added fetch job which updates the data every n minutes (set by config value)

server/.env.example

@@ -8,6 +8,9 @@ CALDAV_PASS=
 # timezone. for example the default: Europe/Berlin
 TIMEZONE=
 
+# the intervall in which the calendar sessions will be re-read in minutes
+REFETCH_INTERVALL_MINUTES=
+
 # an comma seperated list of semester starts. 
 # Studytime will only count sessions up to the last date in the past
 # format: MM-DD,MM-DD,...

server/app.py

@@ -1,40 +1,66 @@
 from flask import Flask, jsonify, render_template
-from src.fetch_sessions import *
+import os, sys, threading, time
+from src.parser import *
 
 app = Flask(__name__)
 
-sessions = get_this_semesters_sessions()
+try:
+    sessions = get_this_semesters_sessions()
+except Exception:
+    print("Failed to fetch from calDAV server.")
+    sys.exit(1)
 
 # web ui
 @app.route("/")
 def index():
-    labels = [s["subject"] for s in sessions]
-    values = [s["minutes"] for s in sessions]
+    current = list(sessions)
+    labels = [s["subject"] for s in current]
+    values = [s["minutes"] for s in current]
     return render_template(
         "index.html", 
         labels=labels, 
         values=values, 
-        sessions=sessions
+        sessions=current
     )
 
 # internal api
 
 @app.route("/api/dashboard")
 def api_dashboard():
-    totals = calculate_totals(sessions)
+    current = list(sessions)
+    totals = calculate_totals(current)
     return jsonify({
-        "sessions": sessions,
+        "sessions": current,
         "subjectTotals": totals,
-        "dailyMinutes":  get_last_n_days(50, sessions),
-        "stats": get_stats(sessions, totals),
+        "dailyMinutes":  get_last_n_days(50, current),
+        "stats": get_stats(current, totals),
     })
 
 # external api
 
 @app.route("/api/sessions")
 def api_sessions():
-    return jsonify(sessions)
+    current = list(sessions)
+    return jsonify(current)
 
 
+def fetch_job():
+    global sessions
+    while True:
+        time.sleep(20)  # 5 minutes
+        try:
+            sessions = get_this_semesters_sessions()
+            print("Successfully fetched data from calDAV")
+        except Exception:
+            print("Failed to refresh from calDAV server, keeping old data.")
+
 if __name__ == "__main__":
+    if os.environ.get("WERKZEUG_RUN_MAIN") == "true" or not app.debug:
+        # we need this guard because flask runs __main__ twice in debug mode
+        if not os.environ["REFETCH_INTERVALL_MINUTES"].isdigit():
+            print("Invalid refetch interval")
+            sys.exit(1)
+        t = threading.Thread(target=fetch_job, daemon=True)
+        t.start()
+
     app.run(host="0.0.0.0", port=5000, debug=True)

server/src/parser.py

@@ -1,5 +1,5 @@
 from dotenv import load_dotenv
-from datetime import datetime, timedelta, date, time
+from datetime import datetime, timedelta, date, time as dtime
 
 from zoneinfo import ZoneInfo
 import caldav, os, random
@@ -27,7 +27,7 @@ calendar = client.calendar(url=CALDAV_URL)
 # dont know when id even need an all day event but better be safe so why not
 def to_datetime(value):
     if isinstance(value, date) and not isinstance(value, datetime):
-        value = datetime.combine(value, time.min, tzinfo=TIME_ZONE) # just set time to 00:00
+        value = datetime.combine(value, dtime.min, tzinfo=TIME_ZONE) # just set time to 00:00
     return value
 
 # grab ALL sessions and return as array of dicts