问题描述
限时送ChatGPT账号..我正在编写一个 NodeJS 脚本,它通过 GET(使用来自 npm 的 request
)调用一堆 API,并将响应保存在一个 JSON 文件中.我正在使用 for
循环遍历 ID 以传递给 API,但我无法在呼叫突发之间设置延迟,因此我不会向 API 服务器发送垃圾邮件并使其生气我(速率限制).有人知道怎么做吗?
我当前的代码(没有任何延迟):
var fs = require('fs');var request = require('request');//遍历 IDfor(var i = 1; i <= 4; i++){(功能(一){callAPIs(i);//调用我们的 API})(一世);}函数调用APIs(id){//调用一些 API 并异步存储响应,例如:request.get("https://example/api/?id=" + id, (err, response, body) =>{如果(错误){抛出错误;}fs.writeFile("./result/" + id + '/' + id + '_example.json', body, function (err){如果(错误){抛出错误;}});});}
我正在寻找这种行为:
callAPIs(1);//开始对 ID# 1 的呼叫突发//稍等一会...callAPIs(2);//开始对 ID# 2 的呼叫突发//稍等一会...//等等
解决方案 你可以使用新的 ES6 的 async/await
(async() => {for(var i = 1; i <= 4; i++){console.log(`调用 API(${i})`)等待 callAPIs(i);console.log(`Done API(${i})`)}})();函数调用APIs(id){返回新的承诺(解决 => {//模拟你的网络请求延迟setTimeout(() => {//做你的网络成功处理函数或其他东西返回解决(1)}, 2 * 1000)});}
一个工作演示:https://runkit/5d05476405c94a/5d05476405c95c95c94054040404054054040404040540404054040404054040405404040403
I'm writing a NodeJS script that calls a bunch of APIs via GET (using request
from npm) and saves the responses in a JSON file. I'm using a for
to loop through IDs to pass to the APIs, but I'm having trouble putting in a delay between call bursts so I don't spam the API server and make it mad at me (rate limiting). Does anyone know how to do this?
My current code (without any delay):
var fs = require('fs');
var request = require('request');
// run through the IDs
for(var i = 1; i <= 4; i++)
{
(function(i)
{
callAPIs(i); // call our APIs
})(i);
}
function callAPIs(id)
{
// call some APIs and store the responses asynchronously, for example:
request.get("https://example/api/?id=" + id, (err, response, body) =>
{
if (err)
{throw err;}
fs.writeFile("./result/" + id + '/' + id + '_example.json', body, function (err)
{
if (err)
{throw err;}
});
});
}
I'm looking for this behavior:
callAPIs(1); // start a burst of calls for ID# 1
// wait a bit...
callAPIs(2); // start a burst of calls for ID# 2
// wait a bit...
// etc
解决方案
You can use the new ES6's async/await
(async () => {
for(var i = 1; i <= 4; i++)
{
console.log(`Calling API(${i})`)
await callAPIs(i);
console.log(`Done API(${i})`)
}
})();
function callAPIs(id)
{
return new Promise(resolve => {
// Simulating your network request delay
setTimeout(() => {
// Do your network success handler function or other stuff
return resolve(1)
}, 2 * 1000)
});
}
A working demo: https://runkit/5d054715c94464001a79259a/5d0547154028940013de9e3c
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