mORMot Open Source

spanfkyous

Member

Registered: 2025-06-04

Posts: 4

THttpClientSocket and fiddler

How should THttpClientSocket be configured to support a Fiddler Classic proxy?

For a standard HTTP proxy, the following configuration works correctly:

THttpClientSocket.Tunnel.From('http://proxyserver:port');

With this setup, both HTTP and HTTPS requests go through the proxy without issues.

However, when using Fiddler Classic as the proxy (e.g., http://127.0.0.1:8888), the same configuration only works for HTTP websites. HTTPS requests fail to connect through the proxy. The proxy is still set using:

THttpClientSocket.Tunnel.From('http://127.0.0.1:8888');

fiddler classic: https://www.telerik.com/fiddler/fiddler-classic , fiddler was run with decrypt ssl option active.
active SSL decryption from here: tools->options->HTTPS->Capture Https /Decrypt Https SSL