Firelaw

0.0.0 verified Fri May 01 auth: no javascript

Firelaw is a TypeScript transpiler that lets you write type-safe and scalable Firestore Security Rules using TypeScript syntax. Version 0.0.0 is an initial release with rapid iteration. It differentiates by enabling full TypeScript type checking and IDE support for rules, reducing runtime errors compared to writing raw Firebase rules. The library compiles TypeScript to Firestore rules format, handling complex rule generation with type safety.

Common errors

error ReferenceError: firelaw is not defined ↓

cause Using CommonJS require instead of ESM import.

fix

Use import { firelaw } from 'firelaw' and ensure your project is ESM (type: module in package.json or .mjs file).

error TypeError: firelaw is not a function ↓

cause Firelaw is a tagged template tag, not a function that returns a string directly.

fix

Use firelaw... (backtick template literal) instead of firelaw('...').

Warnings

deprecated firelaw() tagged template literal syntax may change in future versions. ↓

fix Watch for breaking changes in pre-1.0 releases.

gotcha The package is in initial development (v0.0.0). APIs are unstable and may break frequently. ↓

fix Pin to specific version and test thoroughly.

gotcha Cannot use JavaScript; only TypeScript is supported due to compile step. ↓

fix Write rules in TypeScript files with .ts extension.

gotcha Firelaw does not support all Firestore rule features; check documentation for limitations. ↓

fix Review the list of supported functions and operators.

Install

npm install firelaw

yarn add firelaw

pnpm add firelaw

Imports

firelaw

wrong

const firelaw = require('firelaw')

correct

import { firelaw } from 'firelaw'

ESM-only package; CJS require will fail.

Resource

wrong

import Resource from 'firelaw'

correct

import { Resource } from 'firelaw'

Resource is a named export, not default.

Request
```
import { Request } from 'firelaw'
```
TypeScript type for request context in rules.

Quickstart

Demonstrates basic Firelaw usage: writing a Firestore rule that allows read only if user is authenticated.

import { firelaw, Resource, Request } from 'firelaw'

const rules = firelaw`
  match /databases/{database}/documents {
    match /{document=**} {
      allow read: if ${(req: Request, res?: Resource) => req.auth != null};
    }
  }
`

console.log(rules)