Question

我今天写信给社区，因为我在尝试访问API提供的对象时遇到了一些困惑。

使用的API：

使用Cloudflare的v4 API：适用的文档可在https://api.cloudflare.com/#user-level-firewall-access-rule-list-access-rules

概念

我在访问API时会收到与myObject相同的对象，但要确保我们了解了我可以在下面访问它的源代码。

具有漂亮格式的对象

{
  "result": [{
    "id": "e9a821b6379bd22539226a4cc6956144",
    "mode": "challenge",
    "allowed_modes": ["block", "challenge", "whitelist", "js_challenge"],
    "status": "active",
    "notes": "BY API",
    "scope": {
      "id": "981969ce21909a61b62905c585ec9aaa",
      "email": "user@example.com",
      "type": "user"
    },
    "configuration": {
      "value": "AD",
      "target": "country"
    },
    "created_on": "2017-08-06T17:05:19.126546Z",
    "modified_on": "2017-08-06T17:05:19.126546Z"
  }],
  "result_info": {
    "page": 1,
    "per_page": 1,
    "total_pages": 251,
    "count": 1,
    "total_count": 251
  },
  "success": true,
  "errors": [],
  "messages": []
}

下面的代码会返回没有问题的数字251，这是预期的。

var myObject = {"result":[{"id":"e9a821b6379bd22539226a4cc6956144","mode":"challenge","allowed_modes":["block","challenge","whitelist","js_challenge"],"status":"active","notes":"BY API","scope":{"id":"981969ce21909a61b62905c585ec9aaa","email":"user@example.com","type":"user"},"configuration":{"value":"AD","target":"country"},"created_on":"2017-08-06T17:05:19.126546Z","modified_on":"2017-08-06T17:05:19.126546Z"}],"result_info":{"page":1,"per_page":1,"total_pages":251,"count":1,"total_count":251},"success":true,"errors":[],"messages":[]}

console.log(myObject["result_info"]["total_pages"])

实际使用：

此脚本在节点中运行，配置模块包含API密钥和资料（由于显而易见的原因，它们不应公开）。

// Import required modules
var request = require('request');
var config = require('./config');


// Setup account details and site details (to edit these variables edit config.js)
var accountemail = config.accountemail;
var globalapikey = config.globalapikey;


// Setup other needed variables
var userfirewallruleids = []; // Store the IDs of each firewall rule in this array
var currentpage = 1;
var pagecount = 0;

// Get the page count (doing the first request twice is less efficient - refactor this in the future)


// Configure Headers (pretend to be CURL for now)
var headers = {
  'User-Agent': 'curl/7.47.0',
  'Content-Type': 'application/json',
  'X-Auth-Email': accountemail,
  'X-Auth-Key': globalapikey,
}

// Configure Request
var options = {
  url: 'https://api.cloudflare.com/client/v4/user/firewall/access_rules/rules?mode=challenge&configuration_target=country&page=1&per_page=1&order=mode&direction=desc&match=all',
  method: 'GET',
  headers: headers
}

// Do The Request (in production you can remove the console.log lines or comment it out - by default it'll return the entire response good or bad so you can see what went well or wrong)
request(options, function(error, response, body) {
  if (!error && response.statusCode == 200) {
    console.log(body["result_info"]["total_pages"]);
  } else {
    console.log(body);
  }
})

然而，与运行console.log(body["result_info"]["total_pages"]);的概念代码不同，将返回错误。

/Documents/Coding/cloudflare-scripts/remove-user-level-firewall-rules.js:44
 console.log(body["result_info"]["total_pages"]);

 ^

TypeError: Cannot read property 'total_pages' of undefined
 at Request._callback (/Users/nathanielsuchy/Documents/Coding/cloudflare-scripts/remove-user-level-firewall-rules.js:44:36)
 at Request.self.callback (/Users/nathanielsuchy/node_modules/request/request.js:188:22)
 at emitTwo (events.js:125:13)
 at Request.emit (events.js:213:7)
 at Request.<anonymous> (/Users/nathanielsuchy/node_modules/request/request.js:1171:10)
 at emitOne (events.js:115:13)
 at Request.emit (events.js:210:7)
 at IncomingMessage.<anonymous> (/Users/nathanielsuchy/node_modules/request/request.js:1091:12)
 at Object.onceWrapper (events.js:314:30)
 at emitNone (events.js:110:20)

我应该如何修复此脚本，以便直接从API的对象输出中访问页数？

Answer 1

在深入探讨这个问题后，感谢其他答案和评论，我找到了解决方案。

虽然JSON解析的示例代码有点偏差并且仍然导致错误，但在对JSON解析进行了一些研究之后，我找到了一个解决方案，编写以下代码给了我所需的信息。

console.log(JSON.parse(body)["result_info"]["total_pages"]);

主要的是属性括号表示法需要在JSON解析函数之外。

感谢所有在此提供帮助并帮助我提出此解决方案的人。

Answer 2

在访问JSON对象之前需要对其进行解析。

myObject = JSON.parse(body); console.log(myObject["child"]["nested child"]);

如何从RESTful API访问对象的此属性？

2 个答案: