Fiddler classic extension unable to recognize 502 response (DNS Lookup Failed)

[Ben]

Hello,

For the extension I work on it might happen that I need to recognize a HTTP request to a domain that does not exist. However if such a session ends with "HTTP/1.1 502 Fiddler - DNS Lookup Failed" in the Response Header, my extension is not triggered.

Such responses neither trigger the

AutoTamperResponseBefore(Session oSession)

method, nor the

OnPeekAtResponseHeaders(Session oSession)

method. My question is, what can I do here to notice such cases with my extension?

And another question, which other cases should I be aware of that don't cause a proper response?

[Nick Iliev]

If the domain is not existing, you should not be able to receive an HTTP response as you won't be able to connect to the HTTP server in the first place. So that said, it is expected that you are not able to receive info in the mentioned methods.