Is it possible to use zod to validate a comma-separated string

[grug]

Hey there,

I'm trying to validate some queryparams coming through to an endpoint, i.e. { foo: '1,2,3,4' }. I'd like to use zod to validate that the value of foo is a comma-separated string. Is anything like this possible?

[JacobWeisenburger]

what should the value of foo be?

• string array?
• number array?
• something else?

[grug]

Yep the second I read this I feel stupid 😂 probably doesn't make sense to try have this sort of validation as it's way too hairy.

[JacobWeisenburger]

there might be a way to do what you are asking. I'm just wanting to fully understand what you want before I start making suggestions.

[grug]

I think in my example, I'd be looking at foo as having a value being a comma-separated string, where each comma-separated item passes validation for a number. I'm aware I could do this without zod, but I was just seeing if there's a mechanism available to do something like this.

[JacobWeisenburger]

Is this what you are looking for?

const schema = z.object( {
    foo: z.string()
        .transform( value => value.split( ',' ).map( Number ) )
        .pipe( z.number().array() ),
} )

console.log( schema.parse( { foo: '1,2,3,4' } ) )
// { foo: [ 1, 2, 3, 4 ] }

[grug]

That is exactly what I'm looking for.

Thanks @JacobWeisenburger - you are a legend.

[staciax]

thanks <3 it's work

const schema = z.object({
	foo: z
		.string()
		.transform((value) => value.split(','))
		.pipe(z.string().trim().url().array()),
});

console.log(
	schema.parse({ foo: 'http://localhost,    http://localhost:8000' }),
);

{
  foo: [ "http://localhost", "http://localhost:8000" ],
}