selenium-webdriver 将函数数组作为参数传递给 executeScript

selenium-webdriver pass an array of functions as argument to executeScript

import webdriver from 'selenium-webdriver';

const driver = new webdriver.Builder()
              .withCapabilities(webdriver.Capabilities.chrome())
              .build();

driver.get('https://www.google.com');
let foo = function(rules) {
  rules.forEach(rule => {
    rule();
  });
}
let bar = function() { return 'bar' };
let baz = function() { return 'baz' };
driver.executeScript(foo, [bar, baz]).then(function(result) {
  console.log(result);
});

driver.quit();

它出错了

WebDriverError: unknown error: rule is not a function


let foo = function(rules) {
  return rules;
  // rules.forEach(rule => {
  //   rule();
  // });
}
let bar = function() { return 'bar' };
let baz = function() { return 'baz' };
driver.executeScript(foo, [bar, baz]).then(function(result) {
  console.log(result); // refer the log pasted below
});

看起来函数正在序列化 string

[ 'function bar() {\n  return \'bar\';\n}',
  'function baz() {\n  return \'baz\';\n}' ]

任何关于如何通过 array of functions as arguments 的指示都会有所帮助。

问题: 所有作为参数传递给函数的重要数据都将转换为字符串,因为这是从 selenium 驱动程序向浏览器注入内容的唯一方法。

Arguments must be a number, a boolean, a String, WebElement, or a List of any combination of the above.

解决方案 您可以将字符串转换为函数并使用 eval 或函数构造函数 new Function('...function body here...') 执行它。是的,这是非常糟糕的,但实际上,没有其他方法可以将重要数据从驱动程序传递到浏览器。实际上,当您调用此 driver.executeScript(foo, [], ...) 时,foo 函数也被转换为字符串并在浏览器中使用 eval 执行。

如果我是你,我会尝试寻找另一种无需将函数作为参数传递即可获得结果的方法。

您可以在以下位置阅读更多信息:https://selenium.googlecode.com/svn/trunk/docs/api/java/org/openqa/selenium/JavascriptExecutor.html

我想你可以使用 eval。请参阅下面的代码:

driver.get('https://www.google.com');
let foo = function(rules) {
    var results = [];
    rules.forEach(rule => {
        results.push(eval(rule));
    });
    return results;
}

let bar = "(function() { return ' message returned from bar' })()";
let baz = "(function() { return 'message returned from baz' })()";

driver.executeScript(foo, [bar, baz]).then(function(result) {
    console.log(result);
});

我找到了一个不同的解决方法,w/o 使用 eval 显式 ,但方式相似。

  1. 要注入的函数必须命名 函数
  2. 注入function.toString()作为<script>

    的内容
    function foo(rules) {
      var result = [];
      rules.forEach(rule => {
        result.push(rule());
      });
      return result;
    }
    function bar() { return 'bar' };
    function baz() { return 'baz' };
    
    function inject(content) {
      var script = document.createElement('script');
      script.innerHTML = content;
      document.head.appendChild(script);
    }
    let script = `${bar.toString()} ${baz.toString()} ${foo.toString()}`;
    
    driver.executeScript(inject, script);
    
  3. 然后执行想要的函数为

    driver.executeScript('return foo([bar, baz])').then(function(result) {
      // use the result
    });
    

完整示例

// example.js
import webdriver from 'selenium-webdriver';

const driver = new webdriver.Builder()
  .withCapabilities(webdriver.Capabilities.chrome())
  .build();

driver.get('https://www.google.com');

function foo(rules) {
  var result = [];
  rules.forEach(rule => {
    result.push(rule());
  });
  return result;
}
function bar() { return 'bar' };
function baz() { return 'baz' };

function inject(content) {
  var script = document.createElement('script');
  script.innerHTML = content;
  document.head.appendChild(script);
}
let script = `${bar.toString()} ${baz.toString()} ${foo.toString()}`;

driver.executeScript(inject, script);

driver.executeScript('return foo([bar, baz])').then(function(result) {
  console.log(result);
});

driver.quit();

> babel-node example.js

[ 'bar', 'baz' ]