PROJECT: Club Connect

1. Overview

Club Connect is an application targeted at club members who are students at the National University of Singapore (NUS). It aims to make the tedious process of club management easier and more effective.

Club Connect is an application that a user who loves to type would fancy - in other words, it uses a Command Line Interface (CLI). All output is displayed on a Graphical User Interface (GUI) - which is just computer jargon for a display that includes panes, menus and message boxes.

2. Purpose of Portfolio Page

This portfolio page describes the contribution I have made to Club Connect’s development – in terms of code, tests, and documentation. It comprises of extracts from the User Guide and Developer Guide, highlighting major and minor features that I worked on during the course of the semester. It also describes some of the other contributions I made – testing, PR reviews, and product management.

3. Summary of Contributions

Major enhancement: Task-Management
What it does: allows users to add, assign, delete and modify tasks.
Justification : Members of a club have certain responsibilities and must carry out tasks to fulfil their responsibilities. Furthermore, EXCO members can delegate tasks to other members which they must perform within a stipulated time period. Maintaining a record of tasks is crucial as it help maintain transparency and accountability of the club.

Minor enhancements:

  • Added a Group attribute to Member as well as a command to remove a Group from the application.

  • Added an auto-complete feature which can be used by pressing the TAB key.

  • Added email functionality.

Code Contributed : [Functional code] [Test code]

Other contributions:

  • Project Management

    • Managed all releases on GitHub and Milestones.

    • Assumed responsibility of the Team Leader where I took important decisions regarding the product development.

  • Documentation

    • Added and improved sections of the User Guide and Developer Guide.

  • Features and enhancements

    • Added aliases to existing and new commands - Pull request #159.

    • Added Group attribute to Member : Pull Request #66.

    • Added deletetask, viewalltasks, and viewmytasks functionality - pull requests #125, #142, and #147.

  • Community

    • PRs reviewed (with non-trivial review comments): #53, #67, and #155.

    • Reported bugs and suggestions for other teams during Peer Testing.

4. Contributions to the User Guide

Given below are sections I contributed to the User Guide. They showcase my ability to write documentation targeting end-users.

4.1 Major Enhancement: Task-Management

Start of Extract (from User Guide)

Adding a task: addtask (Since v1.3)

Adds a task to Club Connect.
Format: addtask desc/DESCRIPTION d/DUE_DATE ti/TIME
Aliases: addt, task

  • The date and time attributes must be valid dates and time (in 24-hour format).

  • The range of the year in the Date is 1900 - 2099.

  • By default, the Assignor and Assignee of the task is the member that is currently logged in.

  • If you wish to assign taks to other members in the capacity of an Exco member, use the assigntask command.

  • The default Status given to a newly created task is Yet to Begin. This can be updated using the changetaskstatus command.

Duplicate tasks are not allowed.

Examples:

  • addtask desc/Book PGP Function Room 3 d/02/06/2018 ti/19:00
    Adds a task with description Book PGP Function Room 3 due on 02/06/2018 at 19:00.

  • addtask desc/Buy Food d/03.06.2018 ti/15:00
    Adds a task with description Buy Food due on 03/06/2018 at 15:00.

Changing the status of your task : changetaskstatus (Since v1.5rc)

Changes the status of a task in Club Connect.
Format: changetaskstatus INDEX st/STATUS
Aliases: cts, changestatus, status

  • INDEX must be a positive integer 1, 2, 3, …​

  • The STATUS can be one of Yet To Begin, In Progress, and Completed.

  • You can only change the status of a task that you have been assigned or a task that you have assigned.

  • Club Connect detects if there is no change in the STATUS.

Tasks are color-coded by status:
Yet To Begin
In Progress
Completed

Examples:

  • changetaskstatus 1 st/In Progress
    Changes the status of the 1st task to In Progress in the task listing.

  • status 3 st/Completed
    Changes the status of the 3rd task to Completed in the task listing.

The three types of statuses are shown below in Figures 12, 13 and 14.

yettobegin
Figure 1. A task that is a member is yet to begin.
inprogress
Figure 2. A task in progress.
completed
Figure 3. A completed task.

End of Extract (from User Guide)

4.2 Minor Enhancement: Delete Group

Start of Extract (from User Guide)

Deleting a group : deletegroup (Since v1.1)

Deletes the specified group from Club Connect.
Format: deletegroup g/GROUP
Aliases: rmgroup, delgroup

  • Deletes the specified group from Club Connect.

  • Once the group is deleted, all members who were part of the group will be assigned to the default group member.

  • The group must not be a mandatory group (Member) as that is the default group.

  • The group Exco cannot be deleted.

  • The group must exist in Club Connect and be in valid format (i.e. no white-spaces and non-empty).

This command is for Exco members only.

Examples:

  • deletegroup g/logistics
    Deletes the logistics group from Club Connect.

  • deletegroup g/pr
    Deletes the pr group from Club Connect.

Figure 24 shows the output of the deletegroup command.

deletegroupoutput
Figure 4. Output of deletegroup command.

End of Extract (from User Guide)

5. Contributions to the Developer Guide

Given below are sections I contributed to the Developer Guide. They showcase my ability to write technical documentation and the technical depth of my contributions to the project.

5.1 Major Enhancement: Task-Management

Start of Extract (from Developer Guide)

Task-Management

Tasks are pieces of work to be done or undertaken. Members can create tasks for themselves, and can also be assigned to a task by Exco members.

Current Implementation

The task-management mechanism is facilitated by several command classes in Club Connect, which will be covered in subsequent sub-sections.

Task-management commands require a member to be logged in (and thus by extension, an initial sign-up).

Figure 31 below shows the UML diagram of the Task class.

TaskUML

Figure 31. Task UML Diagram

Adding Tasks

Adding Tasks is facilitated by the AddTaskCommand. When this command is invoked, it adds a task with the input Description, Date, and Time. The status of every newly created task is by default set to Yet To Begin. The Assignor and Assignee of the task is set to the Matric Number of the member who is currently logged into Club Connect.

Figure 32 below shows the UML representation of AddTaskCommand.

AddTaskCommandUML

Figure 32. UML diagram of AddTaskCommand.

Figure 33 shows the flow of parsing an AddTaskCommand object:

SDforAddTaskCommandParser

Figure 33. Sequence Diagram for AddTaskCommand parsing.

Figure 34 depicts the high-level sequence of events that take place.

SDforAddTask

Figure 34. Sequence Diagram for adding a task.

Design Considerations

Aspect: Displaying Assignor and Assignee

  • Alternative 1 (current choice): Displays currently logged-in member as Assignor and Assignee.

    • Pros: It is required for assigntask.

    • Cons: Displaying the same matriculation number twice is redundant.

  • Alternative 2: Don’t display Assignor and Assignee as it is a personal to-do list.

    • Pros: Takes care of redundancies in Alternative 1 above.

    • Cons: The implementation of assigntask becomes more complex.

Changing Task Status

Changing a task’s status is made possible by the ChangeTaskStatusCommand.

Figure 44 below shows the UML representation of ChangeTaskStatusCommand.

ChangeTaskStatusCommandUML

Figure 44. UML Diagram of ChangeTaskStatusCommand.

Parsing of the command is performed by ChangeTaskStatusCommandParser, which returns a ChangeTaskStatusCommand object.
Figure 45 below depicts the parsing of the ChangeTaskStatusObject.

SDforChangeTaskStatusCommandParser

Figure 45. Sequence Diagram for ChangeTaskStatusCommand parsing.

Figure 46 below describes the high-level sequence of events that take place.

SDforChangeTaskStatus

Figure 46. Sequence Diagram for changing the status of a task.

Design Considerations

Aspect: Who can change task status?

  • Alternative 1 (current choice): Assignor or Assignee can change the task status.

    • Pros: They are directly associated with the task.

    • Cons: Exco should also have a say.

  • Alternative 2: Exco, Assignee or Assignor can change status.

    • Pros: Exco’s powers kept in check.

    • Cons: Exco may misinterpret status of the task.

End of Extract (from Developer Guide)

5.2 Minor Enhancement: Delete Group Mechanism

Start of Extract (from Developer Guide)

Delete Group Mechanism

Current Implementation

The deletegroup mechanism is facilitated by the DeleteGroupCommand class. It allows Exco members to delete a group from Club Connect. The group of all members part of the group that is to be deleted will be changed to the default group - member.

The DeleteGroupCommand extends from UndoableCommand as it is an undoable command. Figure 58 below depicts the UML representation of the Command.

DeleteGroupCommandUML

Figure 58. UML Diagram of DeleteGroupCommand.

DeleteGroupCommandParser is responsible for parsing the deletegroup command. It returns a DeleteGroupCommand object after parsing the Group. The parsing of the command is shown below in Figure 59.

The method where the deletion takes place in each member is ClubBook#deleteGroupFromMember.

private void deleteGroupFromMember(Group toRemove, Member member)
        throws MemberNotFoundException {
    if (!member.getGroup().toString().equalsIgnoreCase(toRemove.toString())) {
        return;
    }
    Group defaultGroup = new Group(Group.DEFAULT_GROUP);
    Member newMember = new Member(member.getName(), member.getPhone(), member.getEmail(), member.getMatricNumber(),
            defaultGroup, member.getTags());
    try {
        updateMember(member, newMember);
    } catch (DuplicateMatricNumberException dme) {
        throw new AssertionError("Deleting a member's group only should not result in a duplicate. "
                + "See member#equals(Object).");
    }
}
SDforDeleteGroupCommandParser

Figure 59. Sequence Diagram for the parsing of DeleteGroupCommand.

The high-level sequence of events is depicted in Figure 60 below.

SDforDeleteGroup

Figure 60. Sequence Diagram for delete a group from Club Connect.

Design Considerations

Aspect: Implementation of DeleteGroupCommand

  • Alternative 1 (current choice): Overwrite the relevant Member objects with new Member objects.

    • Pros: Easy to implement.

    • Cons: Requires looping through all the members in Club Connect.

  • Alternative 2: To maintain a UniqueGroupList

    • Pros: Cleaner implementation.

    • Cons: Relatively difficult to implement.

End of Extract (from Developer Guide)

Appendix A : Proposed Enhancement

Data Encryption

External Behaviour

Implementing this feature will have no effect on the functionality that Club Connect provides to its users. The major change that this feature will bring is securing user data. Users can rest assured that none of their data can be leaked to malicious foreign parties.

Justification

Data privacy is a controversial topic in today’s world. When personal data falls into the wrong hands, it can be misused in ways we can’t possibly imagine. Every corporation, organization and service must provide data privacy not only because it’s the law, but also to maintain consumer satisfaction.

Implementation

Start of Extract (from Developer Guide)

[Proposed] Data Encryption

Rationale

Data encryption is key to any App that deals with personal data of individuals.

We plan to use Symmetric Key Encryption to ensure the confidentiality of data.

How Symmetric Key Encryption works

Symmetric key encryption is an encryption philosophy where the two communicating parties share a pre-established secret key k. It consists of 2 algorithms E (Encrypting or Encoding) and D (Decryption or Decoding) which take in the same key k to perform their respective operations.

The 2 algorithms E and D are efficient algorithms, such that:

  • D(E(k,m)) = m, where 'm' is the message that needs to be kept confidential.

  • For k chosen uniformly at random, E(k,m) gives no additional information about 'm' to an adversary.

Proposed Implementation

We plan to make use of classes that are defined in Javax’s Crypto package.

The classes that would feature in the implementation are:

  • KeyGenerator → constructs a secret (symmetric) key.

  • Cipher → provides the functionality of a cryptographic cipher for encryption and decryption.

The construction of a symmetric key is done by passing the algorithm the encryption will use. The Advanced Encryption Scheme (AES) algorithm is a secure encryption algorithm that has proven been proven secure. A 128-bit AES symmetric key will be used to encrypt all data files.

Once the key is generated, all data will be encrypted with AES. Anyone who wishes to view the decrypted form of the data must possess the secret key.

Figure 74 below describes the encryption procedure used in AES – specifically, the Cipher Block Chaining (CBC) mode.

encryption

Figure 74. AES – CBC mode encryption.

Figure 75 below shows the decryption process.

decryption

Figure 75. AES – CBC mode decrption.

End of Extract (from Developer Guide)

Appendix B: Other Enhancements and Features

1. Auto-Complete Command Mechanism

Start of Extract (from Developer Guide)

Auto-Complete Command Mechanism

Current Implementation

The auto-complete mechanism is an enhancement added to reduce the frequency pf typos and thus by extension, invalid commands.

It makes use of the key press event KeyEvent. Pressing TAB cycles through all possible commands based on user input.

The ArrayList<String> commandList in CommandList.java stores all the command formats.

Here is the implementation for handling the key-press event:

private void handleKeyPress(KeyEvent keyEvent) {
    switch (keyEvent.getCode()) {
    .
    .
    case TAB:
        keyEvent.consume();
        completeCommandIndex++;
        autoComplete(commandTextField.getText());
        break;
    .
    .
    }
}

Shown below is the implementation of the autoComplete method.

private void autoComplete(String input) {
    if (!input.equals("")) {
        if (oldInput == null) {
            oldInput = input;
        } else if (!input.startsWith(oldInput)) {
            oldInput = input;
            completeCommandIndex = 0;
        }
        List<String> completedCommands = LogicManager.COMMAND_LIST.stream().filter(s -> s.startsWith(oldInput))
                .collect(Collectors.toList());
        if (!completedCommands.isEmpty()) {
            replaceText(completedCommands.get(completeCommandIndex % completedCommands.size()));
        } else {
            replaceText("");
        }
    }
}

Design Considerations

Implementation of cycling through commands

  • Alternative 1 (current choice): Use string manipulation to store old input and only change it if the new input doesn’t start with the old input.

    • Pros: It’s easy to implement.

    • Cons: It’s not so good in terms of code quality.

  • Alternative 2: If there are 'N' commands that start with XXX, create 'N' strings with each concatenated one after the other in increasing length i.e. XXX1, XXX1XXX2, …​ ,XXX1XXX2XXX3…​XXXN. Keep truncating the commands not needed from the front.

    • Pros: Possibly cleaner code.

    • Cons: It’s relatively hard to implement.

End of Extract (from Developer Guide)

2. Assign Tasks

2.1 Contribution to User Guide

Start of Extract (from User Guide)

Assigning a task: assigntask (Since v1.4)

Adds a task to Club Connect and assigns it to a member.
Format: assigntask desc/DESCRIPTION d/DUE_DATE ti/TIME m/MATRIC_NUMBER
Alias: assignt

  • The date and time attributes must be valid dates and time (in 24-hour format).

  • The member who the task is meant to be assigned to must exist in the club book.

  • The default Status given to a newly created task is Yet to Begin. This can be updated using the changetaskstatus command.

Duplicate tasks are not allowed.
This command is for Exco members only.

This command assigns the task to the member based on the entered MATRIC_NUMBER.

Examples:

  • assigntask desc/Book PGP Function Room 3 d/02/06/2018 ti/19:00 m/A1234567H
    Assigns a task to A1234567H with description Book PGP Function Room 3 due on 02/06/2018 at 19:00.

  • assigntask desc/Buy Food d/03.06.2018 ti/15:00 m/A1122334K
    Assigns a task to A1122334K with description Buy Food due on 03/06/2018 at 15:00.

End of Extract (from User Guide)

2.2 Contribution to Developer Guide

Start of Extract (from User Guide)

Assigning Tasks

Assigning tasks can be accomplished with the AssignTaskCommand. Tasks are assigned to members through the Matric Number attribute.

Figure 35 below shows the UML representation of AssignTaskCommand.

AssignTaskCommandUML

Figure 35. UML diagram of AssignTaskCommand.

The implementation of assigning tasks is similar to that of adding tasks. The only difference is that the Assignor is set to the Matric Number of the member who is currently logged in.

The parsing of an AssignTaskCommand is performed by the AssignTaskCommandParser.
Figure 36 shows the flow of parsing an AssignTaskCommand object:

SDforAssignTaskCommandParser

Figure 36. Sequence Diagram for AssignTaskCommand parsing.

Figure 37 depicts the high-level sequence of events that take place.

SDforAssignTask

Figure 37. Sequence Diagram for assigning a task.

Design Considerations

Aspect: Displaying similar tasks for different Assignees

  • Alternative 1 (current choice): Make a copy of the task for every new Assignee if all other parameters are same.

    • Pros: Easy to implement

    • Cons: Clutters the TaskListPanel because of redundancies.

  • Alternative 2: Maintain a list of Assignee s in a task .

    • Pros: Reduces clutter in the TaskListPanel and is easy on the eye.

    • Cons: Relatively difficult to implement.

End of Extract (from User Guide)

3. Delete Tasks

3.1 Contribution to User Guide

Start of Extract (from User Guide)

Deleting a task : deletetask (Since v1.3)

Deletes the specified task from the club book.
Format: deletetask INDEX
Aliases: deltask, rmtask

  • Deletes the task at the specified INDEX.

  • The index refers to the index number shown in the most recent listing.

  • The index must be a positive integer 1, 2, 3, …​

Only Members who are the Assignor can delete their respective tasks.

Examples:

  • viewmytasks
    deletetask 2
    Deletes the 2nd task in the results of the viewmytasks command.

  • viewalltasks
    deletetask 1
    Deletes the 1st task in the results of the viewalltasks command.

End of Extract (from User Guide)

3.2 Contribution to Developer Guide

Start of Extract (from Developer Guide)

Deleting Tasks

The 'DeleteTaskCommand` is used to delete a task. A task can only be deleted if the member who is currently logged in is either the Assignor or the Assignee.
The command object takes in the INDEX of the task to be deleted.

Figure 38 below shows the UML representation of DeleteTaskCommand.

DeleteTaskCommandUML

Figure 38. UML diagram of DeleteTaskCommand.

DeleteTaskCommandParser is responsible for parsing the user input into a DeleteTaskCommand object.
Figure 39 illustrates the sequence in which the parsing is done.

SDforDeleteTaskCommandParser

Figure 39. Sequence Diagram for DeleteTaskCommand parsing.

The high-level sequence of events is shown below in Figure 40.

SDforDeleteTask

Figure 40. Sequence Diagram for deleting a task.

Design Considerations

Aspect: Who can delete tasks?

  • Alternative 1 (current choice): Only Assignors can delete tasks.

    • Pros: It improves accountability of the club.

    • Cons: All the workload falls on the Assignor.

  • Alternative 2: Assignor or Assignee can delete task.

    • Pros: The workload is evenly distributed.

    • Cons: Reduces transparency of club and accountability of club members.

End of Extract (from Developer Guide)

4. Changing task assignee

4.1 Contribution to User Guide

Start of Extract (from User Guide)

Changing the assignee of a task : changeassignee (Since v1.5rc)

Changes the assignee of a task in Club Connect.
Format: changeassignee INDEX m/MATRIC_NUMBER
Alias: assignee

  • INDEX must be a positive integer 1, 2, 3, …​

  • You cannot change the Assignee to a member who has already been assigned a task with identical attributes by another Exco member.

  • Passing the current Assignee of the task in the input throws an error as there is no change.

  • No duplicate tasks are allowed.

This command is only for Exco members.

Examples:

  • changeassignee 1 m/A0123456H
    Changes the assignee of the 1st task to A0123456H in the task listing.

  • assignee 3 m/A6656789H
    Changes the assignee of the 3rd task to A6656789H in the task listing.

End of Extract (from User Guide)

4.2 Contribution to Develop Guide

Start of Extract (from User Guide)

Assigning Tasks

Assigning tasks can be accomplished with the AssignTaskCommand. Tasks are assigned to members through the Matric Number attribute.

Figure 35 below shows the UML representation of AssignTaskCommand.

AssignTaskCommandUML

Figure 35. UML diagram of AssignTaskCommand.

The implementation of assigning tasks is similar to that of adding tasks. The only difference is that the Assignor is set to the Matric Number of the member who is currently logged in.

The parsing of an AssignTaskCommand is performed by the AssignTaskCommandParser.
Figure 36 shows the flow of parsing an AssignTaskCommand object:

SDforAssignTaskCommandParser

Figure 36. Sequence Diagram for AssignTaskCommand parsing.

Figure 37 depicts the high-level sequence of events that take place.

SDforAssignTask

Figure 37. Sequence Diagram for assigning a task.

Design Considerations

Aspect: Displaying similar tasks for different Assignees

  • Alternative 1 (current choice): Make a copy of the task for every new Assignee if all other parameters are same.

    • Pros: Easy to implement

    • Cons: Clutters the TaskListPanel because of redundancies.

  • Alternative 2: Maintain a list of Assignee s in a task .

    • Pros: Reduces clutter in the TaskListPanel and is easy on the eye.

    • Cons: Relatively difficult to implement.

End of Extract (from User Guide)

5. Viewing Tasks

5.1 Contribution to User Guide

Start of Extract (from User Guide)

Viewing all tasks in Club Connect : viewalltasks (Since v1.4)

Displays all the tasks created/assigned in Club Connect. This is a command that can be used by Exco members to monitor all the tasks in the club.
Format: viewalltasks
Alias: alltasks

This command is for Exco members only.

Viewing tasks assigned to or assigned by you : viewmytasks (Since v1.4)

Display all tasks created/assigned by the currently logged-in member in Club Connect.

The main purpose of this command is to enable Exco members to toggle between all tasks and those related to them.

Format: viewmytasks
Alias: mytasks

End of Extract (from User Guide)

5.2 Contribution to Developer Guide

Start of Extract (from Developer Guide)

Viewing All Tasks

Exco members can view all the tasks in Club Connect using the ViewAllTasksCommand.

The high-level sequence of events on executing the ViewAllTasksCommand is described below in Figure 47.

SDforViewAllTasks

Figure 47. Sequence Diagram for viewing all tasks.

Viewing My Tasks

Exco members need a way to toggle between all tasks in Club Connect and the tasks that are related to them (i.e. tasks that they have assigned or been assigned to). This is achieved by the ViewMyTasksCommand.

The Predicate used is TaskIsRelatedToMemberPredicate. Here is the overridden TaskIsRelatedToMemberPredicate#test method.

@Override
public boolean test(Task task) {
    return member.getMatricNumber().toString().equalsIgnoreCase(task.getAssignor().getValue())
            || member.getMatricNumber().toString().equalsIgnoreCase(task.getAssignee().getValue());
}

The sequence diagram of the viewmytasks command is shown below in Figure 48.

SDforViewMyTasks

Figure 48. Sequence Diagram for viewing tasks of the currently logged-in member.

End of Extract (from Developer Guide)