feat: Add the apiVersion protected property to the generated resource…

…s when applicable

generator/src/googleapis/codegen/api.py

@@ -577,6 +577,13 @@ def __init__(self, api, name, def_dict, parent=None):
     method_dict = self.values.get('methods') or {}
     for name in sorted(method_dict):
       method = Method(api, name, method_dict[name], parent=self)
+
+      # Support for the new API versioning on the discovery document
+      # the design states that all the methods should have the same version
+      # hence why we take it the first time and set it once
+      if not self.get('apiVersion') and 'apiVersion' in method_dict[name]:
+        self.SetTemplateValue('apiVersion', method_dict[name]['apiVersion'])
+
       requestType = method.values.get('requestType')
       if requestType and requestType.GetTemplateValue('className') and \
          requestType.GetTemplateValue('className') not in self._method_classes:

generator/src/googleapis/codegen/languages/php/default/templates/___api_className___/Resource/___resources_className___.php.tmpl

@@ -14,7 +14,9 @@ namespace {{ api.ownerName }}\Service\{{ api.className }}\Resource;
  *  </code>
  */
 class {{ resource.className }} extends \Google\Service\Resource
-{{% indent %}{% for method in resource.methods %}
+{{% indent %}{% if resource.apiVersion %}
+protected $apiVersion = '{{ resource.apiVersion }}';
+{% endif %}{% for method in resource.methods %}
 {% call_template _method method=method %}{% endfor %}
 {% endindent %}}