如何在JMeter中用JSR223后置处理器复用Modalities构造请求JSON

问题说明 #

在JMeter中发送请求后，收到的JSON响应里包含数量可变的modalities数组，需要在后续请求的JSON体中完整复用这些modalities数据。已编写部分Groovy代码，但不知道如何构造符合要求的请求JSON结构。

响应示例 #

{"studyDTO": {"studyId": 191,"studyCode": "test_ispptest2"},"sites": [],"subjects": [],"visits": [],"sftpLocations": [],"dicomLocations": [],"fileSystemLocations": [],"rawFileSystemLocations": [],"states": null,"modalities": [{"studyId": 191,"submitValue": "ct","displayValue": "Conventional CT","orderOfDisplay": 30},{"studyId": 191,"submitValue": "multi_slice_spiral_ct","displayValue": "Multi-Slice Spiral CT","orderOfDisplay": 50},{"studyId": 191,"submitValue": "dxa","displayValue": "DXA","orderOfDisplay": 60},{"studyId": 191,"submitValue": "mri","displayValue": "MRI","orderOfDisplay": 100},{"studyId": 191,"submitValue": "unknown","displayValue": "Unknown","orderOfDisplay": 240}],"examDates": [],"series": null,"transferType": null,"customFolder": false,"customFile": false,"folderStructure": null,"fileStructure": null,"allSites": true,"allSubjects": true,"allVisits": true,"allStates": false,"allExamDates": true,"allModalities": false,"allSeries": false,"softEditOverride": false,"includePS": false,"includeSR": false,"includeRTStruct": false,"dicomTemplate": null,"errorMessage": null,"successMessage": null}

目标请求示例 #

{"studyDTO": {"studyId": 191,"studyCode": "test_ispptest2"},"allVisits": true,"modalities": [{"studyId": 191,"submitValue": "ct","displayValue": "Conventional CT","orderOfDisplay": 30},{"studyId": 191,"submitValue": "multi_slice_spiral_ct","displayValue": "Multi-Slice Spiral CT","orderOfDisplay": 50},{"studyId": 191,"submitValue": "dxa","displayValue": "DXA","orderOfDisplay": 60},{"studyId": 191,"submitValue": "mri","displayValue": "MRI","orderOfDisplay": 100},{"studyId": 191,"submitValue": "unknown","displayValue": "Unknown","orderOfDisplay": 240}],"includePS": null}

现有代码 #

import groovy.json.JsonSlurper
def jsonString = prev.getResponseDataAsString();
def jsonConvert = new JsonSlurper();
def object = jsonConvert.parseText(jsonString);
def modalityS = object.modalities.size().toString();
def modalitySize = modalityS?.isInteger() ? modalityS.toInteger() : null
for (int i = 0; i < modalitySize ; i++) {
    def modalityOrderOfDisplay = object.modalities[i].orderOfDisplay;
    def modalSubmitValue = object.modalities[i].submitValue;
    def modalDisplayValue = object.modalities[i].displayValue;
    log.info('-----------------------'+modalityOrderOfDisplay);
    log.info('-----------------------'+modalSubmitValue);
    log.info('-----------------------'+modalDisplayValue);
}

解决方案 #

你现有的代码仅遍历打印了modalities的字段，没有组装成完整的请求JSON结构。可以通过Groovy的JsonBuilder直接构造符合要求的JSON字符串，并存储到JMeter变量中，供后续请求使用：

import groovy.json.JsonSlurper
import groovy.json.JsonBuilder

// 解析响应的JSON数据
def responseJson = prev.getResponseDataAsString()
def slurper = new JsonSlurper()
def parsedData = slurper.parseText(responseJson)

// 构造目标请求的JSON结构，直接复用响应中的所需字段
def requestBody = [
    studyDTO: parsedData.studyDTO,
    allVisits: true,
    modalities: parsedData.modalities,
    includePS: null
]

// 将构造好的JSON转为字符串，存入JMeter变量
def builder = new JsonBuilder(requestBody)
vars.put("targetRequestJson", builder.toString())

使用方法 #

在后续请求的Body Data中，直接引用变量${targetRequestJson}即可，JMeter会自动替换为构造好的JSON内容。

内容的提问来源于stack exchange，提问作者MAX GRIMM