As of 2018-03-30.
Here is a blog post:
https://dev.to/bufferings/access-host-from-a-docker-container-4099
Prepare a target.
# Start nginx as a target running on host
docker run -p 8888:80 --rm nginx
# You can see 8888 working on the host
curl localhost:8888
Let's access it from a container.
# Build
docker build -t docker-access-host:demo .
# Run. You should be able to see nginx result & hosts file
docker run --rm docker-access-host:demo
# It has host.docker.internal only when the host is Linux