将命令行参数发送到 npm 脚本 [英] Sending command line arguments to npm script

问题描述

我的 package.json 的 scripts 部分目前看起来像这样:

"scripts": {开始":节点 ./script.js 服务器"}

...这意味着我可以运行 npm start 来启动服务器.到目前为止一切顺利.

但是，我希望能够运行类似 npm start 8080 的东西，并将参数传递给 script.js(例如 npm开始 8080 => node ./script.js 服务器 8080).这可能吗?

解决方案

npm 2 及更新版本

可以将参数传递给npm run，因为npm 2 (2014).语法如下:

npm run <命令>[-- ]

注意 -- 分隔符，用于分隔传递给 npm 命令本身的参数和传递给脚本的参数.

以package.json为例:

 脚本":{咕噜":咕噜"，服务器":节点 server.js"}

以下是将参数传递给这些脚本的方法:

npm run grunt -- task:target//调用`grunt task:target`npm run server -- --port=1337//调用`node server.js --port=1337`

注意:如果您的参数不是以 - 或 -- 开头，则具有明确的 -- 不需要分隔符；但为了清楚起见，最好还是这样做.

npm run grunt task:target//调用`grunt task:target`

注意下面的行为差异(test.js 有 console.log(process.argv)):以 - 或 -- 被传递给 npm 而不是脚本，并在那里被默默吞噬.

$ npm run test foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', 'foobar']$ npm run test -foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js']$ npm run test --foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js']$ npm run test -- foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', 'foobar']$ npm run test -- -foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', '-foobar']$ npm run test -- --foobar['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', '--foobar']

当你使用一个参数npm实际使用时，区别会更明显:

$ npm test --help//这是伪装的`npm --help test`npm 测试 [-- <args>]别名:tst, t

要获取参数值，请查看此问题.要读取命名参数，最好使用解析库，例如 yargs 或 minimist;nodejs 全局公开 process.argv，包含命令行参数值，但这是一个低级 API(以空格分隔的字符串数组，由操作系统提供给节点可执行文件).>

---

Edit 2013.10.03:目前无法直接使用.但是在 npm 上打开了一个相关的 GitHub 问题来实现你要求的行为.似乎共识是实现这一点，但这取决于之前解决的另一个问题.

---

原始答案 (2013.01): 作为某种解决方法(虽然不是很方便)，您可以执行以下操作:

从 package.json 说你的包名是 myPackage 你也有

脚本":{开始":节点 ./script.js 服务器"；}

然后在package.json中加入:

配置":{我的端口":8080"}

在你的 script.js 中:

//如果脚本不是通过npm run-script"调用的，则默认为 8080；但直接var port = process.env.npm_package_config_myPort ||8080

这样，默认情况下 npm start 将使用 8080.但是您可以配置它(该值将由 npm 存储在其内部存储中):

npm config set myPackage:myPort 9090

然后，当调用 npm start 时，将使用 9090(package.json 中的默认值被覆盖).

The scripts portion of my package.json currently looks like this:

"scripts": {
    "start": "node ./script.js server"
}

...which means I can run npm start to start the server. So far so good.

However, I would like to be able to run something like npm start 8080 and have the argument(s) passed to script.js (e.g. npm start 8080 => node ./script.js server 8080). Is this possible?

解决方案

npm 2 and newer

It's possible to pass args to npm run since npm 2 (2014). The syntax is as follows:

npm run <command> [-- <args>]

Note the -- separator, used to separate the params passed to npm command itself, and the params passed to your script.

With the example package.json:

  "scripts": {
    "grunt": "grunt",
    "server": "node server.js"
  }

here's how to pass the params to those scripts:

npm run grunt -- task:target  // invokes `grunt task:target`
npm run server -- --port=1337 // invokes `node server.js --port=1337`

Note: If your param does not start with - or --, then having an explicit -- separator is not needed; but it's better to do it anyway for clarity.

npm run grunt task:target     // invokes `grunt task:target`

Note below the difference in behavior (test.js has console.log(process.argv)): the params which start with - or -- are passed to npm and not to the script, and are silently swallowed there.

$ npm run test foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js',  'foobar']

$ npm run test -foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js']

$ npm run test --foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js']

$ npm run test -- foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', 'foobar']

$ npm run test -- -foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', '-foobar']

$ npm run test -- --foobar
['C:\Program Files\nodejs\node.exe', 'C:\git\myrepo\test.js', '--foobar']

The difference is clearer when you use a param actually used by npm:

$ npm test --help      // this is disguised `npm --help test`
npm test [-- <args>]

aliases: tst, t

To get the parameter value, see this question. For reading named parameters, it's probably best to use a parsing library like yargs or minimist; nodejs exposes process.argv globally, containing command line parameter values, but this is a low-level API (whitespace-separated array of strings, as provided by the operating system to the node executable).

---

Edit 2013.10.03: It's not currently possible directly. But there's a related GitHub issue opened on npm to implement the behavior you're asking for. Seems the consensus is to have this implemented, but it depends on another issue being solved before.

---

Original answer (2013.01): As a some kind of workaround (though not very handy), you can do as follows:

Say your package name from package.json is myPackage and you have also

"scripts": {
    "start": "node ./script.js server"
}

Then add in package.json:

"config": {
    "myPort": "8080"
}

And in your script.js:

// defaulting to 8080 in case if script invoked not via "npm run-script" but directly
var port = process.env.npm_package_config_myPort || 8080

That way, by default npm start will use 8080. You can however configure it (the value will be stored by npm in its internal storage):

npm config set myPackage:myPort 9090

Then, when invoking npm start, 9090 will be used (the default from package.json gets overridden).

这篇关于将命令行参数发送到 npm 脚本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IT屋！