A Web application may expand into a large-scale application consisting of many HTML documents and related programs. In many cases, however, such a Web application can be considered a collection HTML documents and simple programs as shown below:
Therefore, the following tasks must be taken to develop a Web application:
Creating a request page (Web page for invoking the application)
Creating the relationship between the request page and the associated COBOL program
Creating application control logic (e.g., session management)
Creating business logic
Creating a result page (Web page for processing resulting output)
Creating the relationship between the result page and its associated COBOL program
To reduce the workload posed by tasks 2, 3, and 6 above, the following three functions are supplied as assist functions for Web application development in the COBOL Project Manager:
The Web application wizard generates Web application projects and program templates (corresponding to [1], [2], and [4] in the figure above).
When necessary, the wizard also creates a Template of the related request pages and result pages.
This tool generates a program that retrieves Web parameters from an input form in a request page. (The program indicated by [2] in the figure above will be generated.)
This tool generates a program that replaces variable names contained in the model of a result page and outputs a result page (indicated by [4] in the figure above).
The three assist functions above operate as part of the COBOL Project Manager, and enable operations equivalent to those of conventional COBOL development environments for developing and testing applications, and managing resources.
Note
HTML documents can also be included as part of the program resources in a project. This enables the COBOL Project Manager to reference and edit HTML documents, but it does not check the dependencies between HTML documents and generated programs.
See Figure "Overview of assist functions for Web application development."
Figure 1.1 Overview of assist functions for Web application development
Applications with the following interfaces can be developed using the assist functions for Web application development:
Most Web servers support CGI as the standard interface. CGI programs must be created in .EXE executable format (not as .DLL files). To create a CGI Web application in COBOL, use COBOL CGI subroutines. Refer to the COBOL CGI Subroutines User's Guide for details.
ISAPI, which is supported by Microsoft® Internet Information Server (IIS). ISAPI applications must be created in .DLL executable format (not as .EXE files). To create an ISAPI Web application in COBOL, use the COBOL ISAPI subroutines. Refer to the COBOL ISAPI Subroutines User's Guide for details.
