code: @GetMapping(value = "/{entityTypeId}", produces = APPLICATION_JSON_VALUE)
    public EntityCollectionResponse retrieveEntityCollection(
        @PathVariable("entityTypeId") String entityTypeId,
        @Valid EntityCollectionRequest request,
        @RequestParam(value = "attributes", required = false) String[] attributes,
        @RequestParam(value = "expand", required = false) String[] attributeExpands) {
      Set<String> attributesSet = toAttributeSet(attributes);
      Map<String, Set<String>> attributeExpandSet = toExpandMap(attributeExpands);
  
      return retrieveEntityCollectionInternal(
          entityTypeId, request, attributesSet, attributeExpandSet);
    }
docs: Do a query
  
  <p>Returns json