Module 7: Business Logic for Disconnected Components

Module 7: Business Logic for Disconnected Components Contents Overview 1 Introduction to Disconnected Business Logic 2 Technologies 7 Demonstration: Queued Components 11 Demonstration: COM+ Events 15 Logical Design of Disconnected Business Logic 19 Physical Design of Disconnected Business Logic 26 Market Purchasing 42 Best Practices 45 Lab 7: Business Logic for Disconnected Components 46 Review 54 Information in this document is subject to change without notice. The names of companies, products, people, characters, and/or data mentioned herein are fictitious and are in no way intended to represent any real individual, company, product, or event, unless otherwise noted. Complying with all applicable copyright laws is the responsibility of the user. No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written permission of Microsoft Corporation. If, however, your only means of access is electronic, permission to print one copy is hereby granted. Microsoft may have patents, patent applications, trademarks, copyrights, or other intellectual property rights covering subject matter in this document. Except as expressly provided in any written license agreement from Microsoft, the furnishing of this document does not give you any license to these patents, trademarks, copyrights, or other intellectual property.  2000 Microsoft Corporation. All rights reserved. Microsoft, Active Directory, ActiveX, BackOffice, BizTalk, FrontPage, Microsoft Press, MSDN, MS-DOS, PowerPoint, Visio, Visual Basic, Visual C++, Visual InterDev, Visual J++, Visual Studio, Win32, Windows, and Windows NT are either registered trademarks or trademarks of Microsoft Corporation in the U.S.A. and/or other countries. Other product and company names mentioned herein may be the trademarks of their respective owners. Program Managers: Rhy Mednick, Susie Parrent Instructional Designer: Susie Parrent Subject Matter Experts: David Chesnut, Sam Gill (TechnoWiz), Michel Pahud Media Management: David Mahlmann Editing Manager: Lynette Skinner Editor: Mick Alberts, Jennifer Linn Production Manager: Miracle Davis Print Coordinators: Linda Lu Cannon (Write Stuff), Marlene Lambert (Online Training Solutions, Inc.) Build Coordinator: Eric Wagoner Graphic Artist: Scott Serna Test Lead: Eric Myers Manufacturing Manager: John Williams Group Product Manager: Juan Fernando Rivera Lead Product Manager, System Services and Infrastructure: Edward Dudenhoefer Manufacturing Manager: Rick Terek Operations Coordinator: John Williams Manufacturing Support: Laura King; Kathy Hershey Lead Product Manager, Release Management: Bo Galford Group Manager, Courseware Infrastructure: David Bramble General Manager: Robert Stewart Module 7: Business Logic for Disconnected Components iii Instructor Notes Presentation: 90 Minutes Lab: 60 Minutes In the preceding module, “Business Logic for Connected Components,” you introduced students to cooperative processing among synchronous business objects in an enterprise solution. This module provides students with an introduction to cooperative processing among business components that are disconnected in time and space. After completing this module, students will be able to: !✂Describe the design and implementation of disconnected business logic and how to apply design patterns to the design of business logic. !✂Describe the technologies used in implementing disconnected business logic: COM+ queued components and loosely coupled events (LCE). !✂Create a physical design for a queued component. !✂Create a physical design for event notification. Materials and Preparation This section provides the materials and preparation tasks that you need to teach this module. Required Materials To teach this module, you need the following materials: !✂Microsoftfi PowerPointfi file 1910A_07.ppt !✂Module 7: Business Logic for Disconnected Components !✂Lab 7: Business Logic for Disconnected Components Preparation Tasks To prepare for this module, you should: !✂Read all of the materials for this module. !✂Complete the lab. iv Module 7: Business Logic for Disconnected Components Demonstration This section provides demonstration procedures that will not fit in the margin notes or are not appropriate for the student notes. Queued ComponentsTo prepare for the demonstration • Review the instructions in the student notes. COM+ Events ! To prepare for the demonstration • Review the instructions in the student notes. Module 7: Business Logic for Disconnected Components v Module Strategy Use the following strategy to present this module: !✂Introduction to Disconnected Business Logic The purpose of this section is to introduce students to the disconnected business logic layer. The business needs of an application require its interaction with other business applications. Frequently, these interactions can be separated in time and space. Two business scenarios can summarize the business requirements for loosely coupled mechanisms: • Response is never required The client’s job is complete when the call has been made and the message or notification is sent. This model works well for applications whose only task is input. • Immediate response not required In this scenario, the application does not require an immediate response but expects some form of acknowledgement at some time in the future. In the topic “The Business Problem,” illustrate disconnected business logic by using SneakerNet as an example. Point out that when using SneakerNet you can pass files but you don’t guarantee delivery. Contrast this with using Message Queuing, where delivery is guaranteed. In the topic “Business Requirements,” illustrate the interaction with the following example. If you are planning a trip from San Francisco to Tel Aviv, you can book your flight with Vigor Airlines (VA) and Blue Sky Airlines (BA). VA would be your carrier from San Francisco to London, and BA would be your carrier from London to Tel Aviv. VA acts as your primary agent and can confirm your reservation on its flights but cannot confirm your reservations on BA. VA can send a message to BA to ask for confirmation. The BA system will subsequently confirm or deny your reservation and notify VA accordingly. !✂TechnologiesThe purpose of this section is to introduce students to Message Queuing, queued components, and COM+ events. Spend time demonstrating queued components and COM+ events and answering student questions about these two demonstrations. In the topic “Message Queuing,” continue using the VA/BA example to explain the operation of message queuing. !✂Logical Design of Disconnected Business LogicThe purpose of this section is to introduce students to the two design patterns that can be used in the logical design of disconnected business logic: Observer and Queue. In the topic “Queued Components and Transactions,” explain the concept of a transaction in a disconnected logic environment and the need for a compensating transaction. You can use the example of VA and BA to explain that if BA returns a denial of a reservation you would need to add to the application a compensating transaction. The compensating transaction would reverse the confirmation of a VA flight since it is no longer applicable if the connection from London to Tel Aviv cannot be made. ... - tailieumienphi.vn