init(base_url: String) do
		self.base_url = base_url
		var root = service_root
		assert root isa JsonObject else
			sys.stderr.write "Neo4jClientError: cannot connect to server at <{base_url}>.\n"
		end
		self.node_url = root["node"].to_s
		self.batch_url = root["batch"].to_s
		self.cypher_url = root["cypher"].to_s
	end