版本： 6.8-7.15
简而言之，当Elasticsearch在规则表达式中期望某种数据类型（对象），但却遇到了不同的数据类型时，就会发生此错误。这种不匹配会导致解析失败。要解决此问题，您应该检查规则表达式中输入的数据类型。确保它与预期的数据类型（对象）相匹配。如有必要，转换数据类型或调整规则表达式以处理实际的数据类型。同时，验证您的JSON结构以确保其格式正确。
日志上下文 #
Log “failed to parse rules expression. expected [{}] to be an object but found [{}] instead” class name is RoleMapperExpressionParser.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
token = parser.nextToken();
} else {
token = parser.currentToken();
}
if (token != XContentParser.Token.START_OBJECT) {
throw new ElasticsearchParseException("failed to parse rules expression. expected [{}] to be an object but found [{}] instead";
objectName; token);
} final String fieldName = fieldName(objectName; parser);
final RoleMapperExpression expr = parseExpression(parser; fieldName; objectName);
