删除 cookie：如何获取其路径（和域）？

Question

各种文章和SO answers建议通过JS删除cookie应该是这样的：

document.cookie = cookieName + '=; expires=Thu, 01 Jan 1970 00:00:01 GMT;';

或者如果我们需要指定域/路径，像这样：

document.cookie = cookieName + "=" +
    (path   ? `;path=${path}` : "") +
    (domain ? `;domain=${domain}` : "") +
    ";expires=Thu, 01 Jan 1970 00:00:01 GMT";

现在，在非根位置（如https://classic.tiddlywiki.com/upgrade/）发生了更复杂的情况。如果你打开它并在控制台输入document.cookie，你会得到一个值（没有指定domain、path或expires）：

TiddlyWikiClassicOptions=chkRegExpSearch:%22false%22 chkCaseSensitiveSearch:%22false%22 chkIncrementalSearch:%22true%22 chkAnimate:%22true%22 chkSaveBackups:%22true%22 chkAutoSave:%22false%22 chkGenerateAnRssFeed:%22false%22 chkSaveEmptyTemplate:%22false%22 chkOpenInNewWindow:%22true%22 chkToggleLinks:%22false%22 chkHttpReadOnly:%22true%22 chkForceMinorUpdate:%22false%22 chkConfirmDelete:%22true%22 chkInsertTabs:%22false%22 chkUsePreForStorage:%22true%22 chkDisplayInstrumentation:%22false%22 chkRemoveExtraMarkers:%22false%22 txtBackupFolder:%22%22 txtEditorFocus:%22text%22 txtMainTab:%22Timeline%22 txtMoreTab:%22moreTabAll%22 txtMaxEditRows:%2230%22 txtFileSystemCharSet:%22UTF-8%22 txtTheme:%22%22 txtUserName:%22YourName%22

在控制台中写入

document.cookie = 'TiddlyWikiClassicOptions=; expires=Thu, 01 Jan 1970 00:00:01 GMT;';

不会删除 cookie（或更改其值）（document.cookie 给出相同的结果）。此外，写作

document.cookie = 'TiddlyWikiClassicOptions=lalala';

不会更改现有的 cookie，而是添加另一个具有相同名称的 cookie：

TiddlyWikiClassicOptions=lalala; TiddlyWikiClassicOptions=chkRegExpSearch:%22false%22 chkCaseSensitiveSearch:%22false%22 chkIncrementalSearch:%22true%22 chkAnimate:%22true%22 chkSaveBackups:%22true%22 chkAutoSave:%22false%22 chkGenerateAnRssFeed:%22false%22 chkSaveEmptyTemplate:%22false%22 chkOpenInNewWindow:%22true%22 chkToggleLinks:%22false%22 chkHttpReadOnly:%22true%22 chkForceMinorUpdate:%22false%22 chkConfirmDelete:%22true%22 chkInsertTabs:%22false%22 chkUsePreForStorage:%22true%22 chkDisplayInstrumentation:%22false%22 chkRemoveExtraMarkers:%22false%22 txtBackupFolder:%22%22 txtEditorFocus:%22text%22 txtMainTab:%22Timeline%22 txtMoreTab:%22moreTabAll%22 txtMaxEditRows:%2230%22 txtFileSystemCharSet:%22UTF-8%22 txtTheme:%22%22 txtUserName:%22YourName%22

这就是我在干净的 Chrome 中得到的。我也试过在 Vivaldi 中安装 HTML5 Storage Manager All in One（Chrome 扩展），它显示相同，除了存在 2 个 cookie 的情况：而控制台给出与上面相同的行（在document.cookie） , 扩展显示

https://classic.tiddlywiki.com/ 不会发生这种情况（删除/编辑按预期工作）。

现在，我认为要删除初始 cookie，我必须这样做

document.cookie = 'TiddlyWikiClassicOptions=; path=/; expires=Thu, 01 Jan 1970 00:00:01 GMT;';

如果我添加了lalala，我也必须这样做

document.cookie = 'TiddlyWikiClassicOptions=; expires=Thu, 01 Jan 1970 00:00:01 GMT;';

删除第二个。

我想知道，我如何确定应该使用哪条路径？ document.cookie 似乎对每个 cookie 的“范围”保持沉默。或者这是设计引入的东西，我总是必须知道哪个 cookie 分配给哪个路径？

PS 我看到一篇帖子让我觉得域 (it's in Russian) 也存在同样的问题，所以我想知道如何让域也与 cookie 关联。

Answer 1

如果您不知道 cookie 的（子）域和/或路径，请尝试使所有组合过期。

var hostname = window.location.hostname;
var pathname = window.location.pathname;
var i = -1;
do {
  var domain = hostname.substr(i+1);
  var j = 0;
  do {
    var path = pathname.substr(0,j+1);
    var cookie = 'TiddlyWikiClassicOptions=; path='+path+'; domain='+domain+'; expires=Thu, 01 Jan 1970 00:00:01 GMT;';
    console.log(cookie);
    // stacksnippets throws an exception... uncomment to set cookie.
    //document.cookie = cookie;
  } while ((j = pathname.indexOf('/', j+1)) != -1)
} while ((i = hostname.indexOf('.', i+1)) < hostname.lastIndexOf('.'));

Answer 2

这是我对 dana 想法的实现（删除每个路径+域对的 cookie）：

function deleteCookieFromAllScopes(cookieName)
{
    var domainParts = window.location.hostname.split('.').reverse();
    var topLevelDomain = domainParts.shift();
    var domains = [];
    for(let domainPart of domainParts)
    {
        let prevDomain = domains.slice(-1)[0] || topLevelDomain;
        domains.push(domainPart + '.' + prevDomain);
    }

    var path = window.location.pathname;
    var paths = ['/'], pathLength = 1, nextSlashPosition;
    while( (nextSlashPosition = path.indexOf('/', pathLength)) != -1 )
    {
        pathLength = nextSlashPosition + 1;
        paths.push(path.substr(0, pathLength));
    }

    for(let path of paths)
        for(let domain of domains)
            document.cookie = `${cookieName}=; path=${path}; domain=${domain}; expires=Thu, 01 Jan 1970 00:00:01 GMT;`;
}

它不再是毫无疑问的，但我认为更具可读性。欢迎提出改进建议。

以下是对通过file: 方案或localhost 域打开的页面的特殊cookie 情况的修改：

function deleteCookieFromAllPaths(cookieName)
{
    var path = window.location.pathname;
    var paths = ['/'], pathLength = 1, nextSlashPosition;
    while( (nextSlashPosition = path.indexOf('/', pathLength)) != -1 )
    {
        pathLength = nextSlashPosition + 1;
        paths.push(path.substr(0, pathLength));
    }

    for(let path of paths)
        document.cookie = `${cookieName}=; path=${path}; expires=Thu, 01 Jan 1970 00:00:01 GMT;`;
}