Prevent execution of a specific inline script tag

问题

I'm trying to write a script for Tampermonkey that prevents the execution of a specific inline script tag. The body of the page looks something like this

<body>
  <!-- the following script tag should be executed-->
  <script type="text/javascript">
    alert("I'm executed as normal")
  </script>
  <!-- the following script tag should NOT be executed-->
  <script type="text/javascript">
    alert("I should not be executed")
  </script>
  <!-- the following script tag should be executed-->
  <script type="text/javascript">
    alert("I'm executed as normal, too")
  </script>
</body>

I tried to remove the script tag using my Tampermonkey script, but if I run it at document-start or document-body the script tag does not exist yet. If I run it at document-end or document-idle the script tag I'd like to remove is run before my Tampermonkey script is executed.

How can I prevent execution of the script tag?

Note: The actual script tag that I'd like to prevent from executing contains window.location = 'redirect-url'. So it would also be sufficient to prevent the reload in this case.

Versions:

Chromium 65.0.3325.181
Tampermonkey 4.5

回答1:

Alternative version free of doc.write/XHR --

   (() => { 
          'use strict';
          let needle = '/window.location/';
          if ( needle === '' || needle === '{{1}}' ) {
              needle = '.?';
          } else if ( needle.slice(0,1) === '/' && needle.slice(-1) === '/' ) {
              needle = needle.slice(1,-1);
          } else {
              needle = needle.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
          }
          needle = new RegExp(needle);
          const jsnode = () => {
                        try {
                            const jss = document.querySelectorAll('script');
                            for (const js of jss) {
                                if (js.outerHTML.match(needle)) {
                                        js.remove();
                                }           
                            }
                        } catch { }
          };
          const observer = new MutationObserver(jsnode);
          observer.observe(document.documentElement, { childList: true, subtree: true });
})();

回答2:

Delete script tag on document-start (as suggested by wOxxOm):

(function() {
    'use strict';
    window.stop();
    const xhr = new XMLHttpRequest();
    xhr.open('GET', window.location.href);
    xhr.onload = () => {
        var html = xhr.responseText
        .replace(/<script\b[\s\S]*?<\/script>/g, s => {
            // check if script tag should be replaced/deleted
            if (s.includes('window.location')) {
                return '';
            } else {
                return s;
            }
        });
        document.open();
        document.write(html);
        document.close();
    };
    xhr.send();
})();

来源：https://stackoverflow.com/questions/50020880/prevent-execution-of-a-specific-inline-script-tag

标签

javascript

html

tampermonkey