Checking if the app is using the proper version of node.js

Question

Checking if the app is using the proper version of node.js

I have a basic Express app with a package.json that looks like this

{
    "name": "blog",
    "version": "0.0.1",
    "dependencies": {
        "express": "~3.0.0"
    },
    "engines": {
        "node": "0.9"
    }
}

Obviously node itself doesn't care about contents of this file. Is there a way to start an app so that npm would read it and report an error?

node.js
npm

Answer 1

since the package.json is only a json file you can easily load and parse it, then compare the engines.node value with process.version and report an error.

no need to do something with npm here.