在 Postman 中使用 JS Lodash 提取嵌套的 JSON 数组响应对象

Question

我想学习如何使用 Lodash 从 JSON 响应中提取变量，因为在其他 Postman 问题中解释的传统方法并没有像我以前在 Jmeter 中使用 json 路径那样解释一个简单的方法。

我需要将以下 json 路径转换为 ​​Lodash 表达式，该表达式返回与此 JSON 路径相同的值

1. FlightSegmentsItinerary[*].Flights[*].Key 
2. $..Flights[*].Key
3. Travelers[*].[?(@.TypeCode == "INF")].FirstName (returns the name of the passangers whose type code are == "INF")

JSON 响应：

 {
"Travelers": [
    {
        "TypeCode": "ADT",
        "FirstName": "FULANO",
        "Surname": "LAZARO",
        "Key": "1.1"
    },
    {
        "TypeCode": "INF",
        "FirstName": "MENGANO",
        "Surname": "XULO",
        "Key": "2.2"
    }
],
"FlightSegmentsItinerary": [
    {
        "Flights": [
            {
                "Key": "1"
            },
            {
                "Key": "2"
            }
        ]
    }
]
}

到目前为止，我能够使用以下方法提取旅行者密钥 (Travelers[*].Key)：

var jsonData = pm.response.json();    
var travelerKeys = _.map(jsonData.Travelers, 'Key');
console.log("travelerKeys: " + travelerKeys);
Output: travelerKeys: 1.1,2.2

如你所见，JSON 路径：

旅行者[*].Key

在 Lodash 中看起来像这样：

var travelerKeys = _.map(jsonData.Travelers, 'Key');

对于这种情况。

Answer 1

var jsonData = {
  "Travelers": [{
      "TypeCode": "ADT",
      "FirstName": "FULANO",
      "Surname": "LAZARO",
      "Key": "1.1"
    },
    {
      "TypeCode": "INF",
      "FirstName": "MENGANO",
      "Surname": "XULO",
      "Key": "2.2"
    }
  ],
  "FlightSegmentsItinerary": [{
    "Flights": [{
        "Key": "1"
      },
      {
        "Key": "2"
      }
    ]
  }]
}

// 1. FlightSegmentsItinerary[*].Flights[*].Key 
console.log( _(jsonData.FlightSegmentsItinerary).flatMap('Flights').map('Key') ) 

//2. $..Flights[*].Key
console.log( _.chain(jsonData).values().flatten().find('Flights').values().flatten().map('Key') )

//3. Travelers[*].[?(@.TypeCode == "INF")].FirstName (returns the name of the passangers whose type code are == "INF")
console.log( _(jsonData.Travelers).filter(['TypeCode', 'INF']).map('FirstName') )

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.11/lodash.min.js"></script>

---

另一种选择可能是尝试 JavaScript 库，例如 https://github.com/dchester/jsonpath

var jsonData = {
  "Travelers": [{
      "TypeCode": "ADT",
      "FirstName": "FULANO",
      "Surname": "LAZARO",
      "Key": "1.1"
    },
    {
      "TypeCode": "INF",
      "FirstName": "MENGANO",
      "Surname": "XULO",
      "Key": "2.2"
    }
  ],
  "FlightSegmentsItinerary": [{
    "Flights": [{
        "Key": "1"
      },
      {
        "Key": "2"
      }
    ]
  }]
}

console.log(jsonpath.query(jsonData, '$.FlightSegmentsItinerary[*].Flights[*].Key'))

console.log(jsonpath.query(jsonData, '$..Flights[*].Key'))

console.log(jsonpath.query(jsonData, '$.Travelers..[?(@.TypeCode == "INF")].FirstName')) 

<script src="https://cdn.jsdelivr.net/npm/jsonpath@1.0.2/jsonpath.min.js"></script>

由于Postman不支持fetch和XMLHttpRequest，所以可以将jsonpath.min.js文件内容保存在环境变量中，然后eval(pm.environment.get('jsonpath'));在使用前按照描述 https://community.getpostman.com/t/adding-external-libraries-to-postman/1971/4

Answer 2

您必须使用require 函数告诉 Postman 您要使用哪个沙盒模块（请参阅下面的代码）。你得到的错误与邮递员有一些问题，他们中的少数人不是Here they are talking 和Here is the postman issue tracker

我尝试并为我工作的代码

const moment = require('lodash');
var keys = _.chain(obj.Travelers)
        .map("Key")
        .flatten()
        .unique()
        .value();
console.log(keys);

输出

Array:[]
0 : "1.1"
1 : "2.2"

更多细节可以看
Postman Sandbox API reference
postman-and-lodash-the-perfect-partnership