in flink-connector-elasticsearch6/src/main/java/org/apache/flink/streaming/connectors/elasticsearch6/Elasticsearch6ApiCallBridge.java [134:146]
public void verifyClientConnection(RestHighLevelClient client) throws IOException {
if (LOG.isInfoEnabled()) {
LOG.info("Pinging Elasticsearch cluster via hosts {} ...", httpHosts);
}
if (!client.ping()) {
throw new RuntimeException("There are no reachable Elasticsearch nodes!");
}
if (LOG.isInfoEnabled()) {
LOG.info("Elasticsearch RestHighLevelClient is connected to {}", httpHosts.toString());
}
}