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Forum Discussion
straightvisions
8 years agoNew member | Level 2
[PHP] /files/list_folder returns Curl Error 51
Related SDK and Issue:
https://github.com/kunalvarma05/dropbox-php-sdk/issues/100
Warning: cURL error 51: SSL: no alternative certificate subject name matches target host name 'api.dropboxapi.com' (see http://curl.haxx.se/libcurl/c/libcurl-errors.html)
Test Script
$ch = curl_init(); curl_setopt($ch, CURLOPT_URL, "https://api.dropboxapi.com/2/files/list_folder"); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_CAINFO, "cacert.pem"); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0); curl_setopt($ch, CURLOPT_POSTFIELDS, "{\"path\":\"\"}"); curl_setopt($ch, CURLOPT_POST, 1); $headers = array(); $headers[] = "Authorization: Bearer <TOKEN>"; $headers[] = "Content-Type: application/json"; curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); $result = curl_exec($ch); if (curl_errno($ch)) { echo 'Error:' . curl_error($ch); } curl_close ($ch); var_dump($result);
When I use api.dropbox.com, /files/list_folder works, but not /files/download:
Incorrect host for API function files/download. You must issue the request to content.dropboxapi.com
Needless to say that content.dropbox.com isn't available in v2.
- Greg-DB
Dropbox Staff
The api.dropboxapi.com host is currently being served with a valid certificate, so it's not clear why your client isn't trusting it. (Is there any security software, e.g., firewall, or a proxy that may be intefering?)
In any case, the /2/files/list_folder endpoint does need to be called on the Dropbox API servers, for which either of these host names are valid:
- api.dropbox.com
- api.dropboxapi.com
The /2/files/download endpoint does need to be called on the Dropbox API content servers, for which either of these host names are valid:
- api-content.dropbox.com
- content.dropboxapi.com
(Note that at the end of your post you mentioned "content.dropbox.com isn't available in v2". That is true in that "content.dropbox.com" is not a valid host name, but "content.dropboxapi.com" is valid and does serve API v2.)
- straightvisionsNew member | Level 2
Thank you for your detailed answer. Based on this, I was able to track down the bug, which was indeed a wrong content url.
Thank you, issue solved.
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