Add login via nostr (web extension)

app/controllers/users/sessions_controller.rb

@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+class Users::SessionsController < Devise::SessionsController
+  # before_action :configure_sign_in_params, only: [:create]
+
+  # GET /resource/sign_in
+  def new
+    session[:shared_secret] = SecureRandom.base64(12)
+    super
+  end
+
+  # POST /resource/sign_in
+  # def create
+  #   super
+  # end
+
+  # DELETE /resource/sign_out
+  # def destroy
+  #   super
+  # end
+
+  # POST /users/nostr_login
+  def nostr_login
+    signed_event = Nostr::Event.new(**nostr_event_from_params)
+
+    is_valid_sig  = signed_event.verify_signature
+    is_valid_auth = NostrManager::VerifyAuth.call(
+      event: signed_event,
+      challenge: session[:shared_secret]
+    )
+
+    session[:shared_secret] = nil
+
+    unless is_valid_sig && is_valid_auth
+      flash[:alert] = "Login verification failed"
+      http_status :unauthorized and return
+    end
+
+    user = LdapManager::FetchUserByNostrKey.call(pubkey: signed_event.pubkey)
+
+    if user.present?
+      set_flash_message!(:notice, :signed_in)
+      sign_in("user", user)
+      render json: { redirect_url: after_sign_in_path_for(user) }, status: :ok
+    else
+      flash[:alert] = "Failed to find your account. Nostr login may be disabled."
+      http_status :unauthorized
+    end
+  end
+
+  protected
+
+    def set_flash_message(key, kind, options = {})
+      # Hide flash message after redirecting from a signin route while logged in
+      super unless key == :alert && kind == "already_authenticated"
+    end
+
+  # If you have extra params to permit, append them to the sanitizer.
+  # def configure_sign_in_params
+  #   devise_parameter_sanitizer.permit(:sign_in, keys: [:attribute])
+  # end
+end