Error while indexing document in elasticsearch cluster - elasticsearch

Question

I'm not using BulkIndex request in my code.
Below is the Jest code used for indexing the document.
Builder builder = new Index.Builder(source).index(indexName).type(typeName)
.id(optionalDocId == null ? UUID.randomUUID().toString() : optionalDocId);
datatype of source is Map
Caused by: java.lang.Exception: ES Error Message while writing to raw: {"root_cause":[{"type":"remote_transport_exception","reason":"[datanodes-364022667-13-482069107.azure-ebf.opsds.cp.prod-az-westus-1.prod.us.walmart.net][10.12.10.171:9300][indices:data/write/bulk[s]]"}],"type":"es_rejected_execution_exception","reason":"rejected execution of processing of [557850852][indices:data/write/bulk[s][p]]: request: BulkShardRequest [[sceventstorev1][15]] containing [index {[SCEventStore][scevents][93adca0b-7404-4405-8f72-9fa5e32a167c], source[n/a, actual length: [2.1kb], max length: 2kb]}], target allocation id: iTbBHe7vT_ihTHdJwqVRhA, primary term: 7 on EsThreadPoolExecutor[name = datanodes-364022667-13-482069107.azure-ebf.opsds.cp.prod-az-westus-1.prod.us.walmart.net/write, queue capacity = 200, org.elasticsearch.common.util.concurrent.EsThreadPoolExecutor#4d2bc57e[Running, pool size = 8, active threads = 8, queued tasks = 200, completed tasks = 148755948]]"}
Given is the index mapping.
{
"sceventstore_v1": {
"mappings": {
"scevents": {
"properties": {
"eventID": {
"type": "keyword"
},
"eventId": {
"type": "keyword"
},
"eventName": {
"type": "keyword"
},
"message": {
"type": "text"
},
"producerName": {
"type": "keyword"
},
"receivedTimestamp": {
"type": "date",
"format": "epoch_millis"
},
"timestamp": {
"type": "date",
"format": "epoch_millis"
}
}
}
}
}
}```

Answer 1

The section of error message clearly explains the cause of it.
source[n/a, actual length: [2.1kb], max length: 2kb]}], it means max length allowed is 2kb somewhere configured in your application and you are sending more than which is 2.1 kb.
Try to inspect your document and see which field value is crossing this limit.
More resource can be found https://www.elastic.co/blog/why-am-i-seeing-bulk-rejections-in-my-elasticsearch-cluster and https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-threadpool.html