RSQL to Prisma

A TypeScript library that seamlessly converts RSQL (RESTful Service Query Language) strings into where queries compatible with Prisma.

RSQL enables users to build queries that are both human-readable and machine-friendly, making it ideal for filtering data in applications. With rsql-prisma, you can effortlessly transform RSQL expressions or strings into Prisma where queries, facilitating advanced data retrieval with minimal boilerplate code. For more details about the RSQL specification, please refer to the FIQL read RFC about.

Table of Contents

• Installation
• Usage
• Type Coercion
• Contributing
• License

Installation

You can install the library via npm:

npm install -S rsql-prisma

Usage

Get from expression @rsql/builder:

import builder from '@rsql/builder';
import { rsqlExpressionToQuery } from 'rsql-prisma';

// equals
rsqlExpressionToQuery(builder.eq('name', 'John'));

Get from string:

import { rsqlStringToQuery } from 'rsql-prisma';

// equals
rsqlStringToQuery('name==John');

// greater than
rsqlStringToQuery('createdAt>1970-01-01');

// in
rsqlStringToQuery('name=in=(John,Doe)');

// like
rsqlStringToQuery('name==*John*');

// complex query
rsqlStringToQuery('title==foo*;(updated>=2024-01-01,title==*bar)');

Type Coercion

Default behavior (no Prisma DMMF provided)

By default, values are best-effort coerced using a guessing strategy:

• true / false → boolean

• numeric values → number (when safe)

• ISO date strings → Date

• JSON-like values → parsed JSON

• otherwise → string

This ensures backward compatibility and ease of use.

Deterministic coercion with Prisma DMMF (recommended)

If you provide a Prisma model name, rsql-prisma will use Prisma DMMF to coerce values deterministically based on the actual Prisma field type.

rsqlStringToQuery('age>=18', { prisma: { model: Prisma.ModelName.Student, dmmf: Prisma.dmmf } });

Supported Prisma types:

• Int

• Float

• Decimal (coerced to number)

• BigInt

• Boolean

• DateTime

• Enum

• Json

• String

For IN / NOT IN operators, values are automatically split and coerced element by element.

If a field cannot be resolved from the DMMF, the library falls back to the default guessing strategy.

Contributing

Contributions are welcome! Please submit a pull request or open an issue to discuss your changes.

License

This project is licensed under the MIT License. See the LICENSE file for details.