Implement basic authentication and calendar list acquisition

bulk_reminders/api.py

@@ -0,0 +1,86 @@
+from __future__ import print_function
+
+import datetime
+import os.path
+import traceback
+from typing import Any, Iterator, List, Optional, Tuple
+
+from google.auth.transport.requests import Request
+from google.oauth2.credentials import Credentials
+from google_auth_oauthlib.flow import InstalledAppFlow
+from googleapiclient.discovery import Resource, build
+
+# If modifying these scopes, delete the file token.json.
+SCOPES = ['https://www.googleapis.com/auth/calendar']
+
+
+class Calendar(object):
+    def __init__(self) -> None:
+        self.credentials: Optional[Credentials] = None
+        self.service: Optional[Resource] = None
+
+    def save_token(self) -> None:
+        """Store the credentials for later use."""
+        with open('token.json', 'w') as token:
+            token.write(self.credentials.to_json())
+
+    def authenticate_via_token(self) -> bool:
+        """Attempt to login using the tokens stored in token.json"""
+        if os.path.exists('token.json'):
+            self.credentials = Credentials.from_authorized_user_file('token.json', SCOPES)
+            if self.credentials and self.credentials.expired and self.credentials.refresh_token:
+                try:
+                    self.credentials.refresh(Request())
+                except BaseException as e:
+                    traceback.print_exc()
+                    return False
+                self.save_token()
+            return True
+        return False
+
+    def authenticate_via_oauth(self) -> bool:
+        """Attempt to acquire credentials"""
+        try:
+            flow = InstalledAppFlow.from_client_secrets_file(
+                    'credentials.json', SCOPES)
+            self.credentials = flow.run_local_server(port=0)
+            self.save_token()
+        except BaseException as e:
+            traceback.print_exc()
+            return False
+
+    def setupService(self) -> None:
+        """Setup the Google App Engine API Service for the Calendar API"""
+        self.service = build('calendar', 'v3', credentials=self.credentials)
+
+    def getCalendars(self) -> Iterator[Any]:
+        """Retrieve all calendar data"""
+        page_token = None
+        while True:
+            calendar_list = self.service.calendarList().list(pageToken=page_token, minAccessRole='writer').execute()
+            for entry in calendar_list['items']:
+                # Referencing the primary calendar should be done with the ID 'primary'
+                if entry.get('primary', False):
+                    entry['id'] = 'primary'
+                yield entry
+
+            # Continue loading more calendars
+            page_token = calendar_list.get('nextPageToken')
+            if page_token is None:
+                break
+
+    def getEvents(self, calendarID: str) -> None:
+        now = datetime.datetime.utcnow().isoformat() + 'Z'  # 'Z' indicates UTC time
+        events_result = self.service.events().list(calendarId=calendarID, timeMin=now,
+                                                   maxResults=10, singleEvents=True,
+                                                   orderBy='startTime').execute()
+        events = events_result.get('items', [])
+
+    def getCalendarsSimplified(self) -> List[Tuple[str, str]]:
+        """Extracts the bare minimum required information from the Calendar."""
+        return [(calendar['id'], calendar['summary']) for calendar in self.getCalendars()]
+
+
+class Event():
+    def __init__(self, title, date, time):
+        pass