Active Server Pages and Lotus Domino
Active Server Pages and related services from Microsoft represent a big step forward compared to the first generation tools (CGI, PERL, etc.) previously used for integrating database tables and other systems into Web pages. As a dynamic content engine, Microsoft's ASP engine is sometimes compared to Lotus' Domino Server. ASPs provide the ability to create many different types of applications assuming that the time and development resources are available to program and maintain everything but the most rudimentary of operations. Also, these applications are inextricably tied to the Windows NT server. By comparison, the Domino cross-platform application development metaphor is "code-by-exception" rather than Microsoft's "code-by-default." Domino combines several high level application constructs - subforms, forms, views, agents - with flexible logic creation. Logic can be created with high level methods such as a point & click dialogue interface to simple commands, or the easy to learn Notes formula language. More sophisticated applications can take advantage of scripting languages, Java, JavaBeans, or ActiveX components when the higher level constructs and logic capabilities are not suitable. This enables applications to be quickly assembled and modified, allowing Domino application developers to focus on the business problem at hand rather than on low level coding.- Server Side Scripting. The server side script engine in IIS is the most fundamental piece of ASP technology. However, it requires script to be developed for all logic and can only be initiated when a page is called. Domino a provides more flexible server-side script capability with its Agent Manager technology. Logic creation is code-by-exception: Logic can be created using a point & click dialogue interface, the Notes formula language, Java or Basic-compatible LotusScript. Also, not only can agents can be triggered when a page is requested, but also when saved, or at pre-determined times on a scheduled basis.
- Dynamic/Personalized Content. The ability to execute logic and create HTML based on the results of a script give ASP the ability to provide dynamic and personalized content. Dynamic content creation and personalization are a default attribute of Domino: Every design element is programmable, user identity is maintained inherently, and Domino generates all pages at the time of request. Developers do not need to manually maintain user state, nor write complicated scripts and HTML to generate dynamic, personalized content.
- Database Driven Pages. Through the Active Data Object (ADO), ASP scripts can access back end systems to incorporate data in a Web page. Domino provides access to ODBC data sources in exactly the same manner through its LotusScript Data Object (LS:DO). Additionally, with Lotus' Domino.Connect, developers can natively access, in real time, a number of different data sources, including ODBC, Oracle, Sybase & DB2. Often without needing to write any script or code.
- Separate Content from Business Logic. Microsoft encourages developers to encapsulate much of an application's logic in custom-built Active Server Components to separate hard core application logic from the Active Server Page itself. However, even though an Active Server Component may encapsulate certain application logic, the script required to access and manipulate these components according to the 'business rules' of an application, still reside in the ASP page embedded within the HTML. With this page-based approach, a change to the layout, or to logic controlling a component, would need to be made to any file affected by the change. Changes would then need to be manually distributed (either by making the change again or through FILE-COPY) to any other servers housing that application. Domino's forms-based approach to applications, and its extensive use of design templates, truly allows the content of an application to be separate from its design and logic. Forms are used to control the layout of pages, and store logic behind elements within the form (e.g. fields). This allows the layout and logic of a page to be maintained independently of the information associated or created with the page. Templates store all the application design elements (forms, views, agents, etc.). For maintenance, modifications can be applied to the application's template, and Domino's replication technology will then automatically distribute those changes to all servers that house the application. The updates are automatically applied during a scheduled design update process.
- Open: No Proprietary Scripting Language. ASP technology provides native support for Microsoft's VBScript and JScript. JScript is Microsoft's implementation of the ECMA-262 language specification: JavaScript compatible. The script engine can also be extended by third party plug-in modules to support other scripting languages, REXX or PERL for example. Domino also provides an open scripting environment: In addition to LotusScript, Java can be used to create server-side script logic with Domino agents. Domino's code-by exception development metaphor provides a more flexible environment than supporting multiple script languages: In addition to sophisticated script development with Java, JavaBeans or ActiveX, Domino provides logic creation to those without professional development skills. Domino combines its sophisticated application development capabilities with high level application constructs (e.g. forms, views, fields etc.) and creation methods such as a point & click dialogue interface to simple commands or the easy to learn Notes formula language.
- Open: Browser Independent. Logic can be incorporated into ASP scripts to detect the type and version of the browser requesting a page. With this information, the application developer can present HTML based upon the type or version of the browser. By default, Domino presents browser independent HTML without programmer intervention. It can then be augmented programmatically in exactly the same manner as ASP applications: Information is accessed through CGI variables and logic can be incorporated to render a page in a certain manner based upon that information.
- Approachable. Microsoft considers developing Web applications with ASP technology "approachable" compared to how Web site builders have traditionally created interactivity. Customized pages and dynamically-generated HTML can be created more easily with ASP technology and VBScript than using traditional Web tools, such as C or PERL, to write CGI programs. Through its code-by-exception approach to developing applications, its high level programming constructs, its forms-based rather than page-based design metaphor, its logic creation for non-programmers - in addition to sophisticated development capabilities, - its use of templates for managing application design, its replication technology for application distribution, Domino goes far beyond what ASP technology offers in the way of approachability.
- No Manual Compiling. In contrast to traditional CGI programs needed for interactivity on Web sites, ASP scripts do not need to be manually compiled by the developer. Domino applications do not require manual compilation either.
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