API design

User Sign-Up:
- Endpoint: /user/signUp
- Method: POST
- Request Body:
- { "username": "XYZ", "password": "Encrypted Text"}
- Response:
  - 200 OK if successful
  - Error message in case of failure (e.g., username already taken).
User Login:
- Endpoint: /user/login
- Method: POST
- Request Body:
- { "username": "XYZ", "password": "Encrypted Text"}
- Response:
- { "token": "Auth_Token", "expiresAt": "Expiration Time"}
- Note: The token returned should be used for authenticating further requests.
Game Play Request:
- Endpoint: /game/playRequest
- Method: POST
- Request Body:
- { "type": "Type of Game", "color": "Blue", "preferences": { "time": "Max Time Limit", "maxRating": "opponent's rating", "minRating": "opponent's rating" }}
- Response:
  - Match found with opponent's details or queue status update.
Move Validation:
- Endpoint: /game/moveValidate
- Method: POST
- Request Body:
- { "pieceType": "Pawn", "currentPosition": "e2", "newPosition": "e4"}
- Response:
- { "validate": "ok"}
- Note: This endpoint confirms a move's validity according to the chess rules.