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Zod - TypeScript-first schema declaration and validation library #9

Zod - TypeScript-first schema declaration and validation library #9

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Nhan Nguyen
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✨ Complex Schema Validation ✨

Our Form has name, email, and optionally will have phoneNumber and website.

const Form = z.object({
  name: z.string(),
  phoneNumber: z.string().optional(),
  email: z.string(),
  website: z.string().optional(),
});

export const validateFormInput = (values: unknown) => {
  const parsedData = Form.parse(values);

  return parsedData;
};

We want to put some constraints on what the values can be.

The user should not be able to pass an invalid URL, phone numbers, or website URLs.

We will find Zod APIs for adding validation to our Form types.

Phone numbers should have the right amount of characters.

Email addresses and URLs should look right.

👉 Solution:

The strings section of the Zod docs includes several examples of validation helpers that can be used to validate our Form types.

Here is what the Form schema looks like now:

const Form = z.object({
  name: z.string().min(1),
  phoneNumber: z.string().min(5).max(20).optional(),
  email: z.string().email(),
  website: z.string().url().optional(),
});

name has min(1) added because we can’t pass in an empty string.

phoneNumber are constrained with min(5) and max(20) while still being optional.

Zod also has built-in validators for email and url, saving us from writing our own.

Note that we can not use .optional().min() because min does not exist on the optional types. This means we have to put .optional() at the end after other validations.

There are additional validation resources linked in the Zod docs.

I hope you found it useful. Thanks for reading. 🙏

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