Briefly, this error occurs when Elasticsearch expects a certain field in the request body, but it’s not provided. This could be due to a typo in the field name or the field is completely missing from the request. To resolve this, ensure that the field name in your request matches exactly with the field name expected by Elasticsearch. Also, check that the field is not missing from your request. If the field is optional and you don’t want to provide it, ensure that your request is correctly formatted without it.
This guide will help you check for common problems that cause the log ” expected field [ ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: percolator.
Log Context
Log “expected field [” class name is PercolateQueryBuilder.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
if (fieldType == null) {
throw new QueryShardException(context; "field [" + field + "] does not exist");
} if ((fieldType instanceof PercolatorFieldMapper.PercolatorFieldType) == false) {
throw new QueryShardException(context; "expected field [" + field +
"] to be of type [percolator]; but is of type [" + fieldType.typeName() + "]");
} final List docs = new ArrayList<>();
String type = context.getType();
