jmeter添加自定义扩展函数之图片base64编码

打开eclipse，新建maven工程，在pom中引入jmeter核心jar包：

<!-- https://mvnrepository.com/artifact/org.apache.jmeter/ApacheJMeter_core -->
<dependency>
<groupId>org.apache.jmeter</groupId>
<artifactId>ApacheJMeter_core</artifactId>
<version>3.2</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.apache.jmeter/ApacheJMeter_functions -->
<dependency>
<groupId>org.apache.jmeter</groupId>
<artifactId>ApacheJMeter_functions</artifactId>
<version>3.2</version>
</dependency>

1. 新建一个包com.mytest.functions，包名要包含functions，因为jmeter.properties对这块有配置，可见该文件的classfinder.functions.contain=.functions.

2. 在该包下新建一个类并继承AbstractFunction，重写该类的所有方法，具体如下：

package com.mytest.functions;

import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.apache.jmeter.engine.util.CompoundVariable;
import org.apache.jmeter.functions.AbstractFunction;
import org.apache.jmeter.functions.InvalidVariableException;
import org.apache.jmeter.samplers.SampleResult;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.threads.JMeterVariables;

import sun.misc.BASE64Encoder;

public class MyBase64 extends AbstractFunction{

//自定义function的描述
private static final List<String> desc = new LinkedList<String>();
static {
desc.add("图片路径");
}
static {
desc.add("图片base64后存放变量");
}
private static final String KEY = "__MyBase64";

//存放传入参数的值的变量
private Object[] values;

//描述参数
public List<String> getArgumentDesc() {
// TODO Auto-generated method stub
return desc;
}

@Override
//函数的执行
public synchronized String execute(SampleResult arg0, Sampler arg1) throws InvalidVariableException {
// TODO Auto-generated method stub
JMeterVariables localJMeterVariables = getVariables();
String str1 = ((CompoundVariable)this.values[0]).execute();

String str2 = getImgBase64(str1);

if ((localJMeterVariables != null) && (this.values.length > 1)) {
String str3 = ((CompoundVariable)this.values[1]).execute().trim();
localJMeterVariables.put(str3, str2);
}

return str2;
}

@Override
public String getReferenceKey() {
// TODO Auto-generated method stub
//提供jmeter函数助手显示的名称
return KEY;
}

@Override
public synchronized void setParameters(Collection<CompoundVariable> arg0) throws InvalidVariableException {
// TODO Auto-generated method stub
//检查参数的个数，支持的方法有2个，具体用法参加api：
/**
* protected void checkParameterCount(Collection<CompoundVariable> parameters,
int count)
throws InvalidVariableException
Utility method to check parameter counts.
Parameters:
parameters - collection of parameters
count - number of parameters expected
* */
//-----------------
/**
*
* protected void checkParameterCount(Collection<CompoundVariable> parameters,
int min,
int max)
throws InvalidVariableException
Utility method to check parameter counts.
Parameters:
parameters - collection of parameters
min - minimum number of parameters allowed
max - maximum number of parameters allowed
* */
//checkParameterCount(arg0, 1);
checkParameterCount(arg0, 1, 2);
//将参数值存入变量中
this.values = arg0.toArray();

}
public String getImgBase64(String filePath) {
InputStream in = null;
byte[] data = null;
String result = null;
try {
in = new FileInputStream(filePath);
data = new byte[in.available()];
in.read(data);
in.close();

BASE64Encoder encoder = new BASE64Encoder();
result = encoder.encode(data);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

return result;
}

}

3. 由于我写的类没有依赖第三方jar包，引入的jmeter核心包都是jmeter自带的，所以直接导出上面的类为一个jar包，并把这个jar放在jmeter安装目录的apache-jmeter-3.2\lib\ext下面



4. 重启jmeter，打开函数助手，可看见如下图：



5. 下面我们测试一下这个函数是否能使用，新建一个http请求，在post请求里分别添加${__MyBase64(D:\\aa.jpg,imgresult)}和${imgresult}如下图，注意${__MyBase64(D:\\aa.jpg,imgresult)}一定要在上面



6. 运行后可以看到已经成功