Google CardDav同步遇“Insufficient Permission”权限问题求助

Hey Alex, since you’ve already got Google CalDAV sync working via OAuth2, let’s tackle that frustrating "Insufficient Permission" error you’re hitting with CardDAV. Here’s a step-by-step breakdown of the most likely fixes:

CalDAV and CardDAV rely on distinct required scopes—just because your CalDAV scopes are valid doesn’t mean they cover CardDAV.

• You must include the https://www.googleapis.com/auth/carddav scope in your OAuth authorization request, alongside any CalDAV scopes you’re already using.
• Head to your Google Cloud Console’s OAuth consent screen and confirm this scope is listed. If you’ve added it recently, you might need to re-submit the consent screen for verification if you’re serving external users (non-internal to your organization).

Old access/refresh tokens won’t pick up new scopes automatically, so let’s reset that:

• Go to the authenticated user’s Google Account > Security > Third-party apps with account access, find your app, and revoke its access.
• Re-authorize your app from scratch. Make sure the carddav scope is explicitly presented during the auth flow—this ensures the new tokens include the necessary permissions.

Even with correct scopes, a misconfigured request can trigger permission errors:

• Use the official CardDAV endpoint: https://www.googleapis.com/carddav/v1/principals/{userEmail}/lists/default (replace {userEmail} with the authenticated user’s email).
• Confirm your requests include the valid OAuth2 token in the Authorization header as Bearer {accessToken}. You can inspect the token’s claims (to verify the carddav scope is present) using a tool like jwt.io.

CalDAV and CardDAV are separate APIs—don’t assume enabling one enables the other:

• In your Google Cloud Project, go to APIs & Services > Library, search for "CardDAV API", and enable it if it’s not already active.
• Double-check your OAuth client ID configuration matches your app type (web, desktop, mobile) and there are no unintended restrictions blocking CardDAV requests.

Isolate the issue by running a simple PROPFIND request to the CardDAV endpoint:

curl -X PROPFIND -H "Authorization: Bearer YOUR_ACCESS_TOKEN" -H "Content-Type: application/xml" -d '<?xml version="1.0" encoding="UTF-8"?>
<D:propfind xmlns:D="DAV:">
  <D:prop>
    <D:displayname/>
  </D:prop>
</D:propfind>' https://www.googleapis.com/carddav/v1/principals/user@example.com/lists/default

If this returns the same permission error, the problem is almost certainly with your scopes or token. If it works, the issue lies in your app’s request implementation.

内容的提问来源于stack exchange，提问作者Alex