[tasks] Add oauth flow for Todoist

vrobbler/apps/tasks/todoist.py

@@ -0,0 +1,61 @@
+import logging
+
+import secrets
+
+import requests
+from django.conf import settings
+from django.contrib.auth import get_user_model
+from profiles.models import UserProfile
+
+from vrobbler.settings import TODOIST_CLIENT_ID
+
+logger = logging.getLogger(__name__)
+User = get_user_model()
+
+TODOIST_OAUTH_START_URL = "https://todoist.com/oauth/authorize?client_id={id}&scope=data:read_write&state=".format(
+    id=TODOIST_CLIENT_ID
+)
+TODOIST_OAUTH_TOKEN_URL = "https://todoist.com/oauth/access_token"
+
+
+def generate_todoist_oauth_url(user_id: int) -> str:
+    user_profile = User.objects.filter(id=user_id).first().profile
+    user_profile.todoist_state = secrets.token_hex(16)
+    user_profile.save(update_fields=["todoist_state"])
+    return TODOIST_OAUTH_START_URL + user_profile.todoist_state
+
+
+def get_todoist_access_token(user_id: int, state: str, code: str):
+    logger.info(
+        "[get_todoist_access_token] called",
+        extra={"state": state, "code": code},
+    )
+    user_profile = UserProfile.objects.filter(user_id=user_id).first()
+
+    if not user_profile:
+        raise Exception
+
+    if user_profile.todoist_state != state:
+        logger.info(
+            "[get_todoist_access_token] state mismatch",
+            extra={"user_id": user_id, "state": state},
+        )
+        raise Exception
+
+    post_data = {
+        "client_id": settings.TODOIST_CLIENT_ID,
+        "client_secret": settings.TODOIST_CLIENT_SECRET,
+        "code": code,
+    }
+
+    response = requests.post(TODOIST_OAUTH_TOKEN_URL, data=post_data)
+
+    if response.status_code == 200:
+        user_profile.todoist_auth_key = response.json().get("access_token")
+        user_profile.todoist_state = None
+        user_profile.save()
+
+    logger.info(
+        "[get_todoist_access_token] finished",
+        extra={"user_id": user_profile.user.id},
+    )