parse and get valid values

[rezaUniqe]

I am wondering how we can use Zod to parse an object and retrieve only the valid values while ignoring the invalid ones. For example, imagine having a JSON object:

const test = { name: "name", age: "invalid" };

Given the following Zod schema:

const schema = z.object({
  name: z.string(),
  age: z.number()
});

When I use schema.validParse(test), I want to get an object with only the valid fields, like this:

{name: "name"}

How can I achieve this?

[ghosty2004]

Hi!
I just made a function which help you to achive what you want.

/**
 * This function will remove the fields that are not valid according to the schema
 * @template T
 * @param {z.ZodType<T>} schema - The Zod schema to validate against.
 * @param {z.ZodObject} object - The object to parse against the schema.
 * @returns {Partial<T>} - The parsed and validated object with all fields optional.
 */
const parseSchemaObject = (schema, object) => {
    try {
        return schema.parse(object);
    } catch (e) {
        if (!(e instanceof z.ZodError))
            throw new Error("Failed to parse object");

        const errorFields = e.errors.map((err) => err.path[0]);
        const fieldsToOmit = errorFields.reduce((obj, key) => {
            obj[key] = object[key];
            return obj;
        }, {});

        try {
            return schema.omit(fieldsToOmit).parse(object);
        } catch {
            throw new Error("Failed to parse object");
        }
    }
};

Example of usage:

import z from "zod";

const test = { name: "name", age: "invalid" };

const schema = z.object({
    name: z.string(),
    age: z.number(),
});

const parsed = parseSchemaObject(schema, test);
console.log(parsed);

[marilari88]

hi @rezaUniqe, what about this?

z.object({
  name: z.string(),
  age: z.number().catch(undefined)
})

[its-jz]

This changes the expected output shape of the schema though?