Professional MTS and MSMQ with VB and ASP [Anglais] [Relié]

Who is this book for? This book is designed for developers who are now building, or just starting to build, high performance and reliable web-based applications for a whole range of uses. It will also benefit those who want to learn more about the design and structure principles behind DNA as a whole. It assumes working knowledge of basic web site construction techniques, HTML, Active Server Pages, and some familiarity with Visual Basic. What does this book touer? • How DNA helps you build secure and robust distributed applications • Detailed look at the requirements of DNA and the services it uses • The principles of component design and implementation for use in transacted applications • An introduction to MTS and MSMQ and their administration • Programming details for the ActiveX interfaces in MTS and MSMQ • A review of application security, including IIS and SQL Server • Full details of the MTS and MSMQ security models and their use • A detailed real world case study, running through the book • Pointers to using the technologies in your own applications

Now that we've examined the core concepts of DNA and seen the kinds of components that we can use within its architecture, we can move on to look at where Microsoft Transaction Server (MTS) comes into the picture. Unfortunately, Microsoft momentarily lost their legendary knack of giving their products really useful and meaningful names when they christened this little baby. Yes, MTS does have something to do with 'transactions', but in fact it does a lot more useful things as well.

In this chapter we'll start off by looking at what MTS is, and why it's suddenly become one of the hottest new technologies around at the moment. We'll also discuss what transactions are, and you'll see why the name Transaction Server is a misnomer for this exciting new technology.

Then, once we've got to grips with the theory of MTS, we'll move on to look at how we use it in our applications. We'll show you just how easy it is to take advantage of its services with existing components, and we'll also be adding MTS integration to the simple WCCFinance component we developed in the previous chapter.

So, in this chapter, you'll see:

What Microsoft Transaction Server is, and what it can do.

What transactions are, and how MTS makes them more powerful and easier to use.

What levels of transaction support are available now, and will be in the future.

How we build new components and adapt existing ones for use with MTS. How we install components into MTS, and use them in applications.

To start with, let's look at the background and basic principles of MTS.

What is Transaction Server?

MTS is an integral part of Windows NT, and is installed by default as part of the operating system in NT5. It is a service in much the same way as Internet Information Server or the File and Print services that we now take for granted. In other words, it is part of the system that is available in the background whenever one of our applications requires it.

Control and configuration of MTS is via either a snap-in to the Microsoft Management Console, or through the HTML administration pages that are included with MTS. This is very similar to the interface provided for Internet Information Server 4, and gives an integrated management function that is useful when building and setting up distributed applications.

At the time of writing, MTS was available as an add-on to Windows NT4 in the form of the NT4 Option Pack, or as part of the Windows NT4 Enterprise Edition. The Option Pack can be installed over the top of Windows NT4, requiring Service Pack 3 and Internet Explorer 4.01. Both are included in the Option Pack and are installed automatically.

What Does Transaction Server Do?

To understand what MTS is and what it does, we need to first make one very important point clear. This software should really have been named Microsoft Component Server, not Microsoft Transaction Server. MTS is all about managing the way applications use components, and not just about managing transactions. Yes, transactions are a big part of many applications we write and MTS can help to manage these-but MTS also provides a very useful service for applications that don't use transactions at all.

We're already tossing about words like 'transactions'-which are short on real meaning at the moment. To be able to define MTS accurately, we first need to understand what goes on inside it in the most basic way. That's what we'll do in this section, and you won't see anything more about transactions until later in the chapter.

We'll start by looking at the way we traditionally use components within our applications. This will help you to understand how and why MTS can make the whole process more efficient.