Fastify Hashids Plugin

A Fastify plugin for integrating Hashids into your routes, providing an easy way to encode and decode data, particularly useful for obscuring database IDs.

Installation

pnpm install fastify-hashids

Usage

import fastify from 'fastify';
import fastifyHashids from 'fastify-hashids';

const app = fastify();

await app.register(fastifyHashids, {
  hashidsOptions: {
    salt: 'your-secret-salt',
    minLength: 8,
    // Additional Hashids options if needed
  },
});

app.get('/', (request, reply) => {
  const id = 123;
  return {
    encodedId: id,
    idWithoutEncoding: id,
  };
});

await fastify.listen({ port: 3000 });

curl http://localhost:3000

the response will look like this:

{
  "encodedId":"Mj3",
  "idWithoutEncoding":123
}

Options

The plugin accepts the following options:

• hashidsOptions: An object with options to configure the Hashids instance. These options are passed directly to the Hashids constructor. Available options include salt, minLength, alphabet, and seps. You can find more options in the hashids.js repo.

• hashidsOptions.idRegexp: A regular expression that fastify-hashids uses to automatically identify properties as IDs. By default, it matches variations of "id, ids, ID, userID," etc. You can customize this regex to match your specific property names. Pass null to disable the regex-based property identification.

• hashidsOptions.propertyList: An array of property names to include in the hashing process. Properties listed here will be considered for encoding with Hashids, in addition to those identified by the idRegexp.

Route-Level Configuration

You can disable the Hashids functionality for specific routes by adding the disableHashids property to the route's configuration object:

app.get(
  '/api/sensitive-data',
  {
    config: {
      disableHashids: true,
    },
  },
  async (req, reply) => {
    // ... handle route without Hashids encoding
  },
);

License

This project is licensed under the MIT License.

Contributing

Contributions are welcome! If you find a bug, have suggestions for improvement, or want to add new features, please open an issue or create a pull request.