flow:
    from:
      steps:
      - choice:
          otherwise:
            steps:
            - set-header:
                name: indexId
                simple: ${exchangeId}
          when:
          - simple: ${header[indexId]}
            steps:
            - set-header:
                name: indexId
                simple: ${header[indexId]}
          - simple: ${header[ce-indexId]}
            steps:
            - set-header:
                name: indexId
                simple: ${header[ce-indexId]}
      - choice:
          otherwise:
            steps:
            - set-header:
                name: indexName
                simple: ${exchangeId}
          when:
          - simple: ${header[indexName]}
            steps:
            - set-header:
                name: indexName
                simple: ${header[indexName]}
          - simple: ${header[ce-indexName]}
            steps:
            - set-header:
                name: indexName
                simple: ${header[ce-indexName]}

2021-07-21 12:29:13,521 WARN  [org.apa.cam.com.tim.TimerConsumer] (Camel (camel-1) thread #0 - timer://x) Error processing exchange. Exchange[8494CDA82FA3229-0000000000000000]. Caused by: [org.elasticsearch.ElasticsearchStatusException - Elasticsearch exception [type=invalid_index_name_exception, reason=Invalid index name [8494CDA82FA3229-0000000000000000], must be lowercase]]: [8494CDA82FA3229-0000000000000000] ElasticsearchStatusException[Elasticsearch exception [type=invalid_index_name_exception, reason=Invalid index name [8494CDA82FA3229-0000000000000000], must be lowercase]]
    at org.elasticsearch.rest.BytesRestResponse.errorFromXContent(BytesRestResponse.java:187)
    at org.elasticsearch.client.RestHighLevelClient.parseEntity(RestHighLevelClient.java:1907)
    at org.elasticsearch.client.RestHighLevelClient.parseResponseException(RestHighLevelClient.java:1884)
    at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1641)
    at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1598)
    at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1568)
    at org.elasticsearch.client.RestHighLevelClient.index(RestHighLevelClient.java:985)
    at org.apache.camel.component.elasticsearch.ElasticsearchProducer.process(ElasticsearchProducer.java:172)
    at org.apache.camel.support.AsyncProcessorConverterHelper$ProcessorToAsyncProcessorBridge.process(AsyncProcessorConverterHelper.java:66)
    at org.apache.camel.component.kameletreify.KameletReifyEndpoint$KameletProducer.process(KameletReifyEndpoint.java:143)
    at org.apache.camel.processor.SendProcessor.lambda$process$2(SendProcessor.java:191)
    at org.apache.camel.support.cache.DefaultProducerCache.doInAsyncProducer(DefaultProducerCache.java:318)
    at org.apache.camel.processor.SendProcessor.process(SendProcessor.java:190)
    at org.apache.camel.processor.errorhandler.RedeliveryErrorHandler$SimpleTask.run(RedeliveryErrorHandler.java:463)
    at org.apache.camel.impl.engine.DefaultReactiveExecutor$Worker.schedule(DefaultReactiveExecutor.java:179)
    at org.apache.camel.impl.engine.DefaultReactiveExecutor.scheduleMain(DefaultReactiveExecutor.java:64)
    at org.apache.camel.processor.Pipeline.process(Pipeline.java:184)
    at org.apache.camel.impl.engine.CamelInternalProcessor.process(CamelInternalProcessor.java:398)
    at org.apache.camel.component.timer.TimerConsumer.sendTimerExchange(TimerConsumer.java:209)
    at org.apache.camel.component.timer.TimerConsumer$1.run(TimerConsumer.java:76)
    at java.base/java.util.TimerThread.mainLoop(Timer.java:556)
    at java.base/java.util.TimerThread.run(Timer.java:506)
    Suppressed: org.elasticsearch.client.ResponseException: method [PUT], host [http://tnb-elasticsearch-es-http:9200], URI [/8494CDA82FA3229-0000000000000000/_doc/8494CDA82FA3229-0000000000000000?wait_for_active_shards=1&timeout=1m], status line [HTTP/1.1 400 Bad Request]                                                                                                                                                       
{"error":{"root_cause":[{"type":"invalid_index_name_exception","reason":"Invalid index name [8494CDA82FA3229-0000000000000000], must be lowercase","index_uuid":"_na_","index":"8494CDA82FA3229-0000000000000000"}],"type":"invalid_index_name_exception","reason":"Invalid index name [8494CDA82FA3229-0000000000000000], must be lowercase","index_uuid":"_na_","index":"8494CDA82FA3229-0000000000000000"},"status":400}
        at org.elasticsearch.client.RestClient.convertResponse(RestClient.java:318)
        at org.elasticsearch.client.RestClient.performRequest(RestClient.java:288)
        at org.elasticsearch.client.RestClient.performRequest(RestClient.java:262)
        at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1628)
        ... 18 more

// camel-k: language=java
package com.test;

import org.apache.camel.builder.RouteBuilder;

public class MyRouteBuilder extends RouteBuilder {
    private final String body = "{\"message\": \"Hello Elasticsearch c330b\"}";

    @Override
    public void configure() throws Exception {
        from("timer:x?repeatCount=1").setBody(constant(body)).to("kamelet:elasticsearch-index-sink?enableSSL=false&password=<pw>&clusterName=tnb-elasticsearch&user=elastic&hostAddresses=<address>");
    }
}