INFO 324
Team Process and Product
Week 2
Dr. Jennifer Booker
College of Information Science and
Technology
Drexel University
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Introduction
Agenda
• SRS discussion – OPOW1
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OPOW – Original Request
Your client has emailed this request:
“I am working on a digital library project. See ensemble.org. As part
of this project, we want to make collections of course materials visible
on the Ensemble portal. To do that we need to harvest metadata
describing each course material in a collection. To do that we are
using OAI-PMH, a protocol for harvesting metadata. See
http://www.openarchives.org/.
We need a program that can reformat a file of metadata to match the
OAI-PMH protocol. The input would be a text file with metadata
extracted from one or more repositories of course materials.
Can you help?”
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OPOW SRS
• Activity: class discussion based on homework
assignment OPOW1
• Goals
– Practice critiquing an SRS
– Discussion of SRS strong and weak points
• Discussion starting points
– What questions would you ask about the SRS?
– What design decisions are being made?
• Should they be deferred to the design?
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Agenda
• SDS and SDS-V1 template
• Activity: Design entities
• Assignment: OPOW2 – SDS
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Software Design Specification
• SRS: WHAT should the system do
• SDS: HOW should the system do it
• Switch to designing in the SDS
– Don’t repeat requirement statements
– But do refer to them explicitly
• Get into the particulars of design entities
• Key question: if you sent the SDS to a
development group would they build the
system the clients wants?
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SDS-V1 Template Tour
• 1 Introduction
– 1.1
– 1.2
Scope
Definitions, Acronyms, and Abbreviations
• 2 Architectural Description
• 3 Interface Description
– 3.1
– 3.2
– 3.3
User Interface
Data Interface
Programming Interface
• 4 Detailed Design
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Design Entity Content
• Entity ID and Name
• Type – Be specific and consistent
• Requirement – Always and only a pointer to a
particular requirement in the SRS
• Description – varies by entity type
– Key question: Would someone else know how to
build this entity based on the description?
– Level of detail varies by project size and
designer-implementer relationship
• Need to always cover the basics rather than assume
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Detailed Design Entities
• What are the common types?
• What should you specify for each type?
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Sample Entity Types
• Database (overview)
– Database table
• User interface (overview)
– Screen, Web page
• Function (program code)
• File
• …. And so on
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Description for a Table Entity
• Name
• Key(s)
• Name and type of each data element
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Example: Table
4.14 Active Listings
Type: Database table
Requirement: Partially fulfills requirement 3.2.9
Description:
Name: Active_Listing
This table contains a row for each item available for trading. Table content
is defined in Figure 6.
Attribute
UserID
Key
PK
DatePosted
ItemID
FK
Type
Length
STRING
15
STRING
8
STRING
10
TradeValue
BOOLEAN
TradeDescription
STRING
1
300
Figure 6 – Active Listings database table
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Function
•
•
•
•
Name
Parameters
Return type and meaning
Algorithm or description of processing
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Example: Function
4.3 Trim Trailing Characters
Type: Function
Requirement: Fulfills requirement 3.2.6
Description
Name: trimright
Parameters: target – a pointer to a string to be trimmed
guide – a pointer to a set of the characters to trim from target
Return: An integer representing the length of target after trimming
Use: int trimright(char *target, char *guide)
Processing: Scan target from right to left and truncate characters until
encountering a character in target that is not in guide. Calculate the new
length of target and return that value.
Example:
target = “ab/cd///”
guide = “/”
trimright( *target, *guide) returns 5 and leaves target = “ab/cd”
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Screen
• Name
• Layout - at least a rough drawing
• Definition of data that appears on the
screen
– Tie to internal data element names
• Interaction description
– Behavior when a user interacts with the
screen
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Example: Screen
18 – Main Menu
Type: Screen
Requirement: Partially fulfills requirement 25.
Description: This is the first screen that the Hero will see upon
opening PokerAid and it provides access to each of the PokerAid
features.
The screen will contain a column of buttons with a brief description of
each. The screen will be overlaid on the PokerAid standard screen
template.
Start/Stop
Toggle to begin or end processing of poker data
Configure
Access configuration options
Exit
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Exit PokerAid
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Activity: Design Entities
• List design entities for Sandy’s Castle
– Name and type
• Create a full design for several of these
entities
– For interface entities, include: system name,
screen name, user instructions, navigation
options (not just ok/continue but also cancel,
exit, maybe reset or main menu nav options)
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Assignment: OPOW2
• Review a partial OPOW SDS
– Note questions for the designer - What
questions would you need to ask the designer
to be able to implement OPOW from this
SDS?
– Are all entities clear and complete?
• Define entities for the user interface
• Define entities for an alternative user
interface design
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In Your Future...
• Next Class
– Design discussion – based on OPOW2
– New mini-project
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