Unexpected token token expected - Common causes and quick fixes

Unexpected token token expected – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-8.9

Briefly, this error occurs when Elasticsearch encounters an unexpected token in the JSON request body. This usually happens due to a syntax error, such as a missing or misplaced bracket, comma, or quotation mark. To resolve this issue, you should carefully review your JSON request body for any syntax errors. Make sure that all brackets, commas, and quotation marks are correctly placed. Also, ensure that all objects and arrays are properly closed. Using a JSON validator can help identify and correct these errors.

This guide will help you check for common problems that cause the log ” unexpected token [” + token + “]; expected [{; ] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: .

Log Context

Log “unexpected token [” + token + “]; expected [{; ]” class name is StoredScriptSource.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 token = parser.nextToken();  if (token == Token.START_OBJECT) {
 return PARSER.apply(parser; null).build(false);
 } else {
 throw new ParsingException(parser.getTokenLocation(); "unexpected token [" + token + "]; expected [{; ]");
 }
 } else {
 throw new ParsingException(
 parser.getTokenLocation();
 "unexpected field [" + name + "]; expected [" + SCRIPT_PARSE_FIELD.getPreferredName() + "]"