OpenNebula have bindings for Ruby, Python, Java and Golang but not for node.js. Here (System Interfaces — OpenNebula 5.8.5 documentation) you can find more information about the supported APIs and some examples.
If you want to use node.js with OpenNebula you have to find a node.js XMLRPC library and make the calls by yourself. The XMLRPC calls format is available here: XML-RPC API — OpenNebula 5.8.5 documentation
But do you think, in a close futur, we will be able to get official binding for nodejs supported for opennebula ? I don’t know if you are from the team opennebula.
Do you have some idea to help me to build a web app base on the API XML-RPC for Opennebula. Such as good language and framework ?