Question

我需要为以下任务创建一个nodejs：

1) Get my public IP address.
2) Update my public IP Address on my freenom.com account, for my registered domain.

我有两个脚本分开工作。

1）获取我的公共IP（npm安装请求）：

'use strict';
var request = require('request');
request('http://api.ipify.org', function (error, response, body) {
  if (!error && response.statusCode == 200) {
    console.log(body);
  }
  else {
    console.log("Error "+response.statusCode);
  }
})

// This print my public IP correctly

2）更新我在freenom帐户中的IP（npm install -g freenom-dns）：

'use strict';
var user = "my@user_email.com";
var pass = "mypass";
var freenom = require("freenom-dns").init(user, pass);
freenom.dns.setRecord("myregistereddomain.com", "A", "12.12.12.12" , 3600)
                  .then(function(ret) {
                              console.log(ret)
                      })
                  .catch((err) => {
                      console.log(err);
                  });

// This update my new public IP on my freenom account as 12.12.12.12 correctly

我尝试声明一个全局变量，并尝试在我的第一个脚本（获取公共IP）上将其传递给“ body”函数返回，因为在此之后，请调用第二个脚本，并传递“ My_IP” var：

'use strict';

var My_IP = ""
var user = "my@user_email.com";
var pass = "mypass";

var freenom = require("freenom-dns").init(user, pass);
var request = require('request');

request('http://api.ipify.org', function (error, response, body) {
  if (!error && response.statusCode == 200) {
    console.log(body);
    My_IP = body;
  }
  else {
    console.log("Error "+response.statusCode);
  }
})

freenom.dns.setRecord("myregistereddomain.com", "A", My_IP , 3600)
                  .then(function(ret) {
                              console.log(ret)
                      })
                  .catch((err) => {
                      console.log(err);
                  });

但是My_IP的类型不是String变量。更新公共IP功能，仅允许将字符串值用作参数。调用此函数时，如何获得“ body”值？

Answer 1

My_IP似乎是字符串变量。正义值是空的

您应检查执行顺序。 request()是异步任务
将通过回调函数返回数据

这是执行顺序

My_IP = ''
request(..., callback)
freenom.dns.setRecord(..., My_IP) // My_IP is still empty
callback() // My_IP is update here

您可以这样实现（或使用Promise，Async函数等。）

request('http://api.ipify.org', function (error, response, body) {
  if (!error && response.statusCode == 200) {
    console.log(body);
    My_IP = body;
    handler() // After My_IP was updated
  }
  else {
    console.log("Error "+response.statusCode);
  }
})

function handler () {
  freenom.dns.setRecord("myregistereddomain.com", "A", My_IP , 3600)
    .then(function(ret) {
      console.log(ret)
    })
    .catch((err) => {
      console.log(err);
    });
}

Answer 2

IMO看起来请求返回了Promise，并在请求获得响应之前调用setRecord尝试：

'use strict';
const freenom = require("freenom-dns").init(user, pass);
const request = require('request');

let My_IP = "";
let user = "my@user_email.com";
let pass = "mypass";

const createRequest = () => {
    request('http://api.ipify.org', function (error, response, body) {
        if (!error && response.statusCode == 200) {
            console.log(body);
            My_IP = body;
            setDns();
        }
        else {
            console.log("Error "+response.statusCode);
        }
    })
};

const setDns = () => {
    freenom.dns.setRecord("myregistereddomain.com", "A", My_IP , 3600)
        .then(function(ret) {
            console.log(ret)
        })
        .catch((err) => {
            console.log(err);
        });
};

调用此函数时如何获得返回值？

2 个答案: