allow for null entities

Author: dbuezas

src/cache/Cache.ts

@@ -182,6 +182,7 @@ export default class Cache {
           // Making these fetches sequentially ensures that the already fetched ranges of each
           // request are not fetched more than once
           for (const entity of entityGroup) {
+            if (!entity.entity) continue;
             const entityKey = getEntityKey(entity);
             this.ranges[entityKey] ??= [];
             const offsetRange = [

src/types.ts

@@ -21,7 +21,7 @@ export type InputConfig = {
   title?: string;
   offset?: TimeDurationStr;
   entities: ({
-    entity: string;
+    entity?: string;
     attribute?: string;
     statistic?: StatisticType;
     period?: StatisticPeriod | "auto" | AutoPeriodConfig;