Friends System

Campus Connect features a fully functional friend system allowing users to:

• Send, accept, or deny friend requests
• Cancel sent requests
• Remove confirmed friends
• Block or unblock users
• View all friend-related lists

All logic is handled through the FriendsService, with routes protected by AuthGuard.

Warning

Not all features are implemented on the frontend yet

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Schema

• friends: confirmed mutual connections
• friendRequests: incoming requests
• sentFriendRequests: outgoing pending requests
• blockedUsers: users this user has blocked

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Friend API Endpoints

All endpoints require a valid session and are guarded by AuthGuard.

Send Friend Request

POST /friends/request

{ "target": "bob@example.com" }

• target can be user ID, email, or username
• Cannot send to self
• Cannot send to already-friended user
• Cannot send if already pending

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Accept Friend Request

POST /friends/accept

{ "target": "bob@example.com" }

• Moves user to friends
• Removes from friendRequests and their sentFriendRequests

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Deny Friend Request

POST /friends/deny

{ "target": "bob@example.com" }

• Simply removes the incoming request
• No notification sent

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Cancel Friend Request

POST /friends/cancel

{ "target": "bob@example.com" }

• Removes from your sentFriendRequests
• Removes you from their friendRequests

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Remove Friend

POST /friends/remove

{ "target": "bob@example.com" }

• Removes both users from each other's friends lists

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Block User

POST /friends/block

{ "target": "bob@example.com" }

• Adds to blockedUsers
• Automatically removes from:
• friends
• friendRequests
• sentFriendRequests

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Unblock User

POST /friends/unblock

{ "target": "bob@example.com" }

• Removes target from blockedUsers

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Fetch Lists

Friends List

POST /friends/friendsList

Response:

{
  "friends": [
    { "id": "abc123", "username": "bob" },
    { "id": "xyz456", "username": "carol" }
  ]
}

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Incoming Requests

POST /friends/getIncomingRequests

Response:

{
  "requests": [
    { "id": "xyz456", "username": "carol" }
  ]
}

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Sent Requests

POST /friends/getSentRequests

Response:

{
  "requests": [
    { "id": "bob123", "username": "bob" }
  ]
}

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Blocked Users

POST /friends/getBlockedUsers

Response:

{
  "blockedUsers": [
    { "id": "block1", "username": "enemy" }
  ]
}

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Validation & Errors

Scenario	Error
Send to self	400 Bad Request
Already friends	400 Bad Request
Already sent request	400 Bad Request
No incoming request to accept	400 Bad Request
Remove non-friend	400 Bad Request
Blocked already	400 Bad Request
Unblock non-blocked	400 Bad Request
Nonexistent user	404 Not Found

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Notes

• The system uses MongoDB array fields for relationships
• All lookups are done using flexible findByIdentifier():
  • Accepts ID, email, or username
• Notifications are sent (real-time) when:
  • A request is received
  • A request is accepted