Initial draft

src/main.py

@@ -0,0 +1,130 @@
+from fastapi import FastAPI, Depends, HTTPException, Request, Response
+from fastapi.responses import JSONResponse
+from fastapi.security.api_key import APIKeyHeader
+from starlette.exceptions import HTTPException as StarletteHTTPException
+from typing import Dict
+from pydantic import BaseModel
+from validator import verify_api_key
+from db_module import get_db, create_connection_pool, close_connection_pool, start_healthcheck_thread
+from simple_logger_handler import setup_logger, LOG_LEVEL
+from rabbitmq_handler import RabbitMQProducer
+import uvicorn
+from contextlib import asynccontextmanager
+from metrics_server import REQUEST_COUNTER
+import asyncio
+from uvicorn_logger_config import LOGGING_CONFIG
+from secret_manager import cleanup_secret_files
+
+logger = setup_logger(__name__)
+api_key_header_internal = APIKeyHeader(name="X-API-Key-Internal")
+
+class Notification(BaseModel):
+	receipent_user_id : int
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+	logger.info("Starting application...")
+
+	logger.info("Creating MySQL connection pool...")
+	create_connection_pool("ApiInternalPool")
+	start_healthcheck_thread()
+	logger.info("MySQL healthcheck thread started.")
+
+	producer = RabbitMQProducer()
+
+	try:
+		logger.info("Starting RabbitMQ producer...")
+		await producer.connect()
+		app.state.rmq_producer = producer
+		logger.info("[FastAPI] RabbitMQ producer initialized.")
+
+		SECRET_PATHS = frozenset({
+			"/etc/secrets/db_username",
+			"/etc/secrets/db_password",
+			"/etc/secrets/rmq_username",
+			"/etc/secrets/rmq_password"
+		})
+		cleanup_secret_files(SECRET_PATHS)
+
+		yield
+	finally:
+		logger.info("Closing RabbitMQ producer...")
+		await producer.close()
+
+		logger.info("Closing MySQL connection pool...")
+		close_connection_pool()
+
+api = FastAPI(
+		title="Internal Notifier API",
+		description="API to forward messages to RabbitMQ",
+		version="1.0.0",
+		lifespan=lifespan
+)
+
+@api.middleware("http")
+async def prometheus_middleware(request: Request, call_next):
+	logger.debug(f"Incoming request: {request.method} {request.url.path}")
+	status = 500
+	try:
+		response = await call_next(request)
+		status = response.status_code
+		logger.debug(f"Request processed with status: {status}")
+	except Exception as e:
+		logger.exception(f"Exception during request processing: {e}")
+		raise
+	finally:
+		REQUEST_COUNTER.labels(request.method, request.url.path, status).inc()
+		logger.debug(f"Prometheus counter incremented: {request.method} {request.url.path} {status}")
+	return response
+
+def verify_api_key_dependency_internal(db=Depends(get_db), api_key: str = Depends(api_key_header_internal)) -> str:
+	logger.debug(f"Verifying internal API key: {api_key}")
+	cursor = db.cursor()
+	cursor.execute("SELECT program_name, api_key FROM internal_api_keys WHERE status = 'active'")
+	for program_name, hashed_key in cursor.fetchall():
+		if verify_api_key(api_key=api_key, hashed=hashed_key):
+			logger.debug(f"API key verified for program: {program_name}")
+			return program_name
+	logger.warning("Internal API key verification failed")
+	raise HTTPException(status_code=403, detail="Unauthorized")
+
+@api.exception_handler(StarletteHTTPException)
+async def custom_http_exception_handler(request,exc):
+	logger.debug(f"Handling HTTP exception: {exc}")
+	if exc.status_code == 404:
+		return JSONResponse(
+			status_code=403,
+			content={"detail": "Unauthorized"}
+		)
+	return JSONResponse(
+		status_code=exc.status_code,
+		content={"detail": exc.detail}
+	)
+
+@api.get("/notifications/pull")
+async def receive_notifications(
+	notification_data: Notification,
+	request: Request,
+	db = Depends(get_db),
+	program_name: str = Depends(verify_api_key_dependency_internal)
+):
+
+	logger.info(f"Received notifcation data from {program_name} for RMQ")
+
+	messages = await request.app.state.rmq_producer.fetch_messages()
+	logger.info("Successfully retrieved messages for ")
+	print (messages)
+
+async def start_servers():
+	logger.debug("Starting FastAPI and metrics servers")
+	config_main = uvicorn.Config("main:api", host="0.0.0.0", port=8101, log_level=LOG_LEVEL.lower(), log_config=LOGGING_CONFIG)
+	config_metrics = uvicorn.Config("metrics_server:metrics_api", host="0.0.0.0", port=9000, log_level=LOG_LEVEL.lower(), log_config=LOGGING_CONFIG)
+
+	server_main = uvicorn.Server(config_main)
+	server_metrics = uvicorn.Server(config_metrics)
+
+	await asyncio.gather(server_main.serve(), server_metrics.serve())
+	logger.debug("Servers started")
+
+if __name__ == "__main__":
+	asyncio.run(start_servers())