Cassandra Sidecar Client

The Sidecar Client is a fully featured client to access Cassandra Sidecar endpoints. It offers support for retries and Sidecar instance selection policies. The client project itself is technology-agnostic, but we provide a vertx implementation for the HttpClient.

Usage

The SidecarClient provides convenience methods to access the sidecar service endpoints. For example, to access the ring endpoint we will need to do the following.

CompletableFuture<RingResponse> ringFuture = sidecarClient.ring(keyspace);

To instantiate the SidecarClient, an implementation of the RequestExecutor must be provided. Here is an example on how to instantiate the SidecarClient using vertx's implementation:

        Vertx vertx = Vertx.vertx(new VertxOptions().setWorkerPoolSize(16));

        HttpClientConfig httpClientConfig = new HttpClientConfig.Builder<>()
                                            .ssl(false)
                                            .timeoutMillis(10_000)
                                            .idleTimeoutMillis(30_000)
                                            .receiveBufferSize(8196)
                                            .maxChunkSize(4092)
                                            .userAgent("sample-agent/0.0.1")
                                            .build();

        SidecarClientConfig clientConfig = new SidecarClientConfig.Builder()
                                      .maxRetries(10)
                                      .retryDelayMillis(200)
                                      .maxRetryDelayMillis(10_000)
                                      .build();

        RetryPolicy defaultRetryPolicy = new ExponentialBackoffRetryPolicy(clientConfig.maxRetries(),
                                                                           clientConfig.retryDelayMillis(),
                                                                           clientConfig.maxRetryDelayMillis());

        VertxHttpClient vertxHttpClient = new VertxHttpClient(vertx, httpClientConfig);
        VertxRequestExecutor requestExecutor = new VertxRequestExecutor(vertxHttpClient);
        SimpleSidecarInstancesProvider instancesProvider = new SimpleSidecarInstancesProvider(new ArrayList<>(clusterConfig));
        return new SidecarClient(instancesProvider, requestExecutor, clientConfig, defaultRetryPolicy);