When you use Disqus API on the server side, you have to put 'app_secret' in URLs on every API request. Here is what Disqus doc says:
If you are using the server-side API, you will need to send api_secret with your secret API key value.
(https://disqus.com/api/docs/requests/)
When I call URL like this:
https://disqus.com/api/3.0/threads/list.json?access_token={ACCESS_TOKEN}
I get this error:
{"code":5,"response":"Invalid API key"}
When change URL to this:
https://disqus.com/api/3.0/threads/list.json?access_token={ACCESS_TOKEN}&api_secret={API_SECRET}
It works ok.
I think it is very, very dangerous to use secret key in common GET requests. I don't know any other API that would be required to use secret key in GET requests.
What do you think about it?