docker.md

whenever I visit container-ip:8000 or http://localhost:8000, it doesn't work

See docker/issues/4007: you would need to use port forwarding when using boot2docker on OSX.
That means the VM boot2docker needs to forward the port 8000 to the OSX actual host.
I mentioned it here:

$ VBoxManage modifyvm "boot2docker-vm" --natpf1 "tcp-port8000,tcp,,8000,,8000";

If the vm is already running, you should run this other command:

$ VBoxManage controlvm "boot2docker-vm" natpf1 "tcp-port8000,tcp,,8000,,8000";

This script, for example, can help.

As shown in "Boot2docker on OsX", localhost wouldn't work:

The reason it doesn’t work is your DOCKER_HOST address is not the localhost address (0.0.0.0) but is instead the address of the boot2docker VM.

Get the address of the boot2docker VM.

$ boot2docker ip
192.168.59.103

Enter the http://192.168.59.103:8000 address in your browser.