cant read multiple types in an array and cant have a property named "type"

[StevieSeccombe1]

schema-to-yup - v 1.9.14
yup - 0.27.0

I have a json schema with properties of type ["string, "null"] but it cant read this properly. How do I go about adding my own custom type handler for this?

I also have a property called "type" which it tries to use as the property's type. Is there a way of getting around this too?

thanks

[kristianmandrup]

Please update to the latest version which has better support for these scenarios.

• Custom type handlers
• Custom constraint handler functions

However, your concrete example (mixed multi type) is not currently supported out of the box.

You would need to either extend YupBuilder for propToYupSchemaEntry or pass in a custom factory function createYupSchemaEntry as part of the config object.

  createYupSchemaEntry({ schema, name, key, value, config }) {
    const yupEntry = config.createYupSchemaEntry({
      schema,
      name,
      key,
      value,
      config
    });
    return yupEntry; 
  }

In your case the value would then be["string, "null"] and you would have to take it from there...

The default function is

import { YupSchemaEntry } from "./entry";

function createYupSchemaEntry(opts = {}) {
  // const { schema, name, key, value, config } = opts;
  return new YupSchemaEntry(opts).toEntry();
}

So likely you would need to extend the class YupSchemaEntry defined in entry.js

The key method is toEntry

In particular I would extract out the part from line 61 into a function toSingleTypeEntry and then do:

  return this.toMultiTypeEntry() || this.toSingleTypeEntry() || this.toDefaultEntry()

and then implement toMultiTypeEntry as you see fit.

[kristianmandrup]

Would love to see a PR for that :)

[kristianmandrup]

I've just started a multi-type branch you can play with and have a look at to get a better feel for it.

See custom entry builders docs

[kristianmandrup]

Could you please a PR with a failing spec that illustrates the problem:

"I also have a property called "type" which it tries to use as the property's type"

Thanks

[kristianmandrup]

I've added (failing) tests for the scenarios described.

[kristianmandrup]

In this case above it would result in a shape of string().nullable().

Otherwise you would have to use mixed() with some custom validation logic as far as I understand yup.

See also using yup test for custom validation logic

[kristianmandrup]

const createValueSchema = (value, schema = yup) => {
  if (value === 'string') {
    return schema.string()
  }
  if (value === 'null') {
    return schema.nullable()
  }
  return schema
}

let constraintListValue = ['string', 'null']
let schema = yup.mixed().test({
  name,
  exclusive: true,
  params: {},
  message: '${path} must be less than ${max} characters',
  test: value => {
      const schema = constraintListValue.reduce((accSchema, constraintValue) => {
        return createValueSchema(constraintValue, accSchema)
    }, null)
    return schema.validateSync(value)
  }
});

[kristianmandrup]

Latest commit includes better support for this and some better implementation suggestions for how to achieve this