/**
  * Check that the project field is not empty and is a valid project.
  *
  * @param project The name of the project.
  * @return Ok if not empty, error otherwise.
  */
 public FormValidation doCheckProject(@QueryParameter String project) {
   setGlobalConfiguration();
   project = project.trim();
   OctopusValidator validator = new OctopusValidator(api);
   return validator.validateProject(project);
 }