>> Provide custom attributes while deploying a service allowing end user to use contextualizaion (like in vms mode)
Could you elaborate more on this?
>> When a service is deployed, vm have this name format : frontend_0_(service1)
I would like to permit the user to set whatever he wants as vm name
This is not supported, you can define the name format in :vm_name_template attribute at /etc/one/oneflow-server.conf`. You can find more info here: http://docs.opennebula.org/5.8/advanced_components/application_flow_and_auto-scaling/appflow_configure.html#configuration