We recently announced that the Flickr API is going SSL-only.
To support this move, we have also restricted the Flickr YQL tables to be available over SSL-only.
All developers using the Flickr YQL tables will need to make the following updates to their API settings by June 24, 2014:
The domain name query.yahooapis.com will remain the same.
As of June 24, 2014, we will limit all access to Flickr YQL tables to secure SSL connections only. No Flickr API data will be accessible over HTTP from this date onwards. If you don’t switch the access protocol to HTTPS, your users will not be able to access Flickr data via your service.
Thank you for supporting us and our users in making the shift to HTTPS.
You go to the Flickr Developer Guide for more information.