Bridge a port that is exposed inside a container to your host

docker-intercept.sh

#!/bin/bash
# Call as docker-intercept <container-name> <port-inside-container> <port-on-host>
set -e
container="$1"
container_port="$2"
host_port="$3"

network_id="$(docker inspect "$container" | jq '.[0].NetworkSettings.Networks | to_entries | .[0].value.NetworkID' -r)"
container_ip="$(docker inspect "$container" | jq '.[0].NetworkSettings.Networks | to_entries | .[0].value.IPAddress' -r)"

docker run -ti --rm --net "$network_id" -p "$host_port:$host_port" bobrik/socat "TCP4-LISTEN:$host_port,fork,bind=0.0.0.0" "TCP4:$container_ip:$container_port"