Nova provides the ability to create access_urls through the os-consoles extension. Support for accessing this URL is provided by novaclient:
$ nova get-vnc-console[server_id][novnc|xvpvnc]
Specify 'novnc' to retrieve a URL suitable for pasting
into a web browser. Specify 'xvpvnc' for a URL suitable for
pasting into the Java client.
So to request a web browser URL:
$ nova get-vnc-console [server_id] novnc
