Malformed regular expression file should continue with array after object – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-8.9

Before you dig into reading this guide, have you tried asking OpsGPT what this log means? You’ll receive a customized analysis of your log.

Try OpsGPT now for step-by-step guidance and tailored insights into your Elasticsearch operation.

Briefly, this error occurs when Elasticsearch encounters a malformed regular expression file. This typically happens when the JSON structure of the file is incorrect, specifically when an ‘object’ is followed by something other than an ‘array’. To resolve this issue, you should review the JSON file for any syntax errors. Ensure that every ‘object’ is followed by an ‘array’ as expected. You may also use a JSON validator tool to check the structure of your file. Additionally, ensure that your Elasticsearch version supports the regular expression used in your file.

For a complete solution to your to your search operation, try for free AutoOps for Elasticsearch & OpenSearch . With AutoOps and Opster’s proactive support, you don’t have to worry about your search operation – we take charge of it. Get improved performance & stability with less hardware.

This guide will help you check for common problems that cause the log ” malformed regular expression file; should continue with ‘array’ after ‘object’ ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: .

Log Context

Log “malformed regular expression file; should continue with ‘array’ after ‘object'” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 static List> readParserConfigurations(XContentParser yamlParser) throws IOException {
 List> patternList = new ArrayList<>();  XContentParser.Token token = yamlParser.nextToken();
 if (token != XContentParser.Token.START_ARRAY) {
 throw new ElasticsearchParseException("malformed regular expression file; should continue with 'array' after 'object'");
 }  token = yamlParser.nextToken();
 if (token != XContentParser.Token.START_OBJECT) {
 throw new ElasticsearchParseException("malformed regular expression file; expecting 'object'");


How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Get expert answers on Elasticsearch/OpenSearch