Apache Flink (v1.6.0) 验证 Elasticsearch Sink (v6.4)

Question

我正在使用 Apache Flink v1.6.0，我正在尝试写入托管在 Elastic Cloud 中的 Elasticsearch v6.4.0。我在向 Elastic Cloud 集群进行身份验证时遇到问题。

我已经能够使用以下代码让 Flink 写入本地 Elasticsearch v6.4.0 节点，该节点没有加密：

/*
    Elasticsearch Configuration
*/
List<HttpHost> httpHosts = new ArrayList<>();
httpHosts.add(new HttpHost("127.0.0.1", 9200, "http"));

// use a ElasticsearchSink.Builder to create an ElasticsearchSink
ElasticsearchSink.Builder<ObjectNode> esSinkBuilder = new ElasticsearchSink.Builder<>(
        httpHosts,
        new ElasticsearchSinkFunction<ObjectNode>() {
            private IndexRequest createIndexRequest(ObjectNode payload) {

                // remove the value node so the fields are at the base of the json payload
                JsonNode jsonOutput = payload.get("value");

                return Requests.indexRequest()
                        .index("raw-payload")
                        .type("payload")
                        .source(jsonOutput.toString(), XContentType.JSON);
            }

            @Override
            public void process(ObjectNode payload, RuntimeContext ctx, RequestIndexer indexer) {
                indexer.add(createIndexRequest(payload));
            }
        }
);

// set number of events to be seen before writing to Elasticsearch
esSinkBuilder.setBulkFlushMaxActions(1);

// finally, build and add the sink to the job's pipeline
stream.addSink(esSinkBuilder.build());

然而，当我尝试将身份验证添加到代码库中时，如相应 Elasticsearch Java 文档中所述 here in the Flink documentation and here。看起来像这样：

// provide a RestClientFactory for custom configuration on the internally created REST client
Header[] defaultHeaders = new Header[]{new BasicHeader("username", "password")};
esSinkBuilder.setRestClientFactory(
        restClientBuilder -> {
            restClientBuilder.setDefaultHeaders(defaultHeaders);
        }
);

执行作业时出现以下错误：

14:49:54,700 INFO  org.apache.flink.runtime.rpc.akka.AkkaRpcService              - Stopped Akka RPC service.
Exception in thread "main" org.apache.flink.runtime.client.JobExecutionException: org.elasticsearch.ElasticsearchStatusException: method [HEAD], host [https://XXXXXXXXXXXXXX.europe-west1.gcp.cloud.es.io:9243], URI [/], status line [HTTP/1.1 401 Unauthorized]
    at org.apache.flink.runtime.minicluster.MiniCluster.executeJobBlocking(MiniCluster.java:623)
    at org.apache.flink.streaming.api.environment.LocalStreamEnvironment.execute(LocalStreamEnvironment.java:123)
    at com.downuk.AverageStockSalePrice.main(AverageStockSalePrice.java:146)
Caused by: org.elasticsearch.ElasticsearchStatusException: method [HEAD], host [https://XXXXXXXXXXXXXX.europe-west1.gcp.cloud.es.io:9243], URI [/], status line [HTTP/1.1 401 Unauthorized]
    at org.elasticsearch.client.RestHighLevelClient.parseResponseException(RestHighLevelClient.java:625)

谁能帮我指出我错在哪里？

Answer 1

override def configureRestClientBuilder(restClientBuilder: RestClientBuilder): Unit = {
        // TODO Additional rest client args go here - authentication headers for secure connections etc...
      }
    })

希望对您有所帮助

Answer 2

在看了 Flink 示例后，我能够解决这个问题 here and the Elasticsearch documentation here。

原来是我在上面设置错误的配置：

restClientBuilder.setDefaultHeaders(...);

不是实际需要设置的是：

restClientBuilder.setHttpClientConfigCallback(...);

一旦您使用了正确的自定义配置，剩下的就很简单了。所以我缺少的部分是：

// provide a RestClientFactory for custom configuration on the internally created REST client
esSinkBuilder.setRestClientFactory(
    restClientBuilder -> {
        restClientBuilder.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
            @Override
            public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder) {

                // elasticsearch username and password
                CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
                credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("$USERNAME", "$PASSWORD"));

                return httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
            }
        });
    }
);

最后是 Elasticsearch Sink 的完整代码段：

/*
    Elasticsearch Configuration
*/
List<HttpHost> httpHosts = new ArrayList<>();
httpHosts.add(new HttpHost("127.0.0.1", 9200, "http"));

// use a ElasticsearchSink.Builder to create an ElasticsearchSink
ElasticsearchSink.Builder<ObjectNode> esSinkBuilder = new ElasticsearchSink.Builder<>(
        httpHosts,
        new ElasticsearchSinkFunction<ObjectNode>() {
            private IndexRequest createIndexRequest(ObjectNode payload) {

                // remove the value node so the fields are at the base of the json payload
                JsonNode jsonOutput = payload.get("value");

                return Requests.indexRequest()
                        .index("raw-payload")
                        .type("payload")
                        .source(jsonOutput.toString(), XContentType.JSON);
            }

            @Override
            public void process(ObjectNode payload, RuntimeContext ctx, RequestIndexer indexer) {
                indexer.add(createIndexRequest(payload));
            }
        }
);

// set number of events to be seen before writing to Elasticsearch
esSinkBuilder.setBulkFlushMaxActions(1);

// provide a RestClientFactory for custom configuration on the internally created REST client
esSinkBuilder.setRestClientFactory(
    restClientBuilder -> {
        restClientBuilder.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
            @Override
            public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder) {

                // elasticsearch username and password
                CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
                credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("$USERNAME", "$PASSWORD"));

                return httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
            }
        });
    }
);

// finally, build and add the sink to the job's pipeline
stream.addSink(esSinkBuilder.build());

我希望这可以帮助其他被困在同一个地方的人！