lnurl-auth

Instructions for implementing lnurl-auth in rails.

Here's an example of how you might implement LNURL-auth in a Rails server:

First, you'll need to add a route to handle the callback request from the user's wallet.

Copy code #config/routes.rb post '/lnurl-auth/callback', to: 'lnurl_auth#callback' Then, you'll need to create a controller to handle the callback request and authenticate the user.

Copy code #app/controllers/lnurl_auth_controller.rb class LnurlAuthController < ApplicationController def callback k1 = params[:k1] tag = params[:tag] pr = params[:pr]

# Retrieve the user associated with the given k1
user = User.find_by(lnurl_auth_k1: k1)

if user.nil?
  # Handle the error if the user is not found
  render json: {status: 'FAIL', statusMessage: 'User not found'}, status: :unauthorized
else
  # Verify the authenticity of the request
  if tag == "auth"
      if user.authenticate_lnurl_auth(pr)
        # User is authenticated, log them in and return success
        sign_in(user)
        render json: {status: 'OK', statusMessage: 'User authenticated'}, status: :ok
      else
        # Handle the error if the authentication fails
        render json: {status: 'FAIL', statusMessage: 'Authentication failed'}, status: :unauthorized
      end
  elsif tag == "login"
      if user.login_lnurl_auth(pr)
        # User is authenticated, log them in and return success
        sign_in(user)
        render json: {status: 'OK', statusMessage: 'User logged in'}, status: :ok
      else
        # Handle the error if the login fails
        render json: {status: 'FAIL', statusMessage: 'Login failed'}, status: :unauthorized
      end
  else
    # Handle the error if the tag is not recognized
    render json: {status: 'FAIL', statusMessage: 'Invalid tag'}, status: :unauthorized
  end
end

end end In this example, the authenticate_lnurl_auth and login_lnurl_auth methods should be implemented in your user model. These methods should verify the authenticity of the request and log the user in if the request is valid.

Finally, you will need to create an endpoint on your server that will generate the LNURL and return it to the client.

Copy code #app/controllers/users_controller.rb class UsersController < ApplicationController def login user = User.new user.lnurl_auth_k1 = SecureRandom.hex user.save lnurl = "lnurl1auth+https://yourserver.com/lnurl-auth/callback?k1=#{user.lnurl_auth_k1}&tag=login" render json: {lnurl: lnurl} end end Keep in mind that this is just an example and you will need to adapt it to fit your specific use case. You will also need to take care of the security and validate