节点包 - 是否可以在package.json中插入变量？

Question

I have a static site that compile Sass using node-sass .

Currently I'm using Grunt to watch the file, but I feel it's overkill because I can use their built-in CLI.

So I add this in my package.json:

// package.json
...
"scripts": {
  "sass": "node-sass -w input/dir -o output-dir/" 
}

The problem is, I need to require a Sass framework module (installed globally) in the --include-path . I can do this in Gruntfile:

// Gruntfile.js
sass: {
  options: {
    includePaths: require("the-framework").includePaths()
  },
  ...
},

So the first thing that come to my mind is to interpolate the string like:

// package.json
...
"scripts": {
  "sass": "node-sass -w input/dir -o output-dir/ --include-path " + require("the-framework").includePaths()
}

And as expected, it doesn't work. Well the script runs, but the interpolated variable is ignored.

Any solution or alternative? If possible, I would prefer not to create additional file just to store the variable.

Thanks

Answer 1

I dont know is it a right way to do it, but I can explain how I will would solve this task.

You cant interpolate variables in package.json , cause it must be valid json. That you can is to write bash commands here.

1) You can write node command that will needed result. You should take care if includePaths() does not return string.

Node options:
  -e, --eval script     evaluate script
  -p, --print           evaluate script and print result

So it would be something like

node -e "console.log(require('the-framework').includePaths())"

Or shorter version with --print

node -p "require('the-framework').includePaths()"

2) Inline output of previous command into sass script. Take care of right escaping.

{
  "scripts": {
      "sass": "node-sass -w input/dir -o output-dir/ --include-path $(node -p \"require('the-framework').includePaths()\")"
  }
}

More info about executing bash command you can find here .

PS Windows version differs

{
  "scripts": {
      "sass": "FOR /f \"delims=\" %v IN ('node -p \"require('edje').includePaths()[0]\"') DO node-sass -w assets/sass -o assets/css --include-path \"%v\""
  }
}

More info you can find here .

Answer 2

You can something like this:

“scripts”: {
  “sass”: “node-sass --include-path scss scss/main.scss   public/css/main.css”
},

Answer 3

There are many ways you could solve this with npm scripts.

The first one that comes to my mind by looking at your specific need is, npm accepts extra parameters when calling a script. For example:

npm run sass -- path/to/the-framework

This will resolve to:

node-sass -w input/dir -o output-dir/ --include-path path/to/the-framework

---

Another way would be to move your code in a .js executable file (Node), let's call it watch-sass.js .

So your script will look like:

"sass": "node watch-sass.js"

And you would run:

npm run sass

This way you have much more freedom to do anything you want in your file.

---

Possibilities are infinite really, you could leverage the power of bash script instead of JS if you want, they can all read/write environment variables. But you don't necessarily need them. For instance you could just have a shell script that writes a package.json for you (or Python, or Ruby...), with all the variables already in place. But in the end I think it's just a matter of taste, use what you find simpler or more comfortable to use.