fix: tolerate missing database on startup

Author: arthurhenrique

AGENTS.md

@@ -1,2 +1,2 @@
-- Always run `pytest {{cookiecutter.project_slug}}/tests` and ensure all tests pass after any code changes.
-- Run tests even if not explicitly requested.
+- Always run `pytest {{cookiecutter.project_slug}}/tests` and ensure all tests pass after any code changes, even if not explicitly requested.
+- Always add tests, keep your branch rebased instead of merged, and adhere to the commit message recommendations from https://cbea.ms/git-commit/.

{{cookiecutter.project_slug}}/app/core/events.py

@@ -2,6 +2,9 @@
 
 import joblib
 from fastapi import FastAPI
+from loguru import logger
+from sqlalchemy.exc import OperationalError
+
 from core.config import MEMOIZATION_FLAG
 from db import Base, engine
 
@@ -19,6 +22,9 @@ def create_start_app_handler(app: FastAPI) -> Callable:
     def start_app() -> None:
         if MEMOIZATION_FLAG:
             preload_model()
-        Base.metadata.create_all(bind=engine)
+        try:
+            Base.metadata.create_all(bind=engine)
+        except OperationalError:
+            logger.exception("failed to initialize database")
 
     return start_app

{{cookiecutter.project_slug}}/tests/test_events_and_main.py

@@ -1,4 +1,5 @@
 from fastapi import FastAPI
+from sqlalchemy.exc import OperationalError
 
 from core import events
 from main import get_application
@@ -27,6 +28,12 @@ def fake_preload():
         called["called"] = True
 
     monkeypatch.setattr(events, "preload_model", fake_preload)
+
+    def fake_create_all(*args, **kwargs):
+        raise OperationalError("stmt", {}, Exception("db down"))
+
+    monkeypatch.setattr(events.Base.metadata, "create_all", fake_create_all)
+
     app = FastAPI()
     handler = events.create_start_app_handler(app)
     handler()