Briefly, this error occurs when Elasticsearch is unable to interpret the metadata of a model, possibly due to incorrect formatting, missing fields, or incompatible data types. To resolve this issue, you can: 1) Verify the format of your model metadata and ensure it adheres to the expected structure. 2) Check if all required fields are present and correctly named. 3) Ensure that the data types of your fields match the expected data types. 4) If the model was updated, ensure that the metadata is compatible with the new version of Elasticsearch.
This guide will help you check for common problems that cause the log ” [{}] failed to parse model metadata ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin, metadata.
Overview
Metadata in Elasticsearch refers to additional information stored for each document. This is achieved using the specific metadata fields available in Elasticsearch. The default behavior of some of these metadata fields can be customized during mapping creation.
Examples
Using _meta meta-field for storing application-specific information with the mapping:
PUT /my_index?pretty
{
"mappings": {
"_meta": {
"domain": "security",
"release_information": {
"date": "18-01-2020",
"version": "7.5"
}
}
}
}Notes
- In version 2.x, Elasticsearch had a total 13 meta fields available, which are: _index, _uid, _type, _id, _source, _size, _all, _field_names, _timestamp, _ttl, _parent, _routing, _meta
- In version 5.x, _timestamp and _ttl meta fields were removed.
- In version 6.x, the _parent meta field was removed.
- In version 7.x, _uid and _all meta fields were removed.
Log Context
Log “[{}] failed to parse model metadata” classname is TrainedModelProvider.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
XContentParser parser = XContentFactory.xContent(XContentType.JSON)
.createParser(xContentRegistry; LoggingDeprecationHandler.INSTANCE; stream)
) {
return TrainedModelMetadata.fromXContent(parser; true);
} catch (IOException e) {
logger.error(new ParameterizedMessage("[{}] failed to parse model metadata"; modelId); e);
throw e;
}
}
private IndexRequest createRequest(String docId; String index; ToXContentObject body) {
