title: Varying responses whilst posting to pages
body: <p>I have an app whose part of functionality is posting to clients' Facebook pages on their behalf. Clients authorise the app, I generate extended user access tokens and page access tokens and post to their pages as necessary. Everything has been fine until recently. The app posted to a client's page without causing a nuisance, only the photo post has never appeared on their timeline.</p>
  
  <p>I reproduced, compared and narrowed down the faulty behaviour, but I have no idea how to fix it. When I post a photo to Facebook using the following function:</p>
  
  <pre><code>def post_photo(graph_api, post, post_message, target_page, **kwargs):
      """Posts a photo to wall."""
      img_fp = urlopen(post['image'])
      if img_fp.getcode() != 200:
          raise ValueError('Image request failed. Returned code: %s' % img_fp.getcode())
  
      return graph_api.put_photo(img_fp, post_message, profile_id=target_page, **kwargs)
  </code></pre>
  
  <p>the response usually (always?) contains two values: <code>id</code> and <code>post_id</code>, while <code>post_id</code> was missing in the response of the post that never appeared.</p>
  
  <p>Is there anything that needs to be changed in page's or app's settings (different Facebook apps post to different pages)? Privacy settings, extra permissions, anything? I've run out of ideas. Access token debugger doesn't show anything exceptional, neither do page settings.</p>