如何从JSon中提取多个相关变量

Question

我必须从JMeter的响应（是json）中提取多个相关变量。下面列出了部分响应：

[
  {
    "data": {
      "id": "efaa6876-7a8d-4723-9d85-1ed99e822f06",
      "type": "courses",
      "attributes": {
        "created-at": "2019-02-07T16:38:50.735Z",
        "contents-count": 267,
        "units": [
          {
            "id": "31b5fcb1-24ee-441e-a0ee-ca859fc9a89d",
            "position": null,
            "progress": 0,
            "completed": false,
            "show_name": false,
            "node_id": "1",
            "children": [
              {
                "id": "b8ed75a3-0390-4273-82c3-03ee6eba729c",
                "position": null,
                "image": null,
                "progress": 0,
                "completed": false,
                "show_name": true,
                "node_id": "2",
                "children": [],
                "contents": [
                  {
                    "id": "fa1bdc2f-4330-425c-9c10-3734d07125aa",
                    "link": {
                      "url": "#",
                      "target": "_blank",
                      "class": "learning-object-link",
                      "data": {
                        "id": "fa1bdc2f-4330-425c-9c10-3734d07125aa",
                        "user-role": "teacher",
                        "open-method-tablet": "newtab",
                        "open-method-desktop": "modal",
                        "content-open-method": null,
                        "modal-size-method": "fully_responsive",
                        "fixed-width": null,
                        "fixed-height": null,
                        "aspect-ratio": null
                      }
                    },
                    "is_work": false,
                    "is_fun": false,
                    "completed": false,
                    "total_activities": 2,
                    "completed_activities": 0,
                    "progress": 0,
                    "updated_at": false,
                    "attempts": 0,
                    "duration": null
                  },
                  {
                    "id": "ceceabfd-5151-4656-af5d-3392c5a4c04c",
                      "link": {
                      "url": "#",
                      "target": "_blank",
                      "class": "learning-object-link",
                      "data": {
                        "id": "ceceabfd-5151-4656-af5d-3392c5a4c04c",
                        "user-role": "teacher",
                        "open-method-tablet": "newtab",
                        "open-method-desktop": "modal",
                        "content-open-method": null,
                        "modal-size-method": "fully_responsive",
                        "fixed-width": null,
                        "fixed-height": null,
                        "aspect-ratio": null
                      }
                    },
                    "is_work": false,
                    "is_fun": false,
                    "completed": false,
                    "total_activities": 2,
                    "completed_activities": 0,
                    "progress": 0,
                    "updated_at": false,
                    "attempts": 0,
                    "duration": null
                  }
                ]
              },
              {
                "id": "60639cbd-f872-492d-b8e9-db83f8789fcf",
                "position": null,
                "image": null,
                "progress": 0,
                "completed": false,
                "show_name": true,
                "node_id": "3",
                "children": [],
                "contents": [
                  {
                    "id": "1825f834-7099-4bb4-b7a2-fc634faffc86",
                      "link": {
                      "url": "#",
                      "target": "_blank",
                      "class": "learning-object-link",
                      "data": {
                        "id": "1825f834-7099-4bb4-b7a2-fc634faffc86",
                        "user-role": "teacher",
                        "open-method-tablet": "newtab",
                        "open-method-desktop": "modal",
                        "content-open-method": null,
                        "modal-size-method": "fully_responsive",
                        "fixed-width": null,
                        "fixed-height": null,
                        "aspect-ratio": null
                      }
                    },

要继续下一个请求，我必须提取单元ID（例如31b5fcb1-24ee-441e-a0ee-ca859fc9a89d），儿童ID（例如b8ed75a3-0390-4273-82c3-03ee6eba729c）和内容ID（例如fa1bdc2f- 4330-425c-9c10-3734d07125aa）。有几个单位，每个单位有几个孩子，每个孩子有几个内容。每个内容ID仅匹配一个孩子ID，每个孩子ID仅匹配一个单位ID。 ID必须随机选择。

我尝试从响应中提取所有ID并随机使用它们，但是这种方式行不通。

Answer 1

要仅提取单元ID，可以使用以下JSON路径表达式：

$..data.attributes.units[?(@.id)].id

也可以使用JMeter JSON提取器提取单位ID的随机值：