CasperJS跳过超时

Question

我的casperjs测试中有一个页面有图像,我不要等到这个页面加载到下一步.我该怎么做 ？我试过这种方式

var casper = require("casper").create({
   onStepTimeout: function() {
                        this.echo("TIMEOUT" + this.requestUrl,"RED_BAR");
   // Some skip page controlling code 
   },
);
var timeout = ~~casper.cli.get(0);

casper.start("http://127.0.0.1/index2.php", function () {
    this.echo("FIRST GOOD PAGE", "GREEN_BAR");
    casper.options.stepTimeout = timeout;
});

casper.thenOpen("http://127.0.0.1/slowpage.php", function() {
        this.echo("SECOND PAGE LOADED - I want to be called even  have received Timeout!", "GREEN_BAR");
});

casper.then(function() {
    this.echo("THEN!", "GREEN_BAR"); 
});

但它只是调用onStepTimeout直到slopage.php被加载.

Answer 1

您可以添加request.abort();一个casper步骤来结束该步骤并继续下一步:

casper.then(function() {
  request.abort();
  this.echo('You will never see me');
});

casper.then(function() {
  this.echo('I execute next');
});

您还可以根据open要求检查是否要中止.此函数将检查匹配的URL,然后在打开之前中止,并将返回http状态代码:

casper.on('page.resource.requested', function(requestData, request) {
    if (requestData.url.indexOf('slowpage.php') !== -1) {
        request.abort();
    }
});

您可以更改waitTimeout和stepTimeout设置.另外,在pageSettings你可以使casper不加载图像.例:

var casper = require('casper').create ({
    waitTimeout: 10000,
    stepTimeout: 10000,
    verbose: true,
    viewportSize: {
      width: 1400,
      height: 768
    },
    pageSettings: {
      "userAgent": 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.10 (KHTML, like Gecko) Chrome/23.0.1262.0 Safari/537.10',
      "loadImages": false,
      "loadPlugins": false,         
      "webSecurityEnabled": false,
      "ignoreSslErrors": true
    },
    onWaitTimeout: function() {
        //throw new Error
    },
    onStepTimeout: function() {
        //throw new Error
    }
});

您可以使用casper waitFor等待页面完全加载.只是return true.它甚至有自己的timeout功能.所以你可以这样做:

casper.waitFor(function check() {
    casper.thenOpen("http://127.0.0.1/slowpage.php", function() {
        //+++ casper will wait until this returns true to move forward. 
        //+++ The default timeout is set to 5000ms
        this.evaluate(function() {
          //checks for element exist
          if (document.getElementById('someElement')) {
            console.log('Im loaded!');
            return true;
          }
        });
    });   
}, function then() {    // step to execute when function check() is ok
    //+++ executes ONLY after the 'casper.thenOpen' returns true.
    this.echo("THEN!", "GREEN_BAR");
}, function timeout() { // step to execute if check has failed
    //+++ code for on timeout.  This is different than onStepTimeOut.
},1000);// custom timeOut setting.

Answer 2

实际上,在某些情况下,stepTimeout由于连接问题,CasperJS的步骤偶尔会因超时(如果在设置中指定)而到期.默认行为是停止CasperJS this.die.如果要求不停止CasperJS,而是继续执行后续步骤,则应提供自定义onStepTimeout.不幸的是,request.abort在这种情况下没有定义,因为request只能在onResourceRequested处理程序内部访问(这就是为什么@Topher Ellis的答案有问题).换句话说,request.abort有助于防止发出新请求,但无法阻止正在进行的请求(并且可能会超时).对于这种情况,我使用以下代码:

var casper = require("casper").create(
{
  ...
  onStepTimeout: function(timeout, step)
  {
    this.echo('step timeout');
    this.clear();
    this.page.stop();
  }
});

希望这可以帮助.