spring-amqp-hessian

spring-amqp-hessian is based on qpid-hessian component (https://github.com/ebourg/qpid-hessian) and adapted for spring-amqp.

spring-amqp-hessian is a component helping the creation of Hessian services over AMQP using spring-amqp.

Usage

Server side :

Add Maven dependency to your pom.xml (stable artifact are available from Maven Central repository). Repository for SNAPSHOT versions : https://oss.sonatype.org/content/repositories/snapshots

<dependency>
    <groupId>org.resthub</groupId>
    <artifactId>spring-amqp-hessian</artifactId>
    <version>1.0.3</version>
</dependency>

Declare your service implementation and the endpoint in your Spring configuration file :

<bean id="echoServiceImpl" class="org.resthub.rpc.service.EchoServiceImpl"/>
<bean id="echoEndpoint" class="org.resthub.rpc.HessianEndpoint">
    <constructor-arg index="0" ref="echoServiceImpl"/>
    <property name="connectionFactory" ref="connectionFactory" />
</bean>

Hibernate/JPA Lazy collections

If you are working with lazy collections, you can add a custom serializer for hibernate :

<bean id="hibernateSerializerFactory" class="org.resthub.rpc.serializer.HibernateSerializerFactory" />
<bean id="echoEndpoint" class="org.resthub.rpc.HessianEndpoint">
    <constructor-arg index="0" ref="echoServiceImpl"/>
    <property name="connectionFactory" ref="connectionFactory" />
    <property name="serializerFactory" ref="hibernateSerializerFactory" />
</bean>

This custom serializer will serialize initialized collections (List, Set or Map), and serialize an empty collection if it's not initialized.

Client side :

Declare the proxy in your Spring configuration file :

<bean id="echoService" class="org.resthub.rpc.AMQPHessianProxyFactoryBean">
    <property name="connectionFactory" ref="connectionFactory"/>
    <property name="serviceInterface" value="org.resthub.rpc.service.EchoService"/>
</bean>

You can now consume the service :

String echo = echoService.echo("Hello Hessian!");

Specifications

Exceptions management

Exceptions on server side when calling a method are catched and sent to the client. Exceptions can be catched on client side :

try {
    String echo = echoService.echo("Hello Hessian!");
} catch (Exception e) {
    //do stuff
}

Partial serialization

Objects on server side can have more attributes than same objects on client side.

Indicative performance

In addition to the benefits of monitoring and configuration provided by RabbitMQ, it gives better performance than REST webservices.

Comparative bench between spring-amqp-hessian with RabbitMQ and REST/JSON :

Test with spring-amqp-hessian and RabbitMQ 2.6.1 :

* Average of 2800 requests per second

Same test with REST/JSON :

* Average of 1800 requests per second