Typesafe CSV

An opinionated typesafe CSV serialization library for arbitarary objects leverging Papaparse and Zod

Getting Started

CsvSerializer takes a column schema in the form of [CSV Header, Object Keypath, ZodType]

Zod 4.1's codec feature can be used to control serialization of non-string types where:

• decode: CSV -> Object
• encode: Object -> CSV

import { z } from 'zod';
import { CsvSerializer } from '@akiroz/typesafe-csv';

const serializer = new CsvSerializer([
    ['ID', 'id', z.string().min(1)],
    ['Status', 'status', z.enum(['active', 'inactive']).optional()],
    ['Is Admin', 'isAdmin', z.stringbool().optional()],
    [
        'Created At',
        'meta.createdAt',
        z
            .codec(z.string(), z.date(), {
                decode: (s) => new Date(s),
                encode: (d) => d.toISOString().split('T')[0],
            })
            .optional(),
    ],
    [
        'Score',
        'meta.scores.primary',
        z
            .codec(z.string().regex(/^\d+$/), z.number().int(), {
                decode: (s) => Number(s),
                encode: (n) => String(n),
            })
            .optional(),
    ],
] as const);

const data = [
    {
        id: '201',
        status: 'inactive' as const,
        isAdmin: false,
        meta: {
            createdAt: new Date('2023-12-25'),
            scores: { primary: 100 },
        },
    },
    {
        id: '202',
        // status is undefined
        isAdmin: true,
        meta: {
            createdAt: new Date('2024-01-01'),
            scores: { primary: 50 },
        },
    },
];

const csvStr = serializer.export(data);

const data2 = serializer.import(csvStr);

ID	Status	Is Admin	Created At	Score
201	inactive	false	2023-12-25	100
202		true	2024-01-01	50

Empty values in CSV are converted to undefined and nullish JS values are serialized to an empty cell.

.import() automatically infers type information from the schema:

CSV Serialization Config

This library is simply a wrapper around Papaparse, the constructor takes a 2nd argument where Papaparse config can be specified:

const tsvSerializer = new CsvSerializer([/* ... */], {
    parse: {
        delimiter: '\t'
    },
    unparse: {
        delimiter: '\t'
    }
});