Add the rabbitmq module

rabbitmq/src/main/java/com/ankurm/rabbit/ConverterConfiguration.java

@@ -0,0 +1,36 @@
+package com.ankurm.rabbit;
+
+import org.springframework.amqp.support.converter.JacksonJsonMessageConverter;
+import org.springframework.amqp.support.converter.MessageConverter;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Spring Boot does <b>not</b> auto-configure a JSON message converter for RabbitMQ. The default
+ * is {@code SimpleMessageConverter}, which handles {@code String}, {@code byte[]} and
+ * {@code Serializable} and nothing else:
+ *
+ * <pre>
+ * IllegalArgumentException: SimpleMessageConverter only supports String, byte[] and
+ * Serializable payloads, received: com.ankurm.rabbit.OrderMessage
+ * </pre>
+ *
+ * <p>Declaring one {@code MessageConverter} bean fixes both directions &mdash; the auto-configured
+ * {@code RabbitTemplate} and the listener container factory both pick it up.
+ *
+ * <p>Note the class name. Spring AMQP 4.1 ships {@code Jackson2JsonMessageConverter} (Jackson 2)
+ * and {@code JacksonJsonMessageConverter} (Jackson 3) side by side, exactly as Spring Kafka
+ * ships {@code JsonSerializer} and {@code JacksonJsonSerializer}. Boot 4 is a Jackson 3
+ * application; pick the one without the 2.
+ *
+ * @see <a href="../../../../../docs/01-the-on-ramp.md">docs/01-the-on-ramp.md</a>
+ */
+@Configuration(proxyBeanMethods = false)
+public class ConverterConfiguration {
+
+	@Bean
+	MessageConverter messageConverter() {
+		return new JacksonJsonMessageConverter();
+	}
+
+}