Node.js：获取已安装的npm包的（绝对）根路径

问题描述

我正在寻找一种通用方法来获取Node.js中已安装的npm包的（绝对）根路径。

I'm looking for an universal way to get the (absolute) root path of an installed npm package in Node.js.

我知道 require.resolve ，但这会给出我是入口点（主模块的路径）而不是包的根路径。

I know about require.resolve, but that will give me the entry point (path to the main module) rather than the root path of the package.

取 bootstrap-sass 作为一个例子。假设它在本地安装在项目文件夹 C：\ dev \ my-project 中。然后我要找的是 C：\ dev \ my-project \ node_modules \ bootstrap-sass 。 require.resolve（'bootstrap-sass'）将返回 C：\dev \ my-project \ node_modules \ bootstrap-sass \\ \\ assets\javascripts\bootstrap.js 。

Take bootstrap-sass as an example. Say it's installed locally in a project folder C:\dev\my-project. Then what I'm looking for is C:\dev\my-project\node_modules\bootstrap-sass. require.resolve('bootstrap-sass') will return C:\dev\my-project\node_modules\bootstrap-sass\assets\javascripts\bootstrap.js.

我可以想到几种方法如何获取包的根路径：

I can think of several methods how to get the package's root path:

var packageRoot = path.resolve('node_modules/bootstrap-sass');
console.log(packageRoot);

这对于本地安装在 node_modules 文件夹。但是，如果我在子文件夹中，我需要解析 ../ node_modules / bootstrap-sass ，并且使用更多嵌套文件夹会更复杂。此外，这对全局安装的模块不起作用。

This will work fine for packages installed locally in node_modules folder. However, if I'm in a subfolder, I need to resolve ../node_modules/bootstrap-sass, and it get's more complicated with more nested folders. In addition, this does not work for globally installed modules.

var packageRoot = require.resolve('bootstrap-sass')
    .match(/^.*[\/\\]node_modules[\/\\][^\/\\]*/)[0];
console.log(packageRoot);

这适用于 node_modules 文件夹。正则表达式将匹配最后一个 node_modules 路径元素以及以下路径元素的所有内容。但是，如果将包的入口点设置为另一个包（例如main： c> c> c中的./node_modules/sub-package，则会失败.json ）。

This will work for local and global modules installed in node_modules folder. The regex will match everything up to the last node_modules path element plus the following path element. However this will fail if a package's entry point is set to another package (e.g. "main": "./node_modules/sub-package" in package.json).

var escapeStringRegexp = require('escape-string-regexp');

/**
 * Get the root path of a npm package installed in node_modules.
 * @param {string} packageName The name of the package.
 * @returns {string} Root path of the package without trailing slash.
 * @throws Will throw an error if the package root path cannot be resolved
 */
function packageRootPath(packageName) {
    var mainModulePath = require.resolve(packageName);
    var escapedPackageName = escapeStringRegexp(packageName);
    var regexpStr = '^.*[\\/\\\\]node_modules[\\/\\\\]' + escapedPackageName +
        '(?=[\\/\\\\])';
    var rootPath = mainModulePath.match(regexpStr);
    if (rootPath) {
        return rootPath[0];
    } else {
        var msg = 'Could not resolve package root path for package `' +
            packageName + '`.'
        throw new Error(msg);
    }
}

var packageRoot = packageRootPath('bootstrap-sass');
console.log(packageRoot);

此函数适用于 node_modules 文件夹。

我想知道这个相当简单的任务是否无法解决一种更简单，更少hacky的方式。对我而言，它看起来应该已经构建到Node.js中。有什么建议吗？

I wonder if this rather simple task cannot be solved in a simpler and less hacky way. To me it looks like something that should already be built into Node.js. Any suggestions?

推荐答案

试试这个：

require.resolve('bootstrap-sass/package.json')

返回：

path_to_my_project/node_modules/bootstrap-sass/package.json

您现在可以摆脱'package.json'路径后缀，例如：

You can now get rid of 'package.json' path suffix such as:

var path = require('path') // npm install path
var bootstrapPath = path.dirname(require.resolve('bootstrap-sass/package.json'))

因为每个包都必须包含 package.json 文件，这应该始终有效（参见）。

Since it is mandatory for every package to contain package.json file, this should always work (see What is a package?).

这篇关于Node.js：获取已安装的npm包的（绝对）根路径的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！