Examples

Working examples are available in the examples/java directory as a Gradle project. The following example sets are included:

gettingstarted - basic blocking TCP producer and consumer
async - asynchronous producer and consumer
messageenvelope - JSON message envelope pattern
messageheaders - custom message headers
multitenant - multi-tenant isolation with per-tenant streams
tcptls - TLS-encrypted TCP connections
sinkdataproducer - bulk random data generation
streambuilder - combined producer and consumer in one class

Producer

import org.apache.iggy.client.blocking.tcp.IggyTcpClient;
import org.apache.iggy.identifier.StreamId;
import org.apache.iggy.identifier.TopicId;
import org.apache.iggy.message.Message;
import org.apache.iggy.message.Partitioning;
import org.apache.iggy.topic.CompressionAlgorithm;
import java.math.BigInteger;
import java.util.List;
import static java.util.Optional.empty;

public class Producer {

    static final String STREAM_NAME = "sample-stream";
    static final StreamId STREAM_ID = StreamId.of(STREAM_NAME);
    static final String TOPIC_NAME = "sample-topic";
    static final TopicId TOPIC_ID = TopicId.of(TOPIC_NAME);

    public static void main(String[] args) {
        try (var client = IggyTcpClient.builder()
                .host("127.0.0.1")
                .port(8090)
                .credentials("iggy", "iggy")
                .buildAndLogin()) {

            // Re-running this example is fine: only create what is missing.
            if (client.streams().getStream(STREAM_ID).isEmpty()) {
                client.streams().createStream(STREAM_NAME);
            }
            if (client.topics().getTopic(STREAM_ID, TOPIC_ID).isEmpty()) {
                client.topics().createTopic(
                        STREAM_ID,
                        1L,
                        CompressionAlgorithm.None,
                        BigInteger.ZERO,
                        BigInteger.ZERO,
                        empty(),
                        TOPIC_NAME);
            }

            Partitioning partitioning = Partitioning.partitionId(0L);
            for (int i = 0; i < 10; i++) {
                String payload = "message-" + i;
                client.messages().sendMessages(
                        STREAM_ID,
                        TOPIC_ID,
                        partitioning,
                        List.of(Message.of(payload)));
                System.out.println("Sent: " + payload);
            }
        }
    }
}

Consumer

import org.apache.iggy.client.blocking.tcp.IggyTcpClient;
import org.apache.iggy.consumergroup.Consumer;
import org.apache.iggy.identifier.StreamId;
import org.apache.iggy.identifier.TopicId;
import org.apache.iggy.message.Message;
import org.apache.iggy.message.PolledMessages;
import org.apache.iggy.message.PollingStrategy;
import java.math.BigInteger;
import java.nio.charset.StandardCharsets;
import java.util.Optional;

public class ConsumerExample {

    static final StreamId STREAM_ID = StreamId.of("sample-stream");
    static final TopicId TOPIC_ID = TopicId.of("sample-topic");

    public static void main(String[] args) {
        try (var client = IggyTcpClient.builder()
                .host("127.0.0.1")
                .port(8090)
                .credentials("iggy", "iggy")
                .buildAndLogin()) {

            BigInteger offset = BigInteger.ZERO;
            Consumer consumer = Consumer.of(0L);

            while (true) {
                PolledMessages polledMessages = client.messages().pollMessages(
                        STREAM_ID,
                        TOPIC_ID,
                        Optional.of(0L),
                        consumer,
                        PollingStrategy.offset(offset),
                        10L,
                        false);

                if (polledMessages.messages().isEmpty()) {
                    break;
                }
                for (Message message : polledMessages.messages()) {
                    String payload = new String(message.payload(), StandardCharsets.UTF_8);
                    System.out.printf("Offset: %d, Payload: %s%n", message.header().offset(), payload);
                }
                offset = offset.add(BigInteger.valueOf(polledMessages.messages().size()));
            }
        }
    }
}

For the full source code, see the examples/java directory.

Producer

Consumer

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