title: Grails validation error from service method
body: <p>I have a method in a service class that creates an object:</p>
  
  <pre><code>def createContent (fileName, description) {
  
      def content = new Content(
          fileName:fileName,
          description:description,
      ).save()
  }
  </code></pre>
  
  <p>Neither of those properties are nullable.  How can I pass the validation errors back to be displayed?  I've tried flash.message and render, both of which don't work from within service classes.  I also tried
      .save(failOnError:true)
  which displayed a long list of errors.</p>