Planning the Host Integrator Project
A model is the representation of a host application's connections, screens, navigation, and data flow that you build with the Verastream Host Integrator Design Tool. Once you have modeled your host application, you deploy the resulting model to a Host Integrator Server, where it can provide real-time access to host data through web-enabled services.
Building a good model of a host application requires a basic understanding of the business problem that will be solved using the Host Integrator model and associated components. Use the guidelines below to prepare for Verastream host application modeling.
Gather the basic information about the host and the host application.
Know the host operating system and any relevant details about the host application software. The more you know about your host application, the greater the likelihood that you'll have an effective, robust model.
Determine the data you want to access in the host application.
If you're not familiar with the host application yourself, a host application programmer or an experienced business user needs to identify logon procedures and the sequence of screens typically used to reach the data you want to access. As you build the host application model, each host screen used in the model is represented as an entity. An efficient host application model contains only as many entities as are required to perform the necessary transactions between the external application and the host application.
Take the time to create an easy-to-follow data map to simplify the process of building the model. This exercise may reveal multiple screens and operations that display the same data. Whenever possible, model the screen that shows the data in its updated form for the transaction in question.
Identify the environment where the host data should be available.
Will the host data be presented on a web page for customers or users? Is the host data to be used by another application? Know the requirements and the environment where the host data will be used. If you are only planning to update the host application with a more modern web page look and feel, you can build a simple model. However, if you plan to alter the work flow or interoperate directly with other applications, your model will need to be more complex.
What is the Web presentation technology? Know the requirements and the environment where the host data will be used. If you're not integrating the data with other applications, a simple rejuvenation of the host application may be sufficient. Otherwise, you should plan on setting up tables and procedures so that an external application, such as a Web service, has access to the host data. This decision has a direct impact on how your build your model.
Know the development requirements for the external application.
Host Integrator provides APIs for integrating host data through SQL, ASP, ASP.NET, JSP, Web Services, COM, and .NET. For a quick implementation, many of these options can be generated using Host Integrator's Web Builder.
You can use Host Integrator with Microsoft's Active Server Pages (ASP), ASP.NET, or a Java Server Pages (JSP) environment. In this environment, you can use Host Integrator to give users access to host data from a Web browser.
You can use Host Integrator to make host data available to another client/server application, whether or not it is Web-based.
Host Integrator support for object frameworks on application servers include Web Services, the Component Object Model (COM), and .NET. Application server deployments are especially well-suited for situations in which high volume host systems are extended to the Web. Additional business logic can be developed to add more functionality and capabilities to the system without any work or development required in the host system environment.
Plan for error handling.
Error handling is a very important part of the model-planning process. Learn where and how the model can fail or put the host application in an error condition. Then, build exception handling into your model for these cases to reduce the chance that your model will fail after it is deployed.
Review the modeling tips in the online help.
The modeling tips cover basic model style guide recommendations, a comparison of table-based vs. non-table-based models, basics on screen recognition and pattern usage, and host synchronization.