Zod: allow undefined as default value for a required field

[knoefel]

I have a simple form to "add/edit" an entity. My (simplified) zod schema looks like this:

const schema = z.object({
  host: z.string(),
  port: z.number()
});

The default values for the "add" use case look like this:

const defaultValues = {
  host: "Host"
};

These are my requirements for the port field:

• the field is required
• the field value is a number
• upon the "add" use case, it should be possible to provide an empty field to the user (so it would fail if the user hits submit before entering a value)
• it should be possible to set default values for other fields in the schema, without setting a value for the port field

So for the "add" use case most of the form fields should be empty (except the host field), only when i edit i want to set the current values for that entity as the default values.

The problem is, that zod won't allow this, as i must set a default value for the port field as it is a required field. From an UX perspective this isn't optimal, as i want to leave the port field empty and force the user to enter a value.

The only way i've found so far is to set the port field to 0. But for the reason above this is not a good solution.

I wonder if there are other solutions to this problem? It seems like this shouldn't be rare case, as it is usually a requirement to pre-fill some fields, while other's must explicitly filled out by the user.

[ecyrbe]

Just distinct form completion from form validation.