Custom properties

[blujedis]

Looking for a suggestion, creating a minimalist lib for Mongodb's native driver, looking for better types as to the why.

There are some cases where we'd like to pass along some custom properties that aren't really part of the validation Schema but required for example to map a relationship.

Looking for any suggestions anyone might have.

[samhuk]

If I understand you correctly, you want to attach some custom metadata to a property? If so, I've had success with a setup something like this:

import t from 'typebox'

type PropMetadata = {
  /** Declares whether this property is unique across all other records. */
  unique?: boolean
}

/** A helper for creating `PropMetadata` in a type-safe way. */
const propMetadata = (metadata: PropMetadata): { 'x-metadata': PropMetadata } => {
  return { 'x-metadata': metadata }
}

const hasPropMetadata = (
  obj: Record<string, any>,
): obj is { [key: PropertyKey]: unknown; 'x-metadata': PropMetadata } => obj['x-metadata'] != null

// Example of writing custom properties to schema
export const MY_SCHEMA = t.Object({
  name: t.String({ ...propMetadata({ unique: true }) })
})

// Example of reading custom properties off of a schema
const getPropMetadata = (obj: Record<string, any>): PropMetadata | undefined =>
  hasPropMetadata(obj) ? obj['x-metadata'] : undefined

[blujedis]

Gone another route for the moment but thank you @samhuk this is essentially what we were looking for. Like prove helpful down the road...