Merge pull request #175 from grillazz/174-implement-scheduler

174 implement scheduler

Author: grillazz

README.md

@@ -176,6 +176,7 @@ I've included a few of my favorites to kick things off!
 - **[MAR 15 2024]** add polars and calamine to project :heart_eyes_cat:
 - **[JUN 8 2024]** implement asyncpg connection pool :fast_forward:
 - **[AUG 17 2024]** granian use case implemented with docker compose and rich logger :fast_forward:
+- **[OCT 16 2024]** apscheduler added to project :fast_forward:
 
 <p align="right">(<a href="#readme-top">back to top</a>)</p>
 

app/main.py

@@ -1,6 +1,6 @@
 import asyncpg
-from contextlib import asynccontextmanager
-
+from apscheduler.eventbrokers.redis import RedisEventBroker
+from apscheduler.datastores.sqlalchemy import SQLAlchemyDataStore
 from fastapi import FastAPI, Depends
 from fastapi_cache import FastAPICache
 from fastapi_cache.backends.redis import RedisBackend
@@ -9,11 +9,17 @@
 from app.api.shakespeare import router as shakespeare_router
 from app.api.stuff import router as stuff_router
 from app.config import settings as global_settings
+from app.database import engine
 from app.utils.logging import AppLogger
 from app.api.user import router as user_router
 from app.api.health import router as health_router
 from app.redis import get_redis, get_cache
 from app.services.auth import AuthBearer
+from app.services.scheduler import SchedulerMiddleware
+
+from contextlib import asynccontextmanager
+
+from apscheduler import AsyncScheduler
 
 logger = AppLogger().get_logger()
 
@@ -60,3 +66,16 @@ async def lifespan(_app: FastAPI):
     tags=["Health, Bearer"],
     dependencies=[Depends(AuthBearer())],
 )
+
+_scheduler_data_store = SQLAlchemyDataStore(engine)
+_scheduler_event_broker = RedisEventBroker(
+    client_or_url=global_settings.redis_url.unicode_string()
+)
+_scheduler_himself = AsyncScheduler(_scheduler_data_store, _scheduler_event_broker)
+
+app.add_middleware(SchedulerMiddleware, scheduler=_scheduler_himself)
+
+
+# TODO: every not GET meth should reset cache
+# TODO: every scheduler task which needs to act on database should have access to connection pool via request - maybe ?
+# TODO: https://stackoverflow.com/questions/16053364/make-sure-only-one-worker-launches-the-apscheduler-event-in-a-pyramid-web-app-ru

app/models/stuff.py

@@ -17,7 +17,9 @@ def compile_sql_or_scalar(func):
     async def wrapper(cls, db_session, name, compile_sql=False, *args, **kwargs):
         stmt = await func(cls, db_session, name, *args, **kwargs)
         if compile_sql:
-            return stmt.compile(dialect=postgresql.dialect(), compile_kwargs={"literal_binds": True})
+            return stmt.compile(
+                dialect=postgresql.dialect(), compile_kwargs={"literal_binds": True}
+            )
         result = await db_session.execute(stmt)
         return result.scalars().first()
 

app/models/user.py

@@ -27,12 +27,12 @@ def password(self):
     @password.setter
     def password(self, password: SecretStr):
         _password_string = password.get_secret_value().encode("utf-8")
-        self._password = bcrypt.hashpw(
-            _password_string, bcrypt.gensalt()
-        )
+        self._password = bcrypt.hashpw(_password_string, bcrypt.gensalt())
 
     def check_password(self, password: SecretStr):
-        return bcrypt.checkpw(password.get_secret_value().encode("utf-8"), self._password)
+        return bcrypt.checkpw(
+            password.get_secret_value().encode("utf-8"), self._password
+        )
 
     @classmethod
     async def find(cls, database_session: AsyncSession, where_conditions: list[Any]):

app/services/scheduler.py

@@ -0,0 +1,41 @@
+from datetime import datetime
+
+from sqlalchemy import text
+from starlette.types import ASGIApp, Receive, Scope, Send
+from apscheduler import AsyncScheduler
+from apscheduler.triggers.interval import IntervalTrigger
+
+from app.database import AsyncSessionFactory
+from app.utils.logging import AppLogger
+
+logger = AppLogger().get_logger()
+
+
+async def tick():
+    async with AsyncSessionFactory() as session:
+        stmt = text("select 1;")
+        logger.info(f">>>> Be or not to be...{datetime.now()}")
+        result = await session.execute(stmt)
+        logger.info(f">>>> Result: {result.scalar()}")
+        return True
+
+
+class SchedulerMiddleware:
+    def __init__(
+        self,
+        app: ASGIApp,
+        scheduler: AsyncScheduler,
+    ) -> None:
+        self.app = app
+        self.scheduler = scheduler
+
+    async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
+        if scope["type"] == "lifespan":
+            async with self.scheduler:
+                await self.scheduler.add_schedule(
+                    tick, IntervalTrigger(seconds=25), id="tick-sql-25"
+                )
+                await self.scheduler.start_in_background()
+                await self.app(scope, receive, send)
+        else:
+            await self.app(scope, receive, send)

app/utils/logging.py

@@ -20,5 +20,6 @@ def get_logger(self):
 class RichConsoleHandler(RichHandler):
     def __init__(self, width=200, style=None, **kwargs):
         super().__init__(
-            console=Console(color_system="256", width=width, style=style, stderr=True), **kwargs
+            console=Console(color_system="256", width=width, style=style, stderr=True),
+            **kwargs
         )