Microsoft Dynamics AX 2009 : Application Development and Runtime Configurations & Architecture of Dynamics AX

Application Development and Runtime Configurations

The Dynamics AX development and runtime environments support three logical configurations, as illustrated in Figure 1:

• Rich client application

• Web client application

• Integration client application

Rich Client Application

The rich client is the primary client for Dynamics AX. It is a regular Windows application with a user interface consisting of menus, toolbars, forms, and so on.

You can develop a rich client application configuration using only the MorphX development environment. The rich client application is hosted by the Dynamics AX runtime environment. Rich clients communicate with the Application Object Server (AOS) using the Microsoft remote procedure call (RPC) communication technology.

Web Client Application

The Web client is a client for Dynamics AX that runs inside a Web browser. It supports many of the same capabilities as the rich client does.

You develop a Web client application configuration by using the MorphX development environment, Microsoft Visual Studio 2008, and the Windows SharePoint Services framework. A Web client application is hosted by the Dynamics AX runtime, the ASP.NET runtime, and the Windows SharePoint Services runtime environments. SharePoint and ASP.NET components communicate via the Dynamics AX .NET Business Connector.

Integration Client Application

An integration client application brings Dynamics AX functionality into external applications, such as Microsoft Office Excel and Microsoft Office Outlook. An integration client application configuration is mostly developed using Visual Studio or other tools with .NET support or Windows Communication Foundation (WCF) support. Integration client applications are hosted by the Microsoft Dynamics AX runtime environment. ASP.NET Web services and IIS are required for hosting Web services. The external application communicates with the Dynamics AX runtime via the Dynamics AX Application Integration Framework (AIF) server or .NET Business Connector.

Architecture of Dynamics AX

As a developer of Dynamics AX applications, your primary focus should be on modeling application elements to meet business requirements, relying on the rest of the architecture to meet technical requirements. Before looking at application modeling, explained in the following section, take some time to review the stack diagram in Figure 2, which illustrates the key functional areas of the Dynamics AX architecture.

Figure 2. Architecture of Dynamics AX

The following sections explore key elements of this diagram and tell you where you can find more information about each.

Application Modeling

Application modeling is a method of declaratively specifying the structure and behavior of an application that is faster, less error-prone, and more precise than imperative programming. Specifying that data is mandatory for a field in a database record, for example, is fairly easy in the Dynamics AX application model because the Dynamics AX runtime environment ensures that the condition is true in all parts of the application that manipulate data in the table. This obsoletes the programming effort that would otherwise be required to maintain data integrity throughout the application.

The Dynamics AX application model also supports defining workflows. The defined workflows describe states and available actions for types of business documents. For example, a developer could model a Purchase Order Approval workflow that maps the tasks required to approve a purchase order. The workflows are honored by the Dynamics AX runtime environment, and the Windows Workflow Foundation engine is used for processing and configuring the workflows.

Logic Elements and Data Elements

Because application modeling typically isn’t flexible enough to meet all business requirements, the Dynamics AX business logic is specified by the X++ programming language. X++ is an object-oriented language, much like C# and Java, that supports inheritance, encapsulation, and polymorphism. The language also includes syntax for writing database statements, much like those found in the SQL database manipulation language.

The following X++ code snippet uses the X++ SQL syntax. The language combines the simplicity of data lookup from SQL with the expressive power of object-oriented programming. You can invoke a method call directly on an object retrieved from the database.

while select customer
    where customer.zipcode == campaignZipCode
{
    customer.sendEmail(campaignId);
}

The model elements and X++ source code that comprise an object’s definition are called application elements, and they are managed with the Application Object Tree (AOT) development tool. The AOT is a user control in the MorphX environment that manages a dictionary of application elements.

Application Frameworks

While developing your application, you can leverage a range of built-in application frameworks that provide typical technology requirements such as batching, number sequence generation, and error logging.

Runtime Environments

The Dynamics AX runtime environment and the Dynamics AX Enterprise Portal runtime environment execute the ERP application defined by the application model elements. The Dynamics AX runtime environment has model-driven features that are required for the support of user interaction with ERP database applications. For example, if you specify that a column model element on a user interface grid control requires mandatory data entry, the Dynamics AX runtime environment ensures that users enter data in that particular column.

The Dynamics AX runtime environment also has client and server features that are required to support the three-tier operations environment. For example, by automatically marshalling parameters, return values, and object references across the tiers, the Dynamics AX runtime environment ensures that all X++ business logic marked to run on the server tier will execute on the AOS. As a developer, you still need to pay attention to these aspects because they can impact performance.

Communications

Dynamics AX leverage many different standard communication protocols, including RPCs, HTTP, and SOAP, to invoke Web services.

As an application developer in Dynamics AX, you don’t have to understand the implementation details of these protocols, but you must pay close attention to the performance aspects when invoking logic on remote tiers. You need to keep in mind network properties such as bandwidth and latency to ensure the resulting application is responsive.

Model Layering

A cardinal requirement of an ERP system is that it be able to meet the customer’s needs. If you’re in the business of building general solutions that many customers license and install, you need a way for individual customers to customize your solution.

The application model layering system supports fine-grained partner and customer customizations and extensions. The MorphX development environment manages the application elements that exist in multiple layers of the model, and the runtime environment assembles the application elements from different layers so that application object instances can be created with customized and extended structure and behavior.

Licensing, Configuration, and Security

Any ERP application has technical requirements for licensing, configuration, and security. In Dynamics AX, the developer can control the behavior of these aspects directly in the application model. Licensing, configuration, and role-based security are enforced at run time—for example, the only enabled user interface components the user sees are those that he or she has access to.

User and external application interactions are authenticated by the Windows integrated security system before any application features can be accessed. After authentication, the Active Directory service is used to associate a Windows user with a Dynamics AX user. Dynamics AX provides a security framework for authorizing Dynamics AX user and user group access to menu items and database data.

Database Layer

The Dynamics AX database layer supports both SQL Server and Oracle database systems. The database layer enables developers to focus on modeling the tables and fields required for various business scenarios without being concerned about SQL Server or Oracle specifics. For example, you can use the same X++ logic to query data regardless of which physical database engine the data is persisted in.

The Windows XP, Windows Vista, and Windows Server operating systems provide the technology that components use to communicate with the Dynamics AX runtime environment.