Spring Boot 2.2.0 with Micrometer 1.3.0 for ElasticSearch 7.1 not working

I’m trying to get the basic metrics into the ElasticSearch index on AWS. I’m using Spring Boot 2.2.0 with WebFlux. For Micrometer I’m using Elastic Registry 1.3.0. After starting the app, I’m getting these errors on the app side:

2019-11-04 10:56:24.495 ERROR 1510 --- [trics-publisher] i.m.elastic.ElasticMeterRegistry : failed to send metrics to elastic (sent 55 metrics but created 0 metrics):
{
    "took": 0,
    "errors": true,
    "items": [
        {
            "index": {
                "_index": "",
                "_type": "metrics-2019-11",
                "_id": null,
                "status": 500,
                "error": {
                    "type": "string_index_out_of_bounds_exception",
                    "reason": "String index out of range: 0"
                }
            }
        }, ...

And on the ElasticSearch side, the error is this:

[2019-11-04T02:48:01,553][WARN ][r.suppressed ] [76ba019e12d26993bb1160a3b9e7e9b0] path: __PATH__ params: {index=, id=metrics_template, type=_template}
java.lang.StringIndexOutOfBoundsException: String index out of range: 0
at java.lang.String.charAt(String.java:658) ~[?:1.8.0_172]
at org.elasticsearch.cluster.metadata.MetaDataCreateIndexService.validateIndexOrAliasName(MetaDataCreateIndexService.java:172) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.metadata.MetaDataCreateIndexService.validateIndexName(MetaDataCreateIndexService.java:144) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.metadata.MetaDataCreateIndexService.validate(MetaDataCreateIndexService.java:608) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.metadata.MetaDataCreateIndexService$IndexCreationTask.execute(MetaDataCreateIndexService.java:286) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.ClusterStateUpdateTask.execute(ClusterStateUpdateTask.java:47) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.MasterService.executeTasks(MasterService.java:687) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.MasterService.calculateTaskOutputs(MasterService.java:310) ~[elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.MasterService.runTasks(MasterService.java:210) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.MasterService$Batcher.run(MasterService.java:142) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.TaskBatcher.runIfNotProcessed(TaskBatcher.java:150) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.cluster.service.TaskBatcher$BatchedTask.run(TaskBatcher.java:188) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:690) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.runAndClean(PrioritizedEsThreadPoolExecutor.java:252) [elasticsearch-7.1.1.jar:7.1.1]
at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.run(PrioritizedEsThreadPoolExecutor.java:215) [elasticsearch-7.1.1.jar:7.1.1]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_172]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_172]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_172]

I did a basic endpoint configuration and that is all. I also tried setting the index name into the application.yml but it did not help.

Any ideas on how to overcome this issue?

[kvaidas]

I might have had this issue recently which I think I solved by removing a trailing forward slash in management.metrics.export.elastic.host.

[nemanjanedic]

Sorry for not able to answer before. I did manage to make this working with the latest standalone version of ElasticSearch (7.4.2) with the Bitnami AWS image. If I have time in the upcoming weeks, I’ll create a sample app with the AWS managed ELK stack.