interface widgets such as forms, buttons, and so on.
`
`We already know how to reuse Web functionality by embedding other Web pages into our own
`pages through frames and links. But this presentation—based approach severely limits the things
`that you can accomplish. If you embed another Web site within a frame of your own, you gen-
`erally have no control over the colors, graphics, or other aspects of the presentation. Another
`problem is that any information entered by a user in the embedded page never gets back to
`your controlling application. In other words, you’re out of the loop!
`
`One way around this is for your application to act as a proxy for the user. Many developers
`have already written simple applications that navigate to a particular URL, screen-scrape the
`Web site’s HTML for information, and use that information to build new Web content.
`
`Consider the following HTML that describes the current weather temperature:
`
`<HTML>
`
`<HEAD>
`
`<TITLE>Today's Wea1:her<{TITLE>
`<,'HEAD>
`<BODY>
`
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`
`
`
`S'IV.l.NEllA|VClNl'l;|
`
`EDIAHSSHEM
`
`Web Service Fundamentals
`
`U
`
`CHAPTER 1‘
`
`<P>City: <B>Los Angeles<!B><!P>
`<P>State: <B>Ca1ifornia<!B><fP>
`
`<P>Temperature: <B>83<fB><!P>
`<fBODY>
`
`<!HTML>
`
`In this case, it would be fairly simple to programmatically locate the temperature value within
`the markup. However, over an extended period of time using this service, you can be sure that
`the underlying Web page will change and ultimately break your application. It would be nearly
`impossible to develop software that could automatically adjust to fluctuations in the type of
`markup, as shown:
`
`<HTML>
`
`<HEAD>
`
`<TITLE>Today's Weather<iTITLE>
`<!HEAD>
`<BODY>
`
`<TABLE wIDTH="500” CELLPADDING=“1@" CELLSPACING=“15">
`<TR>
`
`<TD ALIGN="LEFT" VALIGN%“MIDDLE" WIDTH=“1@@"><B>city<lB><!TD>
`<TD ALIGN="LEFT" VALIGN="MIDDLE" WIDTH=“2@0“>Los Ange1es<!TD>
`<lTR>
`<TR>
`
`<TD ALIGN="LEFT” VALIGN="MIDDLE“ WIDTH=“1@@"><B>8tate<!B><lTD>
`
`<TD ALIGN="LEFT“ VALIGN="MIDDLE“ WIDTH="2@@“>Ca1ifornia<!TD>
`<{TR>
`<Tn>
`
`<TD ALIGN="LEFT" VALIGN=“MIDDLE" wIDTH="1@@">
`
`<B>Temperature<lB>
`<;Tn>
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`<TD ALIGN="LEFT" VALIGN=“MIDDLE“ WIDTH=“20@“>83<!TD>
`<TD ALIGN="LEFT" VALIGN="TOP“>
`
`<IMG SRC=“sunny.gif“ WIDTH="25" HEIGHT=“33“>
`<!TD>
`
`<lTR>
`
`<lTABLE>
`
`</BODY>
`
`<rHTML>
`
`Now consider integrating multiple systems using this approach. Recall that in the Web Services
`paradigm, many systems likely could participate in some business process. Because HTML
`content changes at such a fast pace, you likely will not ever be able to construct a reliable inte-
`
`grated solution.
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`For example, consider one application that monitors the temperature Web site and another Web
`
`site that posts the average speed of traffic on a nearby highway:
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`<HTML>
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`<HEAD>
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`<TITLE>Interstate Traffic Report<!TITLE>
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`<!HEAD>
`<BODY>
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`<CENTER>Average Speed<!CENTER>
`<CENTER>67<iCENTER>
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`<!BODY>
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`<!HTML>
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`By relating these two axes of data, the application might be capable of determining whether
`there is a correlation between sunny days and fast driving. Although it might be an interesting
`problem to solve, the likelihood of the application working with 24x? reliability is extremely
`low. The plain-and-simple fact is that relying on presentation-oriented data leads to a tightly
`coupled and brittle system.
`
`The question isn’t whether the concept of integrating Web content is valid; the problem lies
`within the information that can be obtained from a source. Without rich content markup, pro-
`grams don’t have much of a chance of locating pertinent information. Of course, this is where
`XML markup makes an important difference. Given standardized markup that describes infor~
`mation in a particular domain space, an application should always be capable of finding the
`
`right data.
`
`Taking the concept of standardized markup into account, Web Services can be better defined as
`functionality that is accessed over the Web and that provides infonnation in a reliable and pre-
`dictable manner. In many cases, this predictability will be realized through the use of XML
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`markup for describing information.
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`Although Web Services are not limited to the following technologies, you will find that a large
`percentage of Web Service implementations are built upon the Hypertext Transfer Protocol
`(HTTP), SOAP/XML as a messaging protocol, and Web Services Description Language
`
`(WSDL) as a way to describe service interfaces.
`
`The basic idea behind Web Services isn’t really new. in many ways, we are just reusing tech-
`nologies that most of us have used for years. Surprisingly, many developers have already built
`systems using Web Service techniques, but in a very ad hoc and proprietary way. The main
`difference is that the industry is now supporting Web Services with standards, tools, and
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`implementations.
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`First reactions about Web Services usually revolve around performance. Most people recognize
`that transmitting XML is not the most expeditious way for systems to communicate. So why
`use XML? We use XML because it provides us with a predictable way to package information
`that is structured, extensible, and yet still very easy to use—not something that can be said for
`
`other packaging protocols. Let’s take a closer look.
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`Web Service Fundamentals
`CI.-lA|-’TER _
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`XML Messages
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`By nature, interface-based programming enables us to build loosely coupled systems, meaning
`that the client and Web Service are independent of one another. This has been true in object-
`oriented programming for many years, within the confines of a particular programming language.
`Web Services reinforce loosely coupled systems by removing dependence upon a common
`programming language or even a common platform. This is realized through the use of XML
`messages, which define the operatio