I was curious to trying out the various methods mentioned above so I made a deb-signal template only to find out none seem to work:
wget:
$ export https_proxy=http://127.0.0.1:8082
$ wget -O- https://updates.signal.org/desktop/apt/keys.asc
Connecting to 127.0.0.1:8082... connected.
Proxy tunneling failed: CONNECT denied (ask the admin to allow HTTPS tunnels)Unable to establish SSL connection.
curl:
$ curl --proxy http://127.0.0.1:8082/ --tlsv1.2 --proto =https --max-time 180 "https://updates.signal.org/desktop/apt/keys.asc"
curl: (56) Received HTTP code 403 from proxy after CONNECT
I then noticed that when launching the command, my apt-cacher qube was started and I found the following command to be working:
curl --proxy http://127.0.0.1:8082/ --tlsv1.2 --max-time 180 "http://HTTPS///updates.signal.org/desktop/apt/keys.asc"
So I had to remove --proto =https and change https:// to http://HTTPS///.
Is this behavior to be expected when not dealing with repositories but an apt-cacher qube is enabled?