NonReserved can only contain tokens. Found nested rule: – How to solve this Elasticsearch error

Opster Team

July-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” nonReserved can only contain tokens. Found nested rule: ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: parser and plugin.

Log Context

Log “nonReserved can only contain tokens. Found nested rule:”classname  is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 public void exitNonReserved(SqlBaseParser.NonReservedContext context) {
 // tree cannot be modified during rule enter/exit _unless_ it's a terminal node
 if (!(context.getChild(0) instanceof TerminalNode)) {
 int rule = ((ParserRuleContext) context.getChild(0)).getRuleIndex();
 throw new ParsingException("nonReserved can only contain tokens. Found nested rule: " + ruleNames.get(rule));
 // replace nonReserved words with IDENT tokens


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