Add consumer example

examples/simple-consumer/build.gradle.kts

@@ -0,0 +1,16 @@
+plugins {
+    id("java")
+}
+
+group = "rs.iggy"
+version = "0.0.1-SNAPSHOT"
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation(project(":sdk"))
+    implementation("org.slf4j:slf4j-api:2.0.9")
+    runtimeOnly("ch.qos.logback:logback-classic:1.4.12")
+}

examples/simple-consumer/src/main/java/rs/iggy/SimpleConsumer.java

@@ -0,0 +1,95 @@
+package rs.iggy;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import rs.iggy.clients.blocking.tcp.IggyTcpClient;
+import rs.iggy.consumergroup.Consumer;
+import rs.iggy.consumergroup.ConsumerGroupDetails;
+import rs.iggy.identifier.ConsumerId;
+import rs.iggy.identifier.StreamId;
+import rs.iggy.identifier.TopicId;
+import rs.iggy.message.Message;
+import rs.iggy.message.PolledMessages;
+import rs.iggy.message.PollingKind;
+import rs.iggy.message.PollingStrategy;
+import rs.iggy.stream.StreamDetails;
+import rs.iggy.topic.CompressionAlgorithm;
+import rs.iggy.topic.TopicDetails;
+import java.math.BigInteger;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import static java.util.Optional.empty;
+
+public class SimpleConsumer {
+
+    private static final String STREAM_NAME = "dev01";
+    private static final StreamId STREAM_ID = StreamId.of(STREAM_NAME);
+    private static final String TOPIC_NAME = "events";
+    private static final TopicId TOPIC_ID = TopicId.of(TOPIC_NAME);
+    private static final String GROUP_NAME = "simple-consumer";
+    private static final ConsumerId GROUP_ID = ConsumerId.of(GROUP_NAME);
+    private static final Logger log = LoggerFactory.getLogger(SimpleConsumer.class);
+
+    public static void main(String[] args) {
+        IggyTcpClient client = new IggyTcpClient("localhost", 8090);
+        client.users().login("iggy", "iggy");
+
+        createStream(client);
+        createTopic(client);
+        createConsumerGroup(client);
+        client.consumerGroups().joinConsumerGroup(STREAM_ID, TOPIC_ID, GROUP_ID);
+
+        List<Message> messages = new ArrayList<>();
+        while (messages.size() < 1000) {
+            PolledMessages polledMessages = client.messages()
+                    .pollMessages(STREAM_ID,
+                            TOPIC_ID,
+                            empty(),
+                            new Consumer(Consumer.Kind.ConsumerGroup, GROUP_ID),
+                            new PollingStrategy(PollingKind.Next, BigInteger.ZERO),
+                            10L,
+                            true);
+            messages.addAll(polledMessages.messages());
+            log.debug("Fetched {} messages from partition {}, current offset {}",
+                    polledMessages.messages().size(),
+                    polledMessages.partitionId(),
+                    polledMessages.currentOffset());
+        }
+    }
+
+    private static void createStream(IggyTcpClient client) {
+        Optional<StreamDetails> stream = client.streams().getStream(STREAM_ID);
+        if (stream.isPresent()) {
+            return;
+        }
+        client.streams().createStream(empty(), STREAM_NAME);
+    }
+
+    private static void createTopic(IggyTcpClient client) {
+        Optional<TopicDetails> topic = client.topics().getTopic(STREAM_ID, TOPIC_ID);
+        if (topic.isPresent()) {
+            return;
+        }
+        client.topics()
+                .createTopic(STREAM_ID,
+                        empty(),
+                        1L,
+                        CompressionAlgorithm.none,
+                        BigInteger.ZERO,
+                        BigInteger.ZERO,
+                        empty(),
+                        TOPIC_NAME);
+
+    }
+
+    private static void createConsumerGroup(IggyTcpClient client) {
+        Optional<ConsumerGroupDetails> consumerGroup = client.consumerGroups()
+                .getConsumerGroup(STREAM_ID, TOPIC_ID, GROUP_ID);
+        if (consumerGroup.isPresent()) {
+            return;
+        }
+        client.consumerGroups().createConsumerGroup(STREAM_ID, TOPIC_ID, empty(), GROUP_NAME);
+    }
+
+}

settings.gradle.kts

@@ -1,2 +1,6 @@
 rootProject.name = "iggy-java-client"
+
 include("sdk")
+
+include("simple-consumer-example")
+project(":simple-consumer-example").projectDir = file("examples/simple-consumer")