Linux

Requires using its custom certificate authority. Nice for scraping without root access, but it won't work for all programs. Openssl injection/ebpf is more flexible, but I'm not sure if there's a tool that can do that.

When you run httptap -- , httptap runs in an isolated network namespace, injecting a certificate authority created on-the-fly in order to decrypt HTTPS traffic. Here is the process in detail:

In linux, there is a kernel API for creating and configuring network interfaces. Conventionally, a network interface would be a physical ethernet or WiFi controller in your computer, but it is possible to create a special kind of network interface called a TUN device. A TUN device shows up to the system in the way that any network interface shows up, but any traffic written to it will be delivered to a file descriptor held by the process that created it. Httptap creates a TUN device and runs the subprocess in an environment in which all network traffic is routed through that device.

If you want a more comprehensive overview of your traffic and the ability to set firewall rules to block specific sites, I found Safing Portmaster to be a great option.

You also get filter lists, ability to tweak connections made by different apps, and, as a paid option, connect to a Tor-like network where every app van be designated its own exit node, at the speed of about 60mbits/s last time I checked (currently not using this option).

Sounds very handy!

Thanks for sharing. On Windows I always liked Fiddler for this. But I haven't found a decent alternative yet.