How to mutate node-config in memory

Question

I'm trying to mutate the value of my config in memory for testing, I've tried adding process.env.ALLOW_CONFIG_MUTATIONS=true in several spots in the application, as well as through the command line and my .env file.

The config.util.getEnv('ALLOW_CONFIG_MUTATION') method always returns undefined.

I've also tried using importFresh and MockRequest as per examples I've seen online, neither of which allow me to mutate the config in memory, and then reset the value later.

Does anyone have any idea about this?

Update : here's an example of what I'm trying to accomplish

const config = require (config);
const app = new App(config)

it(`does a thing with base config`, () => {  ...  }

it('does a thing with modified config, () => {  
    // here i would need to modify my config value and
    // have it change the original config that's currently in 
    // application memory

    config = newConfig  

    expect(config.get('newValues')).to.equal(true)
}

Thanks!

Answer 1

If it is the same config module that I have used (I think I is) then add a custom-environment-variables.js OR test.js with you test config.

test.js will need an ENV=test to work and the custom-environment-variables need something like (for Mac's and NPM) $ npm run funcTest -> yarn serverRunning && NODE_ENV=test wdio wdio.conf.js .

the JSON will look something like

{
  test: 'Value'
}