Missing attributes during conversion using an ActionFunction with morphism()

If I have a definition such as:

interface Grade = {
  level: 'A'|'B'|'C'
  note?: string
}
interface Student = {
  name: string
  grade?: Grade
}

interface StudentDocument = {
  name: string,
  grade_data?: {
    level: 'A'|'B'|'C'
    note?: string
  }
}

const gradeSchema: StrictSchema<Grade> = {
  level: 'level',
  note: 'note'
}
const studentSchema: StrictSchema<Student, StudentDocument> = {
  name: 'name',
  grade: ({ grade_data }: any) => morphism(gradeSchema, grade_data),
}

Then the following function call will give:

morphism(studentSchema, { name: 'John Doe' })
{ name: 'John Doe',
  grade: [Function] }

I can wrap this in something like:

grade: ({ grade_data }: any) => grade_data ? morphism(gradeSchema, grade_data) : null

However it would be nice if the morphism never resulted in a function even with missing values. What is the strategy when working with optional values?

[emyann]

@terlar Thank you for your feedback !I did release a new version 1.10 with which it is possible to either strip the key when the value is undefined or provide a default value to replace undefined ones.

To do so it is now possible to create a schema with options using the createSchema function.

Strip undefined value

import { createSchema, morphism } from 'morphism'

const schema = createSchema<Target>({ keyA: 'somepath' }, { undefinedValues: { strip: true } })
// => {}

Default value fallback

import { createSchema, morphism } from 'morphism'

const schema = createSchema(
  { keyA: 'somepath' },
  {
    undefinedValues: {
      strip: true,
      default: () => null
    }
  }
);
// => { keyA: null }

Here’s a playground if you want to see it working: https://repl.it/@yrnd1/Morphism-undefined-values

Please let me know what you think about it and don’t hesitate if you have questions 😃

[terlar]

Sorry for the delay, I didn’t have time to update my implementation to use this until now. Just want to return here to say thank you and I am very satisfied with the current behavior. Keep up the good work 👍