Zod schema generation --> I want nullish() instead of optional()

[RapidLars]

Hej everyone,

we are generating our api types and dtos with orval, and now we are exploring to use zod for frontend validation. I discovered that orval also may generate zod schemas, which is very neat!

Lets have a look at (partially) generated zod schema:

zod.object({
  "street": zod.string().optional().describe('Street name'),
  "houseNumber": zod.string().optional().describe('House number'),
  "zipCode": zod.string().optional().describe('Postal code'),
  "city": zod.string().optional().describe('City of residence')
})

All properties, that are not required, are marked optional. The backend api, which is written in Java, does not distinguish between undefined (--> optional) and null (--> nullable) values, they are interchangable. But the frontend validation using this schema would now complain about null values. So I would like to have nullish() (which combines optinal and nullable) instead everywhere optional is used.

The schema I would love to see generated would look like this:

zod.object({
  "street": zod.string().nullish().describe('Street name'),
  "houseNumber": zod.nullish().optional().describe('House number'),
  "zipCode": zod.string().nullish().describe('Postal code'),
  "city": zod.string().nullish().describe('City of residence')
})

Is there a way to accomplish that? Using a configuration option, a postprocessor or something?
Thanks for advice towards the right direction! :)

Lars

[melloware]

@sentik is the zod expert any thoughts here?

[Lys-is]

I had the same problem. I use this postprocess

const zodFilePath = 'pathToZodGeneratedFile';
processZodFile(zodFilePath);
function processZodFile(filePath: string): void {
  if (!existsSync(filePath)) {
    return;
  }
  let content = readFileSync(filePath, 'utf-8');
  content = content.replace(/\.optional\(\)/g, '.nullish()');
  writeFileSync(filePath, content);
}