enforce readonly on create/update endpoints

app/controllers/ajax/answer_controller.rb

@@ -5,6 +5,8 @@ require "cgi"
 class Ajax::AnswerController < AjaxController
   include SocialHelper
 
+  before_action :not_readonly!, except: %i[destroy]
+
   def create
     params.require :id
     params.require :answer

app/controllers/ajax/comment_controller.rb

@@ -1,4 +1,6 @@
 class Ajax::CommentController < AjaxController
+  before_action :not_readonly!, except: %i[destroy]
+
   def create
     params.require :answer
     params.require :comment

app/controllers/ajax/list_controller.rb

@@ -2,6 +2,7 @@
 
 class Ajax::ListController < AjaxController
   before_action :authenticate_user!
+  before_action :not_readonly!, except: %i[destroy]
 
   def create
     params.require :name

app/controllers/ajax/question_controller.rb

@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 class Ajax::QuestionController < AjaxController
+  before_action :not_readonly!, except: %i[destroy]
+
   def create
     params.require :question
     params.require :anonymousQuestion

app/controllers/answer_controller.rb

@@ -2,6 +2,7 @@
 
 class AnswerController < ApplicationController
   before_action :authenticate_user!, only: %i[pin unpin]
+  before_action :not_readonly!, except: %i[show]
 
   include TurboStreamable
 

app/controllers/application_controller.rb

@@ -78,4 +78,29 @@ class ApplicationController < ActionController::Base
       Sentry.set_user({ ip_address: request.remote_ip })
     end
   end
+
+  # use this as a before_action to avoid anything happening when the site is in
+  # read-only mode
+  #
+  # useful only in: `AjaxController`s, or `TurboStreamable`s as the exception
+  # is rescued there
+  def not_readonly!
+    return unless Retrospring::Config.readonly?
+
+    raise Errors::ReadOnlyMode
+  end
+
+  # use this as a before_action to avoid anything happening when the site is in
+  # read-only mode
+  #
+  # useful anywhere else `not_readonly!` can't be used.  it sets the error
+  # flash appropriately and renders the view given in `view_name`
+  def not_readonly_flash!(view_name)
+    return unless Retrospring::Config.readonly?
+
+    flash[:error] = t("errors.read_only_mode")
+    render view_name
+
+    false
+  end
 end

app/controllers/inbox_controller.rb

@@ -18,6 +18,8 @@ class InboxController < ApplicationController
   end
 
   def create
+    return redirect_to inbox_path if Retrospring::Config.readonly?
+
     question = Question.create!(content:             QuestionGenerator.generate,
                                 author_is_anonymous: true,
                                 author_identifier:   "justask",

app/controllers/reactions_controller.rb

@@ -4,6 +4,7 @@ class ReactionsController < ApplicationController
   include TurboStreamable
 
   before_action :authenticate_user!, only: %w[create destroy]
+  before_action :not_readonly!, except: %i[index]
 
   turbo_stream_actions :create, :destroy
 

app/controllers/relationships_controller.rb

@@ -4,6 +4,7 @@ class RelationshipsController < ApplicationController
   include TurboStreamable
 
   before_action :authenticate_user!
+  before_action :not_readonly!
 
   turbo_stream_actions :create, :destroy
 

app/controllers/settings/profile_controller.rb

@@ -2,6 +2,7 @@
 
 class Settings::ProfileController < ApplicationController
   before_action :authenticate_user!
+  before_action -> { not_readonly_flash!(:edit) }, only: %i[update]
 
   def edit; end
 

app/controllers/settings/profile_picture_controller.rb

@@ -2,6 +2,7 @@
 
 class Settings::ProfilePictureController < ApplicationController
   before_action :authenticate_user!
+  before_action -> { not_readonly_flash!("settings/profile/edit") }, only: %i[update]
 
   def update
     user_attributes = params.require(:user).permit(:show_foreign_themes, :profile_picture_x, :profile_picture_y, :profile_picture_w, :profile_picture_h,

app/controllers/settings/theme_controller.rb

@@ -4,6 +4,7 @@ class Settings::ThemeController < ApplicationController
   include ThemeHelper
 
   before_action :authenticate_user!
+  before_action -> { not_readonly_flash!(:edit) }, only: %i[update destroy]
 
   def edit; end
 

app/controllers/subscriptions_controller.rb

@@ -4,6 +4,7 @@ class SubscriptionsController < ApplicationController
   include TurboStreamable
 
   before_action :authenticate_user!
+  before_action :not_readonly!
 
   turbo_stream_actions :create, :destroy
 

config/locales/errors.en.yml

@@ -23,6 +23,8 @@ en:
     blocking_self: "You cannot block yourself"
     muting_self: "You cannot mute yourself"
 
+    read_only_mode: "The website is in read-only mode."
+
     not_found: "That does not exist"
     user_not_found: "User not found"
 

lib/errors.rb

@@ -20,9 +20,23 @@ module Errors
   end
 
   class BadRequest < Base
-    def status
+    def status = 400
-      400
   end
+
+  class NotAuthorized < Base
+    def status = 401
+  end
+
+  class Forbidden < Base
+    def status = 403
+  end
+
+  class NotFound < Base
+    def status = 404
+  end
+
+  class MethodNotAllowed < Base
+    def status = 405
   end
 
   class InvalidBanDuration < BadRequest
@@ -31,12 +45,6 @@ module Errors
   class QuestionTooLong < BadRequest
   end
 
-  class Forbidden < Base
-    def status
-      403
-    end
-  end
-
   class SelfAction < Forbidden
   end
 
@@ -46,18 +54,6 @@ module Errors
   class FollowingSelf < SelfAction
   end
 
-  class NotFound < Base
-    def status
-      404
-    end
-  end
-
-  class NotAuthorized < Base
-    def status
-      401
-    end
-  end
-
   class UserNotFound < NotFound
   end
 
@@ -125,4 +121,7 @@ module Errors
 
   class MutingSelf < SelfAction
   end
+
+  class ReadOnlyMode < MethodNotAllowed
+  end
 end