Endless Producer: a simple producer, implemented as Spring-Boot-App

[demos/kafka/training] / src / main / java / de / juplo / kafka / EndlessProducer.java

diff --git a/src/main/java/de/juplo/kafka/EndlessProducer.java b/src/main/java/de/juplo/kafka/EndlessProducer.java
new file mode 100644 (file)
index 0000000..43b0e41
--- /dev/null
+++ b/src/main/java/de/juplo/kafka/EndlessProducer.java
@@ -0,0 +1,171 @@
+package de.juplo.kafka;
+
+import lombok.extern.slf4j.Slf4j;
+import org.apache.kafka.clients.producer.KafkaProducer;
+import org.apache.kafka.clients.producer.ProducerRecord;
+import org.apache.kafka.common.serialization.StringSerializer;
+
+import javax.annotation.PreDestroy;
+import java.util.Properties;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+
+
+@Slf4j
+public class EndlessProducer implements Runnable
+{
+  private final ExecutorService executor;
+  private final String id;
+  private final String topic;
+  private final String acks;
+  private final int throttleMs;
+  private final KafkaProducer<String, String> producer;
+
+  private boolean running = false;
+  private long i = 0;
+  private long produced = 0;
+  private Future<?> future = null;
+
+  public EndlessProducer(
+      ExecutorService executor,
+      String bootstrapServer,
+      String clientId,
+      String topic,
+      String acks,
+      int throttleMs)
+  {
+    this.executor = executor;
+    this.id = clientId;
+    this.topic = topic;
+    this.acks = acks;
+    this.throttleMs = throttleMs;
+
+    Properties props = new Properties();
+    props.put("bootstrap.servers", bootstrapServer);
+    props.put("client.id", clientId);
+    props.put("acks", acks);
+    props.put("key.serializer", StringSerializer.class.getName());
+    props.put("value.serializer", StringSerializer.class.getName());
+
+    this.producer = new KafkaProducer<>(props);
+  }
+
+  @Override
+  public void run()
+  {
+    try
+    {
+      for (; running; i++)
+      {
+        final long time = System.currentTimeMillis();
+
+        final ProducerRecord<String, String> record = new ProducerRecord<>(
+            topic,                 // Topic
+            Long.toString(i % 10), // Key
+            Long.toString(i)       // Value
+        );
+
+        producer.send(record, (metadata, e) ->
+        {
+          long now = System.currentTimeMillis();
+          if (e == null)
+          {
+            // HANDLE SUCCESS
+            produced++;
+            log.debug(
+                "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
+                id,
+                record.key(),
+                record.value(),
+                metadata.partition(),
+                metadata.offset(),
+                metadata.timestamp(),
+                now - time
+            );
+          }
+          else
+          {
+            // HANDLE ERROR
+            log.error(
+                "{} - ERROR key={} timestamp={} latency={}ms: {}",
+                id,
+                record.key(),
+                metadata == null ? -1 : metadata.timestamp(),
+                now - time,
+                e.toString()
+            );
+          }
+        });
+
+        long now = System.currentTimeMillis();
+        log.trace(
+            "{} - Queued #{} key={} latency={}ms",
+            id,
+            i,
+            record.key(),
+            now - time
+        );
+
+        if (throttleMs > 0)
+        {
+          try
+          {
+            Thread.sleep(throttleMs);
+          }
+          catch (InterruptedException e)
+          {
+            log.warn("{} - Interrupted while throttling!", e);
+          }
+        }
+      }
+
+      log.info("{} - Done", id);
+    }
+    catch (Exception e)
+    {
+
+    }
+  }
+
+  public synchronized void start()
+  {
+    if (running)
+      throw new IllegalStateException("Producer instance " + id + " is already running!");
+
+    log.info("{} - Starting - produced {} messages before", id, produced);
+    running = true;
+    future = executor.submit(this);
+  }
+
+  public synchronized void stop() throws ExecutionException, InterruptedException
+  {
+    if (!running)
+      throw new IllegalStateException("Producer instance " + id + " is not running!");
+
+    log.info("{} - Stopping...", id);
+    running = false;
+    future.get();
+    log.info("{} - Stopped - produced {} messages so far", id, produced);
+  }
+
+  @PreDestroy
+  public void destroy() throws ExecutionException, InterruptedException
+  {
+    log.info("{} - Destroy!", id);
+    try
+    {
+      stop();
+    }
+    catch (IllegalStateException e)
+    {
+      log.info("{} - Was already stopped", id);
+    }
+    finally
+    {
+      log.info("{} - Closing the KafkaProducer", id);
+      producer.close();
+      log.info("{}: Produced {} messages in total, exiting!", id, produced);
+    }
+  }
+}