implement some means of retrieving secret values

[nlf]

there is some desire to allow getconfig to retrieve values from somewhere other than a file on disk or environment variables, however this requires a bit of planning to come up with a reasonable solution since many things in node are by their very nature asynchronous and getconfig is intended to work synchronously.

some possible solutions:

1. make getconfig asynchronous, this would be a new semver-major but would allow us to perform async actions without any additional work. instead of const config = require('getconfig') we could return a promise and have const config = await require('getconfig')

pros:

• minimal usage change

cons:

• node doesn't yet have top level await for commonjs (it does for esm modules) so there's some inconvenience factor
• it would definitely be a breaking change

2. use a built in worker thread and Atomics to run async actions and wait for their results

pros:

• can perform async actions (the desired effect) while appearing to still be synchronous

cons:

• requires built in implementation or working out a plugin system of some kind to allow multiple sources (or see 4 below)
• configuring external sources would require some additional syntax

3. allow a value to be populated by an arbitrary external command

pros:

• would allow users to get a value in a very flexible way while maintaining synchronous loading thanks to spawnSync/execSync

cons:

• configuring a value to be read through an external command would require a reasonable way of expressing the desired command
• the entire command would have to be provided for every value coming from the given source

4. (middle ground between 2 and 3) allow users to provide a javascript module within their project that retrieves a value however they choose, run their module in a worker thread and use atomics to wait for its result

pros:

• very flexible
• maintains overall synchronous nature
• non-breaking

cons:

• users would likely have to provide their own modules for data retrieval
• those modules will have to perform their own configuration somehow (who configures the config fetcher?)

[owenniblock]

I think I would lean towards the simplest option (which in my mind is the first). However I'm not sure I fully comprehend this disadvantage:

node doesn't yet have top level await for commonjs (it does for esm modules) so there's some inconvenience factor

Naive question alert: could you change the library to be async but provide a sync method of calling it?

So usage could become something like:

// Get the config async:
const config = await require('getconfig').asyncConfig

// Get the config sync:
const config = require('getconfig').config

Maybe it could default to sync?

I assume that the complexities of the libraries inner workings means that this is not a feasible option but figured there's no harm asking 🙂