From 1c7afafce78f7cb00f3dbf3e9fa7efa29be532ba Mon Sep 17 00:00:00 2001
From: Tim Bendt <timbendt@granular.ag>
Date: Tue, 22 Apr 2025 11:36:29 -0600
Subject: [PATCH] add cred caching and change output dir

---
 .gitignore              |  2 ++
 fetch_outlook_events.py | 52 ++++++++++++++++++++++++++++++++++-------
 2 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/.gitignore b/.gitignore
index 5d85715..1880e23 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,5 @@ output_markdown_files/output_3.md
 output_markdown_files/output_4.md
 output_markdown_files/output_5.md
 output_markdown_files/output_6.md
+token_cache.bin
+output_ics/outlook_events_latest.ics
diff --git a/fetch_outlook_events.py b/fetch_outlook_events.py
index e4902ef..420df1c 100644
--- a/fetch_outlook_events.py
+++ b/fetch_outlook_events.py
@@ -4,6 +4,7 @@ import requests
 import json
 from datetime import datetime
 from dateutil import parser
+from dateutil.tz import UTC
 
 # Read Azure app credentials from environment variables
 client_id = os.getenv('AZURE_CLIENT_ID')
@@ -12,35 +13,54 @@ tenant_id = os.getenv('AZURE_TENANT_ID')
 if not client_id or not tenant_id:
     raise ValueError("Please set the AZURE_CLIENT_ID and AZURE_TENANT_ID environment variables.")
 
+# Token cache
+cache = msal.SerializableTokenCache()
+cache_file = 'token_cache.bin'
+
+if os.path.exists(cache_file):
+    cache.deserialize(open(cache_file, 'r').read())
+
 # Authentication
 authority = f'https://login.microsoftonline.com/{tenant_id}'
 scopes = ['https://graph.microsoft.com/Calendars.Read']
 
-app = msal.PublicClientApplication(client_id, authority=authority)
-flow = app.initiate_device_flow(scopes=scopes)
-if 'user_code' not in flow:
-    raise Exception("Failed to create device flow")
-print(flow['message'])
-token_response = app.acquire_token_by_device_flow(flow)
+app = msal.PublicClientApplication(client_id, authority=authority, token_cache=cache)
+accounts = app.get_accounts()
+
+if accounts:
+    token_response = app.acquire_token_silent(scopes, account=accounts[0])
+else:
+    flow = app.initiate_device_flow(scopes=scopes)
+    if 'user_code' not in flow:
+        raise Exception("Failed to create device flow")
+    print(flow['message'])
+    token_response = app.acquire_token_by_device_flow(flow)
 
 if 'access_token' not in token_response:
     raise Exception("Failed to acquire token")
 
+# Save token cache
+with open(cache_file, 'w') as f:
+    f.write(cache.serialize())
+
 access_token = token_response['access_token']
 
 # Fetch events with pagination and expand recurring events
 headers = {'Authorization': f'Bearer {access_token}'}
 events_url = 'https://graph.microsoft.com/v1.0/me/events?$top=100&$expand=instances'
 events = []
-
+print("Fetching events...")
 while events_url:
     response = requests.get(events_url, headers=headers)
     response_data = response.json()
     events.extend(response_data.get('value', []))
+    print(f"Fetched {len(events)} events so far...", end='\r')
     events_url = response_data.get('@odata.nextLink')
 
 # Save events to a file in iCalendar format
-with open('outlook_events.ics', 'w') as f:
+output_file = f'output_ics/outlook_events_latest.ics'
+print(f"Saving events to {output_file}...")
+with open(output_file, 'w') as f:
     f.write("BEGIN:VCALENDAR\nVERSION:2.0\n")
     for event in events:
         if 'start' in event and 'end' in event:
@@ -49,5 +69,21 @@ with open('outlook_events.ics', 'w') as f:
             f.write(f"BEGIN:VEVENT\nSUMMARY:{event['subject']}\n")
             f.write(f"DTSTART:{start.strftime('%Y%m%dT%H%M%S')}\n")
             f.write(f"DTEND:{end.strftime('%Y%m%dT%H%M%S')}\n")
+            if 'recurrence' in event and event['recurrence']:  # Check if 'recurrence' exists and is not None
+                for rule in event['recurrence']:
+                    if rule.startswith('RRULE'):
+                        rule_parts = rule.split(';')
+                        new_rule_parts = []
+                        for part in rule_parts:
+                            if part.startswith('UNTIL='):
+                                until_value = part.split('=')[1]
+                                until_date = parser.isoparse(until_value)
+                                if start.tzinfo is not None and until_date.tzinfo is None:
+                                    until_date = until_date.replace(tzinfo=UTC)
+                                new_rule_parts.append(f"UNTIL={until_date.strftime('%Y%m%dT%H%M%SZ')}")
+                            else:
+                                new_rule_parts.append(part)
+                        rule = ';'.join(new_rule_parts)
+                    f.write(f"{rule}\n")
             f.write("END:VEVENT\n")
     f.write("END:VCALENDAR\n")