db __enter__ *always* either returns the db or throws, we no longer need to check for None

Author: ngc92

src/discord-cluster-manager/api/utils.py …discord-cluster-manager/api/api_utils.pysrc/discord-cluster-manager/api/utils.py renamed to src/discord-cluster-manager/api/api_utils.py src/discord-cluster-manager/api/utils.py renamed to src/discord-cluster-manager/api/api_utils.py

@@ -10,12 +10,13 @@
 
 from backend import KernelBackend
 from consts import SubmissionMode
-from fastapi import Depends, FastAPI, Header, HTTPException, UploadFile
-from fastapi.responses import StreamingResponse
+from fastapi import Depends, FastAPI, Header, HTTPException, Request, UploadFile
+from fastapi.responses import JSONResponse, StreamingResponse
 from leaderboard_db import LeaderboardRankedEntry
 from submission import SubmissionRequest
+from utils import KernelBotError
 
-from .utils import _handle_discord_oauth, _handle_github_oauth, _run_submission
+from .api_utils import _handle_discord_oauth, _handle_github_oauth, _run_submission
 
 # yes, we do want  ... = Depends() in function signatures
 # ruff: noqa: B008
@@ -60,18 +61,18 @@ def init_api(_backend_instance: KernelBackend):
     backend_instance = _backend_instance
 
 
+@app.exception_handler(KernelBotError)
+async def kernel_bot_error_handler(req: Request, exc: KernelBotError):
+    return JSONResponse(status_code=exc.http_code, content={"message": str(exc)})
+
+
 @contextmanager
 def get_db():
     """Database context manager with guaranteed error handling"""
     if not backend_instance:
         raise HTTPException(status_code=500, detail="Bot instance not initialized")
 
-    if not hasattr(backend_instance, "leaderboard_db"):
-        raise HTTPException(status_code=500, detail="Database not initialized")
-
     with backend_instance.db as db:
-        if db is None:
-            raise HTTPException(status_code=500, detail="Database connection failed")
         yield db
 
 

src/discord-cluster-manager/api/main.py

@@ -57,7 +57,7 @@ def disconnect(self):
         self.cursor = None
         self.connection = None
 
-    def __enter__(self):
+    def __enter__(self) -> "LeaderboardDB":
         """Context manager entry"""
         if self.connection is not None:
             self.refcount += 1
@@ -66,7 +66,8 @@ def __enter__(self):
         if self.connect():
             self.refcount = 1
             return self
-        return None
+
+        raise KernelBotError("Could not connect to database", code=500)
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         """Context manager exit"""

src/discord-cluster-manager/leaderboard_db.py

@@ -30,8 +30,9 @@ class KernelBotError(Exception):
     risk of leaking internal bot details.
     """
 
-    def __init__(self, message):
+    def __init__(self, message, code: int = 400):
         super().__init__(message)
+        self.http_code = 400
 
 
 def get_github_branch_name():