A FRAMEWORK FOR WEBE

29.3 A FRAMEWORK FOR WEBE

As WebApps evolve from static, content-directed information sources to dynamic, user-directed application environments, the need to apply solid management and engineering principles grows in importance. To accomplish this, it is necessary to develop a WebE framework that encompasses an effective process model, populated

by framework activities 4 and engineering tasks. A process model for WebE is sug- gested in Figure 29.2.

Planning

Analysis

Architectural design

Formulation

Content design

Navigation

Engineering

design Production

Customer evaluation

Page generation

F I G U R E 29.2 The WebE process model

4 Recalling the discussion of process models in Chapter 2, framework activities are performed for all WebApps, while engineering tasks are adapted to the size and complexity of the WebApp to be developed.

The WebE process begins with a formulation—an activity that identifies the goals and objectives of the WebApp and establishes the scope for the first increment. Plan- ning estimates overall project cost, evaluates risks associated with the development effort, and defines a finely granulated development schedule for the initial WebApp increment, with a more coarsely granulated schedule for subsequent increments. Analysis establishes technical requirements for the WebApp and identifies the con- tent items that will be incorporated. Requirements for graphic design (aesthetics) are also defined.

The engineering activity incorporates two parallel tasks illustrated on the right side of Figure 29.2. Content design and production are tasks performed by nontechnical

WebRef

members of the WebE team. The intent of these tasks is to design, produce, and/or W3C, an industry

acquire all text, graphics, audio, and video content that are to become integrated into consortium that provides

the WebApp. At the same time, a set of technical design tasks (Section 29.5) are con- access to WWW

information of interest to ducted.

Web engineers can be Page generation is a construction activity that makes heavy use of automated tools accessed at

for WebApp creation. The content defined in the engineering activity is merged with

www.w3.org

the architectural, navigation, and interface designs to produce executable Web pages in HTML, XML, and other process-oriented languages (e.g., Java). Integration with component middleware (i.e., CORBA, DCOM, or JavaBeans) is also accomplished dur- ing this activity. Testing exercises WebApp navigation; attempts to uncover errors in applets, scripts, and forms; and helps ensure that the WebApp will operate correctly in different environments (e.g., with different browsers).

Each increment produced as part of the WebE process is reviewed during customer evaluation. This is the point at which changes are requested (scope extensions occur). These changes are integrated into the next path through the incremental process flow.

29.4 F O R M U L AT I N G / A N A LY Z I N G W E B - B A S E D S Y S T E M S

Formulation and analysis of Web-based systems and applications represent a sequence of Web engineering activities that begins with the identification of the overall goals for a WebApp and terminates with the development of an analysis model or require- ments specification for the system. Formulation allows the customer and the devel- oper to establish a common set of goals and objectives for the construction of the WebApp. It also identifies the scope of the development effort and provides a means for determining a successful outcome. Analysis is a technical activity that identifies the data, functional, and behavioral requirements for the WebApp.