CSC/ECE 517 Spring 2025 - E2516. Reimplement teams users controller.rb

E2516: Reimplement teams_users_controller.rb

Overview

Our goal for this project is to reimplement the TeamUsersController and change it to TeamsParticipantsController thereby strictly following DRY and SOLID principles. Presently, the TeamsUsersController is responsible for managing the interactions between teams and participants. Teams are associated with assignments and courses while participants are associated with these.

As of now, the controller achieves below mentioned functionalities:

1. Listing team members

2. Adding participants to teams

3. Removing participants from teams

4. Updating participants' duties within teams

5. Providing autocomplete suggestions for participant names when adding new members

6. Bulk deletion of team members

For the next project deliverable, we plan to achieve below mentioned functionalities:

1. Modifying the TeamsUsersController to TeamsParticipantsController and respectively modifying the associations and related methods and classes

2. We plan to achieve separation of concerns between models and classes and aim to minimize coupling

3. More test cases and test suites will be implement to test the robustness and effectiveness of the changes modified

4. Achieving code readability and maintainability by providing descriptive comments wherever necessary and maintaining consistent naming conventions for variables

Problem Description

Currently our controller presents with below mentioned major issues:

1. Incorrect Association Representation: The TeamsUser model links a User with a Team , not taking into consideration whether the User is assigned with a course or an assignment and generating ambiguity.

2. Violation of SOLID/DRY Principles: The methods in the controllers are very long and contain unnecessary logic and redundant code

3. Tight Coupling: Currently, there is a business logic code that resides in the model whereas it should have been placed in the controller. This results in a higher coupling and introduces difficulties in the future while modifying code.

4. Inconsistent code quality: Many places in the code have inconsistent naming conventions for the variables.

5. Insufficient Testing: Currently, testing has not been performed to a great extent and so the effectiveness of the existing codebase cannot be determined.

Scope of Work

The current work will involve the below implementation effort:

1. Model Refactoring

• Replace TeamsUsers controller with TeamsParticipants
• Update the database association structure to link TeamsParticipant with Partipant and Team

2. Controller Redesign

• Reimplementing a new TeamsParticipantsController which handles associations between teams and participants and achieves all functionalities listed in above section
• Ensure controller actions focus on request/response handling and delegating business logic to models

3. Create Method Refactor

• Breaking down create method in the controller into smaller, reusable, testable private methods
• Eliminate code duplication and unnecessary nesting

4. Model Enhancements

• Using the concept of polymorphism to clearly handle team membership and association rules
• Introducing checks related to whether a user is part of multiple teams and ensuring this is satisfied only in case of a mentor who can be assigned multiple teams

5. Code Quality Improvements

• Ensuring consistent naming conventions for variables
• Descriptive comments to make code more reliable and understandable
• Applying code best practises throughout codebase to ensure consistency

6. Testing

• Including RSpec tests for each controller method (e.g. index, create, delete etc.)
• Implement tests in models wherever additional business logic has been added
• Perform manual testing to ensure feature completeness and correctness

7. Documentation

• A detailed documentation providing the behavior of the controller and what it tries to achieve
• It should also include the associations between different entities and model and controller interactions

Summary of Refactor

• Replaced all references to TeamsUser with TeamsParticipant.

• Refactored long methods (especially create) into smaller private methods.

• Moved business logic to AssignmentTeam and MentoredTeam where appropriate (e.g., mentor-specific rules).

• Removed unnecessary nesting in methods like create.

• Improved naming conventions for all variables.

• Enhanced comments to explain functionality clearly.

• Ensured SOLID Principles are followed across all code.

• Wrote new unit and integration tests for controller methods.

Proposed Flow for Major Methods

index

Input: team_id

Action: Find team → Retrieve associated participants → Render list (JSON or HTML view).

Notes: Simplicity focus: Only data retrieval, no complex logic.

create

Input: Participant information, team_id

Steps:

Validate participant (exists, belongs to assignment/course). Check team eligibility: If participant is already on another team → Validate mentor exception rules (handled in model). Create TeamsParticipant record linking the participant and team. Handle success/failure gracefully with appropriate responses. Important: Keep business rules outside the controller wherever possible (delegate to model methods).

destroy

Input: teams_participant_id

Action: Remove participant from the team cleanly, handling foreign key constraints.

autocomplete_participants

Input: assignment_id, search string

Action: Return a list of matching participants for the given assignment.

bulk_delete

Input: List of participant IDs

Action: Mass remove participants from their teams, validate permissions.

Helper Methods (Private)

find_team

find_participant

validate_participant_eligibility

add_participant_to_team

remove_participant_from_team

mentor_eligibility_check (Delegated to AssignmentTeam / MentoredTeam)

Each method will have a clear single responsibility and promote reuse across the controller.

Notes on Migration

All foreign keys linking teams to users will point through TeamsParticipants, not TeamsUsers.

Update any related services or background jobs that previously depended on TeamsUser.

Backward compatibility should be evaluated carefully to avoid breaking existing assignments or teams during the migration phase.

Files Changed

TeamsParticipantsController

Method	Change	Reason
action_allowed?	No Change	Determines if the current user has the necessary privileges to perform the requested action.
auto_complete_for_user_name	No Change	Provides a list of possible team members based on a partial name search for autocomplete functionality.
update_duties	No Change	Updates the duty assigned to a participant within a team and redirects to the student's team view.
list	No Change	Displays all participants of a specific team with pagination support.
new	No Change	Prepares the form for adding a new participant.
create	Refactored	Validates eligibility before adding a participant; delegates business logic.
delete	Refactored	Removes participant cleanly with undo option.
delete_selected	New	Bulk deletes multiple participants from a team.
user_not_found_message (private)	New	Returns a specific message if a user is not found.
valid_participant? (private)	New	Checks eligibility of participant for assignment/course.
participant_not_found_message (private)	New	Provides feedback if participant not linked to assignment/course.

AssignmentTeam.rb

Method	Change	Reason
user_id(current_user = nil)	Modified	Added optional current_user param for better flexibility.
set_current_user	Removed	Logic merged into user_id.
includes?(participant)	Retained (Minor rewording)	Direct comparison with updated participant fetching logic.
parent_model	Retained	Returns 'Assignment' as parent model.
self.parent_model(id)	Removed	Responsibility moved elsewhere for separation of concerns.
fullname	Removed	Deemed unnecessary alias.
review_map_type	Removed	Hardcoding removed to reduce tight coupling.
prototype	Removed	Not needed under Rails ActiveRecord conventions.
assign_reviewer	Modified	Extracted review map creation into create_review_map.
create_review_map	New	Dedicated method for creating review maps.
get_reviewer	Removed	Reviewer assignment simplified.
reviewed_by?	Modified	Now uses ReviewResponseMap.exists? for better DB efficiency.
topic	Removed	Responsibility split for cleaner structure.
has_submissions?	Retained	Basic file/submission existence checks.
participants	Modified	Refactored using TeamsParticipant.team_members(id).
add_participant	Modified	Creates a TeamsParticipant directly.
delete & destroy	Removed	Simplified elsewhere.
first_member	Removed	SRP enforcement.
submitted_files(path)	Removed	File access logic shifted to service.
import/export methods	Removed	Responsibility moved to helpers/services.
copy(course_id)	Removed	Refactored externally.
hyperlinks	Removed	Delegated to service.
submit_hyperlink(hyperlink)	Modified (Delegated)	Handled by TeamFileService.
remove_hyperlink(hyperlink)	Modified (Delegated)	Handled by TeamFileService.
files(directory)	Removed	File traversal extracted.
team(participant)	Removed	Moved to higher-level service.
export_fields(options)	Removed	Offloaded for SRP.
remove_team_by_id(id)	Removed	Refactored.
path	Removed	File path responsibility shifted.
set_student_directory_num	Removed	Directory numbering moved.
received_any_peer_review?	Removed	Simplified elsewhere.
most_recent_submission	Retained (Optimized)	Improved query efficiency.
get_logged_in_reviewer_id(current_user_id)	Removed	Participant-reviewer handling refactored.
current_user_is_reviewer?(current_user_id)	Removed	Responsibility simplified.
create_new_team(user_id, signuptopic)	Modified (Simplified)	Refactored for better exception handling.

MentoredTeam.rb

Method	Change	Reason
add_member(user, _assignment_id = nil)	Refactored	Broken into modular private methods for adding users and assigning mentors.
import_team_members(row_hash)	Refactored	Improved to skip blanks, safe user lookup, and error handling.
can_add_member?(user)	New	Private method for team capacity and mentor assignment validation.
add_team_user(user)	New	Cleanly adds a TeamsUser.
add_participant_to_team(user)	New	Adds participant based on assignment.
assign_mentor_if_needed(_assignment_id)	New	Ensures no duplicate mentors are assigned.
mentor_assignment_valid?(user)	New	Validates mentor assignment rules.
user_not_in_team?(user)	New	Checks if user is already part of the team.
find_or_raise_user(teammate)	New	Finds user or raises informative ImportError.

TeamsParticipants Model

Aspect	Change	Reason
Association	New	Establishes direct link between Participant and Team to maintain integrity.
team_members	New	Retrieves all users associated through participants.
remove_participant_from_team	New	Safely removes participant from team.
username delegation	New	Delegates access to participant's username.
Integrity	New	Ensures only valid assignment participants can join teams.
Maintainability	New	Designed to align with SOLID principles and Rails best practices.

Testing Plan

We plan to cover the reimplementation and refactoring of the following:

• AssignmentTeam
• MentoredTeam
• TeamsParticipantsController
• TeamsParticipant model

We use RSpec for model, controller, and request specs. API tests are also included where applicable. Both positive and negative test cases are included to ensure robust functionality, along with validation checks and authorization verifications.

AssignmentTeam Model Tests

#	Method	Test Description
1	user_id	Verify that the correct user ID is returned; prioritize current user if available.
2	includes?	Check if a given participant is part of the team.
3	parent_model	Ensure the parent model returns "Assignment".
4	assign_reviewer	Test reviewer assignment creation and error handling when assignment is not found.
5	create_review_map	Confirm a new ReviewResponseMap record is created successfully.
6	reviewed_by?	Verify if a reviewer has reviewed the team; test both true and false scenarios.
7	participants	Ensure the correct participants are retrieved via TeamsParticipant.
8	add_participant	Confirm that a participant is added, and prevent duplicate addition.
9	create_new_team	Ensure that a new team-user linkage, sign-up, and nodes are created properly.
10	submit_hyperlink	Verify delegation to TeamFileService for hyperlink submission.
11	remove_hyperlink	Verify delegation to TeamFileService for hyperlink removal.
12	has_submissions?	Check behavior when team has submissions and when it doesn't.
13	most_recent_submission	Ensure the most recent submission is retrieved based on updated_at.

MentoredTeam Model Tests

#	Method	Test Description
1	import_team_members	Ensure team members are imported from a list correctly.
2	find_or_raise_user	Test for successful user lookup and error raising if user not found.
3	user_not_in_team?	Confirm whether a user is already in the team or not.
4	mentor_assignment_valid?	Verify that a mentor can be assigned properly and prevent duplicate mentors.
5	add_member	Ensure user is added successfully and prevent re-adding existing team members.
6	can_add_member?	Verify team capacity check before adding a member.
7	add_team_user	Ensure that a TeamsUser is created and linked correctly.
8	add_participant_to_team	Confirm that a participant is correctly linked to the team.
9	assign_mentor_if_needed	Validate that mentor is assigned only when needed (no double assignment).

TeamsParticipantsController Tests

#	Method	Test Description
1	valid_participant?	Confirm existence check for a participant; return true/false accordingly.
2	update_duties	Test participant duty update flow and ensure a redirect occurs.
3	user_not_found_message	Validate that a proper flash message is returned when a user isn't found.
4	participant_not_found_message	Validate correct error message if participant isn't linked.
5	create	Confirm that creating a TeamsParticipant increases record count.
6	list	Test that the participant list view renders correctly.
7	action_allowed?	Ensure access control is enforced based on user roles (admin/TA/student).
8	delete	Confirm deletion of a TeamsParticipant entry works correctly.
9	auto_complete_for_user_name	Verify that JSON autocomplete results are returned based on user input.
10	new	Test that the new participant view loads successfully.
11	delete_selected	Ensure multiple TeamsParticipant records can be deleted at once.

TeamsParticipant Model Tests

#	Method	Test Description
1	Associations	Ensure that a TeamsParticipant correctly belongs to a team and participant.
2	Validations	Confirm presence validations on team and participant relationships.
3	team_members	Validate fetching all team members given a team ID.
4	participant?	Verify participant existence check for a given user; test positive and negative cases.

TeamsParticipants API (Request Specs)

#	Endpoint	Test Description
1	POST /teams_participants	Ensure a participant is added via API and redirects successfully.
2	DELETE /teams_participants/:id	Ensure a participant is deleted via API and redirects successfully.

Pull request

• Pull Request(https://github.com/expertiza/reimplementation-back-end/pull/170)

Mentor

• Vihar Manojkumar Shah(vshah23@ncsu.edu)

Team Members

• Manav Kamdar (mkamdar@ncsu.edu)
• Aditya Singh (asingh78@ncsu.edu)
• Shivang Patel (spatel74@ncsu.edu)