Backend Rewrite - Add friend routes

[lhvy]

• Send friend request (using friend code)
• Cancel friend request
• See outgoing requests
• See incoming requests
• Accept request
• Reject request
• Remove existing friend
• Reset friend code

[fritzrehde]

here are some notes i took, i'm kinda new to db design so most of this is more data structure focussed rather than db focussed, you'll have to translate into db tables properly:

need to support:

Friend requests

DB table

FriendRequest:
from user: user id
to user: user id

need to support functions

send friendship request(from user, to user) -> Request
approve incoming request(incoming request)
reject incoming request(incoming request)
cancel outgoing request(outgoing request)
see incoming requests
see outgoing requests

Friend

DB table

V1:
Friend:
user a: user id
used b: user id

V2:
Friend:
hashmap (db equivalent) from user -> set of their friends

need to support functions

get all friends(user id) -> List[Friend]
two users are friends(user a, user b) -> bool

we care about the speed of both of these

[rfquin]

10/07/2025 Dev-Session Discussion

Decided on this layout (option #2).

This will involve a table that we 'manually' look at to resolve friendships:

+--------+---------+------------+-----------------------------------------+
| Field  | Type    | Key        | Notes                                   |
+--------+---------+------------+-----------------------------------------+
| id     | INT     | PK, UUID   | Primary Key, UUID                       |
| uid1   | INT     | FK         | Foreign Key to Users table (User 1)     |
| uid2   | INT     | FK         | Foreign Key to Users table (User 2)     |
| state  | ENUM    |            | {'req_user1', 'req_user2', 'mutual'}    |
+--------+---------+------------+-----------------------------------------+

rule: uid1 < uid2
We'll ignore relational magic until this mpp is finished

[rfquin]

Complete friend routes:
raw impl:
=> Send friend request (API ROUTE => friendcode if match in db => complete request)
Add friendcode to user generation (random generated string of fixed side)

AND reset friendcode

frontend beta figma viz. @sunnyyuqingchen

[rfquin]

How to deal with prisma's unsupported check feature that we rely on for ordering

https://www.wking.dev/guides/how-to-add-a-check-constraint-in-prisma