JWT Strategy

A Remix Auth strategy for working with JWT.

This strategy is influenced by Ktor's JSON Web Tokens-related library and the express-jwt library.

In other words, when Remix is used as an API-only application, this strategy comes into effect.

Supported runtimes

| Runtime | Has Support | | ---------- | ----------- | | Node.js | ✅ | | Cloudflare | ✅ |

This strategy has been tested to work with Node.js as well as with Cloudflare workers.

Run the following command to obtain a token to verify that this strategy works with Cloudflare workers.

curl -X POST \
  -H "Content-Type: application/json" \
  -d '{"username": "[email protected]" }' \
  https://remix-auth-jwt.takagimeow.workers.dev/create-token

{
  "success": true,
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6ImV4YW1wbGVAZXhhbXBsZS5jb20iLCJpYXQiOjE2NzY4NjgxMTl9.lQj4xzTxx26jL6AKH-1qpEgKuLCgZqXOrsHcRPGK6tM"
}

Then run the following command to verify that you can authenticate with this token.

curl -X GET \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6ImV4YW1wbGVAZXhhbXBsZS5jb20iLCJpYXQiOjE2NzY4NjgxMTl9.lQj4xzTxx26jL6AKH-1qpEgKuLCgZqXOrsHcRPGK6tM" \
  https://remix-auth-jwt.takagimeow.workers.dev/authenticate-required

{ "success": true, "username": "[email protected]", "iat": 1676868119 }

Check out this repository to learn how to implement this strategy for the applications you want to run on Cloudflare Workers.

API

The parameter passed as the first argument when this strategy class is initialized contains the following:

| Name | Type | Description | | ---------- | ---------------------------------------------------------------------- | --------------------------------------------------- | | secret | string | The secret used to sign the token. | | algorithms | Algorithm[] | The algorithms used to sign the token. | | getToken? | (req: Request) => string | undefined | Promise<string | undefined>; | A function that returns the token from the request. |

How to use

First, install the strategy, [email protected], [email protected] and Remix Auth.

$ npm install remix-auth remix-auth-jwt [email protected] [email protected]

Then, create an Authenticator instance.

// app/auth.server.ts
import { Authenticator } from "remix-auth";
import { sessionStorage } from "~/session.server";

export let authenticator = new Authenticator<{ requestname: string }>(
  sessionStorage
);

And you can tell the authenticator to use the JwtStrategy.

import { JwtStrategy } from "remix-auth-jwt";

// The rest of the code above here...

authenticator.use(
  new JwtStrategy(
    {
      secret: "s3cr3t",
      algorithms: ["HS256"] as Algorithm[],
    },
    // Define what to do when the request is authenticated
    async ({ payload, context }) => {
      // You can access decoded token values here using payload
      // and also use `context` to access more things from the server
      return payload;
    }
  ),
  // each strategy has a name and can be changed to use another one
  "jwt"
);

In order to authenticate a request, you can use the following inside of an loader function:

import { LoaderArgs } from "@remix-run/server-runtime";
import { authenticator } from "~/auth.server";

export async function loader({ params, request }: LoaderArgs) {
  const result = await authenticator.authenticate("jwt", request);
  return result;
  try {
    const result = await authenticator.authenticate("jwt", request);
    /* handle success */
  } catch (error: unknown) {
    /* handle error */
  }
}

In order to authenticate a request, you can use the following inside of an action function:

import type { ActionArgs } from "@remix-run/server-runtime";
import { authenticator } from "~/auth.server";

export const action = async ({ request }: ActionArgs) => {
  try {
    const result = await authenticator.authenticate("jwt", request);
    switch (request.method) {
      case "POST": {
        /* handle "POST" */
      }
      case "PUT": {
        /* handle "PUT" */
      }
      case "PATCH": {
        /* handle "PATCH" */
      }
      case "DELETE": {
        /* handle "DELETE" */
      }
    }
  } catch (error: unknown) {
    /* handle error */
  }
};