clh: Add Generation tools for API client

cloud-hypervisor provides an API server to send commands
in a qmp and Firecracker style over an Unix socket.

The API is defined via OpenAPI, this commit adds
scripts to help to generate a client using:

https://github.com/OpenAPITools/openapi-generator

This will make easy to update any change related with the API
in the future.

Signed-off-by: Jose Carlos Venegas Munoz <jose.carlos.venegas.munoz@intel.com>

virtcontainers/README.md

@@ -79,6 +79,10 @@ The `virtcontainers` package relies on hypervisors to start and stop virtual mac
 sandboxes will be running. An hypervisor is defined by an Hypervisor interface implementation,
 and the default implementation is the QEMU one.
 
+### Update cloud-hypervisor client code
+
+See [docs](pkg/cloud-hypervisor/README.md)
+
 ## Agents
 
 During the lifecycle of a container, the runtime running on the host needs to interact with

virtcontainers/pkg/cloud-hypervisor/Makefile

@@ -0,0 +1,21 @@
+#
+# Copyright (c) 2019 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+all: | update-yaml generate-client-code
+
+generate-client-code: clean-generated-code
+	docker run --rm \
+		--user $$(id -u):$$(id -g) \
+		-v $${PWD}:/local openapitools/openapi-generator-cli generate \
+		-i /local/cloud-hypervisor.yaml \
+		-g go \
+		-o /local/client
+
+update-yaml:
+	curl -OL https://raw.githubusercontent.com/cloud-hypervisor/cloud-hypervisor/master/vmm/src/api/openapi/cloud-hypervisor.yaml
+
+clean-generated-code:
+	rm "./client" -rf

virtcontainers/pkg/cloud-hypervisor/README.md

@@ -0,0 +1,13 @@
+# Cloud Hypervisor OpenAPI generated code
+
+This directory provide tools to generate code client based
+on `cloud-hypervisor` `OpenAPI` schema.
+
+## Update client to match latest Cloud Hypervisor server API
+
+Requirements:
+ - docker: `openapi-generator` is executed in a docker container
+
+```
+make all
+```