Meta must be an object got – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 7.6-7.15

Briefly, this error occurs when Elasticsearch expects a metadata object but receives a different data type. Metadata in Elasticsearch should be structured as an object, but if it’s incorrectly formatted as a string, number, or array, this error will occur. To resolve this, ensure that the metadata is correctly formatted as an object. Also, check your data input or mapping configurations to ensure they are correctly set up. If you’re using a script or application to input data, ensure it’s correctly formatting the metadata as an object.

This guide will help you check for common problems that cause the log ” [meta] must be an object; got ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index.

Log Context

Log “[meta] must be an object; got” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 * Parse the {@code meta} key of the mapping.
 public static Map parseMeta(String name; Object metaObject) {
 if (metaObject instanceof Map == false) {
 throw new MapperParsingException("[meta] must be an object; got " + metaObject.getClass().getSimpleName() +
 "[" + metaObject + "] for field [" + name + "]");
 Map meta = (Map) metaObject;
 if (meta.size() > 5) {