actually use fastapi lifetime manager to setup logging

backend/src/logging_config.py

@@ -0,0 +1,56 @@
+"""Sets up global logging configuration for the application."""
+
+import logging
+import os
+
+logger = logging.getLogger(__name__)
+
+
+def configure_logging():
+    """
+    Called at startup of a FastAPI application instance to setup logging. Depending on the environment, it will log to stdout or to Loki.
+    """
+
+    is_debug = os.getenv('DEBUG', "false") == "true"
+    is_kubernetes = os.getenv('KUBERNETES_SERVICE_HOST') is not None
+
+
+    if not is_kubernetes:
+        # in that case we want to log to stdout and also to loki
+        from loki_logger_handler.loki_logger_handler import LokiLoggerHandler
+        loki_url = os.getenv('LOKI_URL')
+        loki_url = "http://localhost:3100/loki/api/v1/push"
+        if loki_url is None:
+            raise ValueError("LOKI_URL environment variable is not set")
+        
+        loki_handler = LokiLoggerHandler(
+            url = loki_url,
+            labels = {'app': 'anyway', 'environment': 'staging' if is_debug else 'production'}
+        )
+
+        logger.info(f"Logging to Loki at {loki_url} with {loki_handler.labels} and {is_debug=}")
+        logging_handlers = [loki_handler, logging.StreamHandler()]
+        logging_level = logging.DEBUG if is_debug else logging.INFO
+        # no need for time since it's added by loki or can be shown in kube logs
+        logging_format = '%(name)s - %(levelname)s - %(message)s'
+
+    else:
+        # if we are in a debug (local) session, set verbose and rich logging
+        from rich.logging import RichHandler
+        logging_handlers = [RichHandler()]
+        logging_level = logging.DEBUG if is_debug else logging.INFO
+        logging_format = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+
+
+
+    logging.basicConfig(
+        level = logging_level,
+        format = logging_format,
+        handlers = logging_handlers
+    )
+
+    # also overwrite the uvicorn loggers
+    logging.getLogger('uvicorn').handlers = logging_handlers
+    logging.getLogger('uvicorn.access').handlers = logging_handlers
+    logging.getLogger('uvicorn.error').handlers = logging_handlers
+

backend/src/main.py

@@ -2,7 +2,9 @@
 
 import logging
 from fastapi import FastAPI, HTTPException, Query
+from contextlib import asynccontextmanager
 
+from .logging_config import configure_logging
 from .structs.landmark import Landmark, Toilets
 from .structs.preferences import Preferences
 from .structs.linked_landmarks import LinkedLandmarks
@@ -13,15 +15,26 @@ from .utils.optimizer import Optimizer
 from .utils.refiner import Refiner
 from .cache import client as cache_client
 
-
 logger = logging.getLogger(__name__)
 
-app = FastAPI()
 manager = LandmarkManager()
 optimizer = Optimizer()
 refiner = Refiner(optimizer=optimizer)
 
 
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Function to run at the start of the app"""
+    logger.info("Setting up logging")
+    configure_logging()
+    yield
+    logger.info("Shutting down logging")
+
+
+app = FastAPI(lifespan=lifespan)
+
+
+
 @app.post("/trip/new")
 def new_trip(preferences: Preferences,
              start: tuple[float, float],

backend/src/structs/landmark.py

@@ -1,7 +1,7 @@
 """Definition of the Landmark class to handle visitable objects across the world."""
 
 from typing import Optional, Literal
-from uuid import uuid4
+from uuid import uuid4, UUID
 from pydantic import BaseModel, Field
 
 
@@ -29,12 +29,12 @@ class Landmark(BaseModel) :
         description (Optional[str]): A text description of the landmark.
         duration (Optional[int]): The estimated time to visit the landmark (in minutes).
         name_en (Optional[str]): The English name of the landmark.
-        uuid (str): A unique identifier for the landmark, generated by default using uuid4.
+        uuid (UUID): A unique identifier for the landmark, generated by default using uuid4.
         must_do (Optional[bool]): Whether the landmark is a "must-do" attraction.
         must_avoid (Optional[bool]): Whether the landmark should be avoided.
         is_secondary (Optional[bool]): Whether the landmark is secondary or less important.
         time_to_reach_next (Optional[int]): Estimated time (in minutes) to reach the next landmark.
-        next_uuid (Optional[str]): UUID of the next landmark in sequence (if applicable).
+        next_uuid (Optional[UUID]): UUID of the next landmark in sequence (if applicable).
     """
 
     # Properties of the landmark
@@ -52,7 +52,7 @@ class Landmark(BaseModel) :
     name_en : Optional[str] = None
 
     # Unique ID of a given landmark
-    uuid: str = Field(default_factory=uuid4)
+    uuid: UUID = Field(default_factory=uuid4)
 
     # Additional properties depending on specific tour
     must_do : Optional[bool] = False
@@ -60,7 +60,7 @@ class Landmark(BaseModel) :
     is_secondary : Optional[bool] = False
 
     time_to_reach_next : Optional[int] = 0
-    next_uuid : Optional[str] = None
+    next_uuid : Optional[UUID] = None
 
     def __str__(self) -> str:
         """

backend/src/structs/trip.py

@@ -1,6 +1,6 @@
 """Definition of the Trip class."""
 
-import uuid
+from uuid import uuid4, UUID
 from pydantic import BaseModel, Field
 from pymemcache.client.base import Client
 
@@ -19,9 +19,9 @@ class Trip(BaseModel):
     Methods:
         from_linked_landmarks: create a Trip from LinkedLandmarks object.
     """
-    uuid: str = Field(default_factory=uuid.uuid4)
+    uuid: UUID = Field(default_factory=uuid4)
     total_time: int
-    first_landmark_uuid: str
+    first_landmark_uuid: UUID
 
 
     @classmethod
@@ -31,7 +31,7 @@ class Trip(BaseModel):
         """
         trip = Trip(
             total_time = landmarks.total_time,
-            first_landmark_uuid = str(landmarks[0].uuid)
+            first_landmark_uuid = landmarks[0].uuid
         )
 
         # Store the trip in the cache