Exception while fetching data (/getRecords/nestedRecords) : Cannot invoke "java.util.Map.get(Object)" because "map" is null:
java.lang.NullPointerException: Cannot invoke "java.util.Map.get(Object)" because "map" is null
    at org.dataloader.DataLoaderHelper.lambda$invokeMapBatchLoader$11(DataLoaderHelper.java:429)
    at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:642)
    at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
    at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1769)
    at org.springframework.cloud.sleuth.instrument.async.TraceRunnable.run(TraceRunnable.java:63)
    at org.springframework.security.concurrent.DelegatingSecurityContextRunnable.run(DelegatingSecurityContextRunnable.java:82)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)
    at com.blah.graphql.async.DecoratedThread.run(DecoratedThread.java:51)

private DataLoader<UUID, List<NestedRecord>> createNestedRecordDataLoader() {
    MappedBatchLoader<UUID, List<NestedRecord>> nestedRecordBatchLoader =
        (Set<UUID> parentIds) -> CompletableFuture.supplyAsync(
                () -> nestedRecordService.getNestedRecordsByParentIds(
                    parentIds), graphqlAsyncTaskExecutor)
            .orTimeout(threadTimeoutSeconds, TimeUnit.SECONDS)
            .exceptionally(e -> {
              log.error("Exception while fetching NestedRecords: {}", e);
              return null;
            });

    return DataLoaderFactory.newMappedDataLoader(
        nestedRecordBatchLoader );
  }