rollbackFunctionUpgradeTraffic method
      
Future<Operation> 
rollbackFunctionUpgradeTraffic(
    
- RollbackFunctionUpgradeTrafficRequest request,
- String name, {
- String? $fields,
Reverts the traffic target of a function from the 2nd Gen copy to the original 1st Gen function.
After this operation, all new traffic would be served by the 1st Gen.
request - The metadata request object.
Request parameters:
name - Required. The name of the function for which traffic target
should be changed back to 1st Gen from 2nd Gen.
Value must have pattern
^projects/\[^/\]+/locations/\[^/\]+/functions/\[^/\]+$.
$fields - Selector specifying which fields to include in a partial
response.
Completes with a Operation.
Completes with a commons.ApiRequestError if the API endpoint returned an error.
If the used http.Client completes with an error when making a REST call,
this method will complete with the same error.
Implementation
async.Future<Operation> rollbackFunctionUpgradeTraffic(
  RollbackFunctionUpgradeTrafficRequest request,
  core.String name, {
  core.String? $fields,
}) async {
  final body_ = convert.json.encode(request);
  final queryParams_ = <core.String, core.List<core.String>>{
    if ($fields != null) 'fields': [$fields],
  };
  final url_ = 'v2/' +
      core.Uri.encodeFull('$name') +
      ':rollbackFunctionUpgradeTraffic';
  final response_ = await _requester.request(
    url_,
    'POST',
    body: body_,
    queryParams: queryParams_,
  );
  return Operation.fromJson(response_ as core.Map<core.String, core.dynamic>);
}