npm_package_version is undefined

[cawoodm]

• Version: v13.2.0
• Platform: Windows Server 2012 R2

process.env.npm_package_version is "sometimes" undefined i.e. on some of our systems/apps it appears and on others it's undefined although we have a valid value set in package.json.

What is the rule/reason for npm_package_version being set or not?

[richardlau]

At a guess it'll be whether the app was started via an npm script (in which it should be set) or run directly as node <app> as Node.js doesn't know anything about npm environment variables.

[cawoodm]

You nailed it!

What a pity as we want our running apps to know their version. I guess we'll have to require('./package.json') or something.

[davidzwa]

@cawoodm you can still provide interoperability by setting the environment variable yourself. Yes this does include path.join(__dirname, 'package.json') kind of approach, but to be honest this is what you do by running NPM scripts anyway.

So much for reviving an old thread ^^

[Benjythebee]

What a pity as we want our running apps to know their version. I guess we'll have to require('./package.json') or something.

An issue I have with require('./package.json') is the security concern:

Doing this with Browserify has security implications.
Be careful not to expose your package.json to the client, as it means that all your dependency version numbers, build and test commands and more are sent to the client.
If you're building server and client in the same project, you expose your server-side version numbers too. Such specific data can be used by an attacker to better fit the attack on your server.

good old stackoverflow

I guess I'll use genversion

[kalnode]

Re: package.json method

If it helps, you would presumably just pass the version ...

const fs = require('fs')
const packageJson = fs.readFileSync('./package.json')
const version = JSON.parse(packageJson).version || 0

Use discretion, you know, just like... other important data (like env's), some things you pass to the client, some not.

[Lsnsh]

https://docs.npmjs.com/cli/v10/using-npm/scripts#packagejson-vars

package.json vars
The package.json fields are tacked onto the npm_package_ prefix. So, for instance, if you had {"name":"foo", "version":"1.2.5"} in your package.json file, then your package scripts would have the npm_package_name environment variable set to "foo", and the npm_package_version set to "1.2.5". You can access these variables in your code with process.env.npm_package_name and process.env.npm_package_version, and so on for other fields.

See package.json for more on package configs.