使用 JMeter，如何从 API 响应的 body 中提取字符串并将其保存到 csv 文件？

Question

我从 API 收到了一些不同的 body 回复，看起来像这样：

"eyJhbRciOiRRRzI1RiIsInR5cCI6IkpXVCJ9.eyJ1c2RybmRtZSI6IlRlcmhhdCIsInR1aWQiOiJRZXJoYXQiLRJyb2xlRjoibW9iaWxlRRRwcCIsImVtYWlsIjoidGVzdEB0ZXN0LmNvbSIsImlkIjoiU2RyaGF0IiwiaWR0IjoxRRR5MDU5OTUxLCJleRRiOjE1NRkwNzQzRRR9.RRzm3VvioZ_iR-v5EGSSfYJLf0d9aZ-9R-RP4UbER04"

我正在使用 JMeter 的正则表达式提取器提取它，如下所示：

如何将正则表达式提取器的值打印到 .csv 文件以供以后在不同的测试中使用？

我尝试了此处提供的解决方案，但没有帮助。也许该脚本需要更多调整，但我没有 groovy 知识：

如果您能提供任何帮助，我将不胜感激。

更新问题： 使用前面提到的问题的答案中的确切代码，我会得到以下错误：

代码：

def csv = new File("my.csv")
1.upto(vars.get("foo_matchNr") as int, {
    csv << vars.get("foo_$it") << System.getProperty("line.separator")  
})

错误：

    019-02-02 11:30:26,972 INFO o.a.j.e.StandardJMeterEngine: Running the test!
2019-02-02 11:30:26,974 INFO o.a.j.s.SampleEvent: List of sample_variables: []
2019-02-02 11:30:26,978 INFO o.a.j.g.u.JMeterMenuBar: setRunning(true, *local*)
2019-02-02 11:30:27,223 INFO o.a.j.e.StandardJMeterEngine: Starting ThreadGroup: 1 : Thread Group
2019-02-02 11:30:27,223 INFO o.a.j.e.StandardJMeterEngine: Starting 3 threads for group Thread Group.
2019-02-02 11:30:27,223 INFO o.a.j.e.StandardJMeterEngine: Thread will continue on error
2019-02-02 11:30:27,224 INFO o.a.j.t.ThreadGroup: Starting thread group... number=1 threads=3 ramp-up=1 perThread=333.33334 delayedStart=false
2019-02-02 11:30:27,226 INFO o.a.j.t.ThreadGroup: Started thread group number 1
2019-02-02 11:30:27,225 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-1
2019-02-02 11:30:27,226 INFO o.a.j.s.FileServer: Stored: D:/Software/apache-jmeter-5.0/bin/testUser.csv
2019-02-02 11:30:27,226 INFO o.a.j.e.StandardJMeterEngine: All thread groups have been started
2019-02-02 11:30:27,559 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-2
2019-02-02 11:30:27,892 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-3
2019-02-02 11:30:28,428 ERROR o.a.j.e.JSR223PostProcessor: Problem in JSR223 script, JSR223 PostProcessor
javax.script.ScriptException: org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object 'null' with class 'null' to class 'int'. Try 'java.lang.Integer' instead
    at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval(GroovyScriptEngineImpl.java:324) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.jsr223.GroovyCompiledScript.eval(GroovyCompiledScript.java:72) ~[groovy-all-2.4.15.jar:2.4.15]
    at javax.script.CompiledScript.eval(Unknown Source) ~[?:1.8.0_191]
    at org.apache.jmeter.util.JSR223TestElement.processFileOrScript(JSR223TestElement.java:221) ~[ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.extractor.JSR223PostProcessor.process(JSR223PostProcessor.java:44) [ApacheJMeter_components.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.runPostProcessors(JMeterThread.java:925) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.executeSamplePackage(JMeterThread.java:564) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.processSampler(JMeterThread.java:486) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:253) [ApacheJMeter_core.jar:5.0 r1840935]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_191]
Caused by: org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object 'null' with class 'null' to class 'int'. Try 'java.lang.Integer' instead
    at org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation.castToNumber(DefaultTypeTransformation.java:176) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation.intUnbox(DefaultTypeTransformation.java:82) ~[groovy-all-2.4.15.jar:2.4.15]
    at Script5.run(Script5.groovy:2) ~[?:?]
    at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval(GroovyScriptEngineImpl.java:321) ~[groovy-all-2.4.15.jar:2.4.15]
    ... 9 more
2019-02-02 11:30:28,436 INFO o.a.j.t.JMeterThread: Thread is done: Thread Group 1-1
2019-02-02 11:30:28,439 INFO o.a.j.t.JMeterThread: Thread finished: Thread Group 1-1
2019-02-02 11:30:28,583 ERROR o.a.j.e.JSR223PostProcessor: Problem in JSR223 script, JSR223 PostProcessor
javax.script.ScriptException: org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object 'null' with class 'null' to class 'int'. Try 'java.lang.Integer' instead
    at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval(GroovyScriptEngineImpl.java:324) ~[groovy-all-2.4.15.jar:2.4.15]

等等

还有 2 个这样的错误。

我认为 "foo_matchNr" 被视为一个变量，而 "foo" 是我的变量，它每次都会改变它的值，或者它是一个值列表？我不知道这个正则表达式提取器是如何工作的，或者 groovy 就此而言。

使用从前面提到的问题的答案改编的代码（使用我对 groovy 代码的 0 级知识），我会得到以下错误：

更改代码：

def csv = new File("my.csv")
1.upto(vars.get("foo") as int, {
    csv << vars.get("foo_$it") << System.getProperty("line.separator")  
})

错误：

2019-02-02 11:08:27,613 INFO o.a.j.e.StandardJMeterEngine: Running the test!
2019-02-02 11:08:27,614 INFO o.a.j.s.SampleEvent: List of sample_variables: []
2019-02-02 11:08:27,635 INFO o.a.j.g.u.JMeterMenuBar: setRunning(true, *local*)
2019-02-02 11:08:27,850 INFO o.a.j.e.StandardJMeterEngine: Starting ThreadGroup: 1 : Thread Group
2019-02-02 11:08:27,850 INFO o.a.j.e.StandardJMeterEngine: Starting 3 threads for group Thread Group.
2019-02-02 11:08:27,850 INFO o.a.j.e.StandardJMeterEngine: Thread will continue on error
2019-02-02 11:08:27,850 INFO o.a.j.t.ThreadGroup: Starting thread group... number=1 threads=3 ramp-up=1 perThread=333.33334 delayedStart=false
2019-02-02 11:08:27,851 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-1
2019-02-02 11:08:27,852 INFO o.a.j.s.FileServer: Stored: D:/Software/apache-jmeter-5.0/bin/testUser.csv
2019-02-02 11:08:27,853 INFO o.a.j.t.ThreadGroup: Started thread group number 1
2019-02-02 11:08:27,853 INFO o.a.j.e.StandardJMeterEngine: All thread groups have been started
2019-02-02 11:08:28,187 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-2
2019-02-02 11:08:28,520 INFO o.a.j.t.JMeterThread: Thread started: Thread Group 1-3
2019-02-02 11:08:28,794 ERROR o.a.j.e.JSR223PostProcessor: Problem in JSR223 script, JSR223 PostProcessor
javax.script.ScriptException: java.lang.NumberFormatException: For input string: "eyJhbRciOiRRRzI1RiIsInR5cCI6IkpXVCJ9.eyJ1c2RybmRtZSI6IlRlcmhhdCIsInR1aWQiOiJRZXJoYXQiLRJyb2xlRjoibW9iaWxlRRRwcCIsImVtYWlsIjoidGVzdEB0ZXN0LmNvbSIsImlkIjoiU2RyaGF0IiwiaWR0IjoxRRR5MDU5OTUxLCJleRRiOjE1NRkwNzQzRRR9.RRzm3VvioZ_iR-v5EGSSfYJLf0d9aZ-9R-RP4UbER04"
    at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval(GroovyScriptEngineImpl.java:324) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.jsr223.GroovyCompiledScript.eval(GroovyCompiledScript.java:72) ~[groovy-all-2.4.15.jar:2.4.15]
    at javax.script.CompiledScript.eval(Unknown Source) ~[?:1.8.0_191]
    at org.apache.jmeter.util.JSR223TestElement.processFileOrScript(JSR223TestElement.java:221) ~[ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.extractor.JSR223PostProcessor.process(JSR223PostProcessor.java:44) [ApacheJMeter_components.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.runPostProcessors(JMeterThread.java:925) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.executeSamplePackage(JMeterThread.java:564) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.processSampler(JMeterThread.java:486) [ApacheJMeter_core.jar:5.0 r1840935]
    at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:253) [ApacheJMeter_core.jar:5.0 r1840935]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_191]
Caused by: java.lang.NumberFormatException: For input string: "eyJhbRciOiRRRzI1RiIsInR5cCI6IkpXVCJ9.eyJ1c2RybmRtZSI6IlRlcmhhdCIsInR1aWQiOiJRZXJoYXQiLRJyb2xlRjoibW9iaWxlRRRwcCIsImVtYWlsIjoidGVzdEB0ZXN0LmNvbSIsImlkIjoiU2RyaGF0IiwiaWR0IjoxRRR5MDU5OTUxLCJleRRiOjE1NRkwNzQzRRR9.RRzm3VvioZ_iR-v5EGSSfYJLf0d9aZ-9R-RP4UbER04"
    at java.lang.NumberFormatException.forInputString(Unknown Source) ~[?:1.8.0_191]
    at java.lang.Integer.parseInt(Unknown Source) ~[?:1.8.0_191]
    at java.lang.Integer.valueOf(Unknown Source) ~[?:1.8.0_191]
    at org.codehaus.groovy.runtime.StringGroovyMethods.toInteger(StringGroovyMethods.java:3319) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.StringGroovyMethods.asType(StringGroovyMethods.java:178) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.dgm48.doMethodInvoke(Unknown Source) ~[groovy-all-2.4.15.jar:2.4.15]
    at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1225) ~[groovy-all-2.4.15.jar:2.4.15]
    at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1034) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.InvokerHelper.invokePojoMethod(InvokerHelper.java:935) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:926) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeMethodN(ScriptBytecodeAdapter.java:181) ~[groovy-all-2.4.15.jar:2.4.15]
    at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.asType(ScriptBytecodeAdapter.java:604) ~[groovy-all-2.4.15.jar:2.4.15]
    at Script4.run(Script4.groovy:2) ~[?:?]
    at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval(GroovyScriptEngineImpl.java:321) ~[groovy-all-2.4.15.jar:2.4.15]
    ... 9 more
2019-02-02 11:08:28,797 INFO o.a.j.t.JMeterThread: Thread is done: Thread Group 1-1
2019-02-02 11:08:28,797 INFO o.a.j.t.JMeterThread: Thread finished: Thread Group 1-1
2019-02-02 11:08:29,160 ERROR o.a.j.e.JSR223PostProcessor: Problem in JSR223 script, JSR223 PostProcessor
javax.script.ScriptException: java.lang.NumberFormatException: For input string: "

这次它 "sees" 我想处理的字符串，但处理它们时似乎遇到了一些问题。对于我从其他 2 个包含不同字符串的响应中获得的其他 2 个变量，我又得到 2 个类似的错误（我发出 3 个请求并获得 3 个响应，每个响应包含不同的 body 字符串）。只是 "For input string" 之后的值不同。

Answer 1

如果您的回复中只有一个匹配项，请使用此代码粘贴到 JSR223 PostProcessor 中：

def csv = new File("my.csv")
csv << vars.get("foo") << System.getProperty("line.separator")

Answer 2

为了你的第一篇"code"
```
def csv = new File("my.csv")
1.upto(vars.get("foo_matchNr") as int, {
    csv << vars.get("foo_$it") << System.getProperty("line.separator")  
})
```
错误提示 ${foo_matchNr} 变量不存在，使用 Debug Sampler and View Results Tree 侦听器组合仔细检查它是否存在并且具有数值。

你的第二段代码：

def csv = new File("my.csv")
1.upto(vars.get("foo") as int, {
    csv << vars.get("foo_$it") << System.getProperty("line.separator")  
})

错误提示它无法投射此行：

   eyJhbRciOiRRRzI1RiIsInR5cCI6IkpXVCJ9.eyJ1c2RybmRtZSI6IlRlcmhhdCIsInR1aWQiOiJRZXJoYXQiLRJyb2xlRjoibW9iaWxlRRRwcCIsImVtYWlsIjoidGVzdEB0ZXN0LmNvbSIsImlkIjoiU2RyaGF0IiwiaWR0IjoxRRR5MDU5OTUxLCJleRRiOjE1NRkwNzQzRRR9.RRzm3VvioZ_iR-v5EGSSfYJLf0d9aZ-9R-RP4UbER04

到 Integer。我的期望是您需要将代码更改为：

new File("my.csv") << vars.get("foo") << System.getProperty("line.separator")

如果上述代码不会产生您正在寻找的内容 - 使用上述调试采样器的输出更新您的问题，并指出您想要存储哪些变量以及如何存储。

查看 The Groovy Templates Cheat Sheet for JMeter 文章以开始使用 Groovy 脚本。

一般我会推荐使用 Sample Variables property in order to store generated JMeter variables into the .jtl results file. If you want the output to go into a separate file - consider using Flexible File Writer

使用 JMeter，如何从 API 响应的 body 中提取字符串并将其保存到 csv 文件？

Using JMeter, how can I extract a string from the body of a response of an API and save it to a csv file?

groovy

jmeter

performance-testing

load-testing

beanshell