Requirements Engineering for Web Applications

SR: System Vision Document Written by key stakeholders Written by key stakeholders An executive summary of the solution An executive summary of the solution A high-level description of the problem that the system will address as a set of issues stated in business terms. A high-level description of the problem that the system will address as a set of issues stated in business terms. The list of stakeholders and users of the system with their descriptions, concerns, and responsibilities. The list of stakeholders and users of the system with their descriptions, concerns, and responsibilities. A list of features of the system expressed in business terms. A list of features of the system expressed in business terms. A list of system constraints described in business terms. A list of system constraints described in business terms. A list of nonfunctional constraints related to overall enterprise environment, including development standards and processes of the organization, limitation in cost or resources, etc. A list of nonfunctional constraints related to overall enterprise environment, including development standards and processes of the organization, limitation in cost or resources, etc.

SR: User-Stories An effective intermediate step to the use cases An effective intermediate step to the use cases A half-day workshop with representative of the user community A half-day workshop with representative of the user community Ask them to write up what they expect the possible interactions of the various users with the system are as stories Ask them to write up what they expect the possible interactions of the various users with the system are as stories Not give the users too much time to write stories. Not give the users too much time to write stories. User stories are a throwaway artifact, not maintained. User stories are a throwaway artifact, not maintained. Used as a basis for system use cases Used as a basis for system use cases Good for user experience model Good for user experience model

User story example

SR: Use Case Model - 1 Actors Actors A role played by a person or system that is external to the system but interacts with it. A role played by a person or system that is external to the system but interacts with it. System use case System use case A sequence of actions that describe the interaction between the actors and the system for a specific task or function A sequence of actions that describe the interaction between the actors and the system for a specific task or function Use case model Use case model UML diagrams and the use case definitions UML diagrams and the use case definitions A synthetic view of the functionality of the system A synthetic view of the functionality of the system

Use case template

SR: Use Case Model - 2 Objectives of the use case model Objectives of the use case model Produce diagrams that represent the actors and their relationships (actor diagrams) Produce diagrams that represent the actors and their relationships (actor diagrams) Produce diagrams that represent the use cases with the actors and their relationships (use case diagrams) Produce diagrams that represent the use cases with the actors and their relationships (use case diagrams) Organize the use cases into packages that map to the conceptual categorization of the system functions Organize the use cases into packages that map to the conceptual categorization of the system functions

Initial UML diagram of actors

Actor Model

SR: Use Case Model - 3 Use the following to produce first draft of use cases Use the following to produce first draft of use cases User stories User stories Business use case model Business use case model Business object model Business object model Vision document Vision document Organize use cases into “business packages”, each of which contributes to the realization of a specific business function Organize use cases into “business packages”, each of which contributes to the realization of a specific business function

Use case model: Acct Mngmnt

Use case Model: Store Front

Use case model: Maintenance

Use case model: Organization

Use case model: mind map Use Cases User Acct Mngt Store front Maintenance Create Account Manage Users Manage Account Sign in Sign out Checkout Review shopping cart Browse Catalog

Use case model: system boundary Create Account Manage Users Manage Account Sign in Sign out Checkout Review shopping cart Browse Catalog Anonymous User Registered Buyer Admin Credit Card System

Use case: sequence diagram

SR: Use Case Model - 4 Refine use cases Refine use cases Use a template for use case definition Use a template for use case definition Remove any ambiguity Remove any ambiguity Resolve conflicts Resolve conflicts Use the business rules to identify alternative paths in the use cases Use the business rules to identify alternative paths in the use cases Add concepts that are pertaining to the system, but the business to the business/system glossary Add concepts that are pertaining to the system, but the business to the business/system glossary

SR: Test cases As soon as the use cases are defined, test designer should start identifying As soon as the use cases are defined, test designer should start identifying Test scenarios Test scenarios Test cases Test cases Preparing of test cases can also help in validating use cases Preparing of test cases can also help in validating use cases

SR: Summary Artifacts of SR Artifacts of SR Vision document Vision document User stories User stories Use case definition Use case definition Use case model Use case model System glossary System glossary Use case packages Use case packages