@Override
  public CompletableFuture<Void> deleteAsync(String key) {
    Preconditions.checkArgument(StringUtils.isNotBlank(key), "key must not be null, empty or blank");
    return asyncWriteHelper(
        bucket.async().remove(key, timeout.toMillis(), TimeUnit.MILLISECONDS),
        String.format("Failed to delete key %s from bucket %s.", key, bucketName));
  }
Construct an instance of {@link CouchbaseTableWriteFunction}.
@param bucketName Name of the couchbase bucket
@param clusterNodes Some Hosts of the Couchbase cluster. Recommended to provide more than one nodes so that if
                    the first node could not be connected, other nodes can be tried.
@param valueClass Type of values
samza-kv-couchbase/src/main/java/org/apache/samza/table/remote/couchbase/CouchbaseTableWriteFunction.java