javascript - cheerio each() 函数行为异常

Question

我有一个代码，可以对特定页面进行网络废弃。我使用 puppeteer+cheerio 来做到这一点。在我的笔记本电脑上代码完美运行。但是在将它部署到 VDS 之后，cheerio each() 选择器开始奇怪地工作。 (但它在我的笔记本电脑上仍然可以正常工作)。问题是在 VDS 上发生以下错误:

(node:28544) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'trim' of undefined at Node. (/home/ubuntu/handbot/liveMonitoring.js:211:82) at initialize.exports.each (/home/ubuntu/handbot/node_modules/cheerio/lib/api/traversing.js:300:24) at Node. (/home/ubuntu/handbot/liveMonitoring.js:182:29) at initialize.exports.each (/home/ubuntu/handbot/node_modules/cheerio/lib/api/traversing.js:300:24) at liveMonitoring (/home/ubuntu/handbot/liveMonitoring.js:175:28) at process._tickCallback (internal/process/next_tick.js:68:7) (node:28544) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1) (node:28544) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

最有趣的一点是有时错误会消失(似乎没有发生错误的模式)。我试图通过重新安装 node js 来解决这个问题，但它没有用。问题不在我的代码中(因为它可以在我的笔记本电脑上运行，有时甚至可以在 vds 上运行)。我认为导出 each() 函数有些问题。由于错误消息，

中发生了一些错误

/home/ubuntu/handbot/node_modules/cheerio/lib/api/traversing.js:300:24

traversing.js的代码(298-302行):

`

exports.each = function(fn) {
     var i = 0, len = this.length;
     while (i < len && fn.call(this[i], i, 
     this[i]) !== false) ++i;
     return this;
};

导致错误的代码:

const page = await browser.newPage();
await page.goto(url, {timeout:0}).catch((err)=> { console.log(err)});

await page.setRequestInterception(true);

page.on('request', req => {

    if(['image', 'stylesheet', 'font'].indexOf(req.resourceType()) !== -1)
        req.abort();
    else
        req.continue();

    });

 let content = await page.content();
 let $ = cheerio.load(content);



 let gameContent=$('#games_content').children('div').children('div');



 gameContent.children().each(function(i, elem1){

     let league=$(elem1).children('.greenBack').children('.c-events__name').children('a').text().trim();

     $(this).children().each(function(j, elem2){

         if(j!==0) {

             let currentInfo = {};
             currentInfo['league'] = league;

             let shortCut = $(elem2).children('.c-events__item_game').children('.c-events-scoreboard').children();
             let mainInfo = shortCut.first();

             currentInfo['link'] = mainInfo.children("a").attr("href");
             let teams = mainInfo.children("a").children("span").attr("title").trim().split("—");
             currentInfo['team1'] = teams[0].trim();
             currentInfo['team2'] = teams[1].trim();

             let shortCutForTotal = $(elem2).children('.c-events__item_game').children('.c-bets');

         }
     });
 });

提前致谢!`

Answer 1

通过更改这些代码行解决了问题:

page.on('request', req => {

 if(['image', 'stylesheet', 'font'].indexOf(req.resourceType()) !== -1)       
   req.abort();
 else 
   req.continue();

})

有以下几个:

page.on('request', interceptedRequest => {

     if (interceptedRequest.url().endsWith('.png') || interceptedRequest.url().endsWith('.jpg') || interceptedRequest.url().endsWith('.css'))

         interceptedRequest.abort();
     else

         interceptedRequest.continue();
});

并在上面的代码行之后放置 await page.goto(url);。

然后添加一个选项 waitUntil:'networkidle0' 到 page.goto(url)