[每日一学]apache camel|BDD方式开发apache camel|Groovy|Spock

开发apache camel应用，最好的方式就是tdd,因为camel的每个组件都是相互独立并可测试的。

现在有很多好的测试框架，用groovy的Spock框架的BDD（行为测试驱动）是比较优秀和好用的。

首先， 我们从最简单的processor开始。

在maven工程文件pom.xml添加spock的依赖包：

<dependency>
  <groupId>org.codehaus.groovy</groupId>
  <artifactId>groovy-all</artifactId>
  <version>2.4.1</version>
</dependency>
<dependency>
  <groupId>org.spockframework</groupId>
  <artifactId>spock-core</artifactId>
  <version>1.0-groovy-2.4</version>
  <scope>test</scope>
</dependency>
完整的依赖包信息为：

<dependencies>
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-core</artifactId>
    <version>2.16.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-jms</artifactId>
    <version>2.16.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-spring</artifactId>
    <version>2.16.0</version>
  </dependency>

  <!-- the ActiveMQ client with connection pooling -->
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-client</artifactId>
    <version>5.12.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-camel</artifactId>
    <version>5.12.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-pool</artifactId>
    <version>5.12.0</version>
  </dependency>

  <!-- the ActiveMQ broker is optional and can be removed if connecting to a remote broker only -->
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-broker</artifactId>
    <version>5.12.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-spring</artifactId>
    <version>5.12.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.activemq</groupId>
    <artifactId>activemq-kahadb-store</artifactId>
    <version>5.12.0</version>
  </dependency>
  <dependency>
    <groupId>org.apache.xbean</groupId>
    <artifactId>xbean-spring</artifactId>
    <version>3.18</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>4.1.6.RELEASE</version>
  </dependency>

  <!-- logging -->
  <dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.12</version>
  </dependency>
  <dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.7.12</version>
  </dependency>
  <dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.17</version>
  </dependency>

  <!-- testing -->
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-test-spring</artifactId>
    <version>2.16.0</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>org.jolokia</groupId>
    <artifactId>jolokia-spring</artifactId>
    <classifier>plugin</classifier>
    <version>1.1.0</version>
  </dependency>
    <dependency>
      <groupId>org.codehaus.groovy</groupId>
      <artifactId>groovy-all</artifactId>
      <version>2.4.1</version>
    </dependency>
    <dependency>
      <groupId>org.spockframework</groupId>
      <artifactId>spock-core</artifactId>
      <version>1.0-groovy-2.4</version>
      <scope>test</scope>
    </dependency>

  <dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>19.0</version>
  </dependency>
</dependencies>

先写测试用例：

package com.github.eric.camel

import org.apache.camel.Exchange
import org.apache.camel.impl.DefaultCamelContext
import org.apache.camel.impl.DefaultExchange
import spock.lang.Specification

/**
 * Created by eric567 on 4/2/2016.
 */
class MyProcessorTest extends Specification {
    def "Process"() {
        given: "new MyProcessor,new Exchange ,new Context instance "
        def DefaultCamelContext contex = DefaultCamelContext.newInstance();
        def Exchange exchange = DefaultExchange.newInstance(contex)
        def MyProcessor myProcessor = new MyProcessor()
        when: "the body of exchange.in() is test"

        exchange.getIn().setBody("test");

        then: "the body to exchange.out() ins not null ,equals test"

        def Exchange ex = myProcessor.doProcess(exchange)
        ex.getIn().getBody(String.class) != null
        ex.getIn().getBody(String.class).equals("test")

    }
}

以下是被测试的代码 :

package com.github.eric.camel;

import org.apache.camel.Exchange;
import org.apache.camel.Processor;

/**
 * Created by eric567 on 4/2/2016.
 */
public class MyProcessor implements Processor {
    @Override
    public void process(Exchange exchange) throws Exception {
        String in = exchange.getIn(String.class);
        if(in!=null)
    {
        exchange.getOut().setBody(in);
    }
    }

    public Exchange doProcess(Exchange exchange) throws Exception {
        process(exchange);
        return exchange;
    }
}

因为Processor本身没有返回值，这里加了一个方法：doProcess用来返回exchange 对象，使 MyProcessor变得更好测试。
运行上面的spock测试用例，应该可以看到令人激动的绿色。cheers!!!