switched from prints to loggers with log levels

server/app.py

@@ -1,5 +1,7 @@
 from flask import Flask, jsonify, render_template
+import logging
 import os, sys, threading, time
+
 from src.parser import (
     get_this_semesters_sessions,
     calculate_totals,
@@ -9,19 +11,22 @@ from src.parser import (
 from src.cache import Cache
 
 app = Flask(__name__)
+logging.basicConfig(level=logging.INFO)
 sessions_cache = Cache()
 
 REFETCH_MINUTES = os.environ.get("REFETCH_INTERVAL_MINUTES", "5")
 if not REFETCH_MINUTES.isdigit():
-    print("Invalid refetch interval")
+    app.logger.error("Invalid refetch interval")
     sys.exit(1)
 REFETCH_SECONDS = int(REFETCH_MINUTES) * 60
 
 # initial data fetch (required to work)
 try:
-    sessions_cache.set(get_this_semesters_sessions())
+    sessions = get_this_semesters_sessions()
+    sessions_cache.set(sessions)
+    app.logger.info(f"Fetched {len(sessions)} sessions from calDAV server")
 except Exception:
-    print("Failed to fetch from calDAV server.")
+    app.logger.exception("Failed to fetch from calDAV server.")
     sys.exit(1)
 
 # web ui
@@ -55,9 +60,9 @@ def fetch_job():
         time.sleep(REFETCH_SECONDS)
         try:
             sessions_cache.set(get_this_semesters_sessions())
-            print("Successfully fetched data from calDAV")
+            app.logger.info(f"Fetched {len(sessions)}  sessions from calDAV server")
         except Exception:
-            print("Failed to refresh from calDAV server, keeping old data.")
+            app.logger.warning("Failed to fetch from calDAV server, keeping old data")
 
 if __name__ == "__main__":
     if os.environ.get("WERKZEUG_RUN_MAIN") == "true" or not app.debug:

server/src/parser.py

@@ -1,9 +1,13 @@
+import logging
+
 from dotenv import load_dotenv
 from datetime import datetime, timedelta, date, time as dtime
 
 from zoneinfo import ZoneInfo
 import caldav, os, random
 
+logger = logging.getLogger(__name__)
+
 # load settings from .env
 try:
     load_dotenv()
@@ -14,7 +18,7 @@ try:
     SEMESTER_STARTS = os.environ["SEMESTER_STARTS"]
     if SEMESTER_STARTS: SEMESTER_STARTS = SEMESTER_STARTS.split(",")
 except Exception:
-    print("Failed to read settings from .env!\nTake a look at .env.example for the required structure!")
+    logger.error("Failed to read settings from .env!\nTake a look at .env.example for the required structure!")
 
 client = caldav.DAVClient(
     url=CALDAV_URL,
@@ -52,7 +56,7 @@ def get_all_sessions() -> list:
 def get_this_semesters_sessions() -> list:
     sessions = get_all_sessions()
     semester_start = get_current_semester_start()
-    print(f"grabbing sessions since {str(semester_start)}")
+    logger.info(f"keeping sessions after semester start [{str(semester_start)}]")
 
     if not semester_start: 
         # no semester starts given, just pass all sessions
@@ -67,7 +71,6 @@ def get_this_semesters_sessions() -> list:
 # or return None if no semesters were specified
 def get_current_semester_start() -> date:
     if not SEMESTER_STARTS: # array of MM-DD strings
-        print("no starts")
         return None
 
     # first check if one the dates was previously this year
@@ -76,7 +79,7 @@ def get_current_semester_start() -> date:
     try:
         dates = [datetime.strptime(str(today.year)+"-"+date_str, "%Y-%m-%d").date() for date_str in SEMESTER_STARTS]
     except Exception:
-        print("Failed to parse semester start date. Falling back to None!")
+        logger.warning("Failed to parse semester start date. Falling back to None!")
         return None
 
     for date in dates:
@@ -93,7 +96,7 @@ def get_current_semester_start() -> date:
     try:
         last_year_dates = [date.replace(year=date.year - 1) for date in dates] 
     except Exception:
-        print("Failed to parse semester start date. Falling back to None!")
+        logger.warning("Failed to parse semester start date. Falling back to None!")
         return None
 
     return max(last_year_dates)