codechaotic / eznv Goto Github PK

Excluding the options object from a call to Schema.load() or Schema.loadSync() results in a typescript error.

Expected 1 arguments, but got 0.

These methods should be callable without supplying an options object since all options have safe defaults.

Current documentation is minimal and could be improved

Add an ability to add custom validation to any configuration
Add an ability to transform the resulting configuration value

Method 1: Dedicated validation and transform function as an option for interpreters. There doesn't seem to be an obvious return value for the validator. Would it be better to provide special handling for errors thrown from within this method instead?

EZ.Number({
  validate (x: string): boolean {
    // return false or maybe just throw error?
  }
  transform (x: number): any {
    // The return type of the transform method would need to be
    // used on the resulting env object
  }
})

Method 2: Singular function option to do any post-processing. Functions as both a validator and a transformer. Would it make sense to have a pre-processing function as an option as well? before and after, pre and post, or similar?

EZ.Integer({
  after (x: number): any {
    if (x % 2 === 1) throw new Error('Must be an even number')
    else return x / 2
  }
})

This may be solvable alongside #11

In addition to String, Number, Integer, and Boolean, users may have their own unique parsing rules to apply to their environment variables. This could include validation of the raw value, as well as custom result types.

Off the wall idea for the design:

import EZ from 'eznv'

interface SomeType {
  //
}

const schema = EZ.Schema({
  variable: EZ.Custom<SomeType>({
    parse (x: string) : SomeType {
      // custom parsing logic
      return { /* some type */ }
    }
  })
})