Facebook API 04-05-2018异常求助：访问Group节点不存在的members字段

Hey there, let's work through this error you're hitting with the Facebook Graph API v2018-04-05. That error message is pretty clear on the surface, but the root cause ties directly to Facebook's API permission changes around that version. Here's what you need to know and do to fix it:

Why This Happens #

Starting with the v2018-04-05 (Graph API v3.0) release, Facebook restricted access to the members field on Group nodes. This field is no longer accessible by default—you need specific, approved permissions to retrieve group member data, and even then, access is limited to certain use cases.

Step-by-Step Fixes #

• Check Required Permissions: To access the members field, your app must have the groups_access_member_info permission. This isn't a standard permission you can just toggle on; it requires submitting your app for Facebook's review, and approval is only granted for apps that fit specific use cases (like community management tools built to help group admins).
• Verify Access Token Scope: Make sure the access token you're using was generated with the correct permission scope. If you're using a user access token, the user must be a member of the group (ideally an admin) and have granted the necessary permissions to your app. Note that older permissions like user_groups were deprecated before this API version, so they won't work here.
• Confirm Group Admin Status: Even with the right permissions, non-admin users (or apps not added as group admins) can't retrieve member data. If you're testing with a personal account, ensure you're an admin of the group you're querying. If your app needs access to non-admin groups, you'll need to meet stricter review criteria.
• Validate Your Request Format: Double-check that your API call is structured correctly. The proper endpoint is:

  GET /{group-id}/members?access_token={your-valid-access-token}
  

  Typos in the field name (like misspelling "members") can also trigger this error, so confirm that's not the case.

Alternative Workarounds #

If you can't get approval for groups_access_member_info, consider if your use case can adapt to Facebook's current limitations:

• For public groups, you might still be able to retrieve basic member counts using the member_count field (this doesn't require special permissions).
• If you're building a tool for group admins, emphasize that use case in your permission review request—Facebook is more likely to approve apps that help admins manage their communities.

内容的提问来源于stack exchange，提问作者Kim Tỏa Tỏa