message: Handle errors fetching gauge data. Show a ? instead of the previous graph state.
diff: @@ -112,7 +112,15 @@ export class Gauge extends BaseGraph {
  }];
  }
  - updateGraph (data) {
  + updateGraph (data, err) {
  + if (err) {
  + this.data[0].marker.colors[1] = colors.gray;
  + this.data[0].values[1] = 0;
  + this.data[0].values[2] = 1;
  + this.layout.annotations[0].text = '?';
  + relayout(this.node, this.layout);
  + return;
  + }
  data = parseInt(_.get(data, '[0].data.result[0].value[1]'), 10);
  if (isNaN(data)) {
  // eslint-disable-next-line no-console
  