Add twtxt support

app/controllers/accounts_controller.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 class AccountsController < ApplicationController
+  OFFSET        = 0
   PAGE_SIZE     = 20
   PAGE_SIZE_MAX = 200
 
@@ -20,17 +21,21 @@ def show
         expires_in(15.seconds, public: true, stale_while_revalidate: 30.seconds, stale_if_error: 1.hour) unless user_signed_in?
       end
 
-      format.rss do
+      format.any(:rss, :txt) do
         expires_in 1.minute, public: true
 
         limit     = params[:limit].present? ? [params[:limit].to_i, PAGE_SIZE_MAX].min : PAGE_SIZE
-        @statuses = filtered_statuses.without_reblogs.limit(limit)
+        offset    = params[:offset].present? ? params[:offset].to_i : OFFSET
+        @statuses = filtered_statuses.without_reblogs.limit(limit).offset(offset)
         @statuses = preload_collection(@statuses, Status)
       end
 
       format.json do
         expires_in 3.minutes, public: !(authorized_fetch_mode? && signed_request_account.present?)
-        render_with_cache json: @account, content_type: 'application/activity+json', serializer: ActivityPub::ActorSerializer, adapter: ActivityPub::Adapter
+        render_with_cache json: @account,
+                          content_type: 'application/activity+json',
+                          serializer: ActivityPub::ActorSerializer,
+                          adapter: ActivityPub::Adapter
       end
     end
   end
@@ -46,7 +51,7 @@ def filtered_statuses
   end
 
   def default_statuses
-    @account.statuses.not_local_only.distributable_visibility
+    @account.statuses.not_local_only.where(visibility: [:public, :unlisted])
   end
 
   def only_media_scope

app/views/accounts/show.txt.erb

@@ -0,0 +1,39 @@
+<% account_url = params[:tag].present? ? short_account_tag_url(@account, params[:tag]) : short_account_url(@account) %>
+# Twtxt is an open, distributed microblogging platform that
+# uses human-readable text files, common transport protocols,
+# and free software.
+#
+# Learn more about twtxt at https://github.com/buckket/twtxt
+#
+# The numeric value between the date and the status text (#...) is the id
+# of that toot, so you can easily find the URL of a toot.
+#
+# By default, you will only see the 20 most recent statuses.
+#
+# You can also set parameters "limit" and "offset" in your query string if
+# you want to fetch more statuses. Please note that you can only fetch up
+# to 200 statuses at a time.
+#
+# E.g. to get the latest 200 statuses:
+# <%= account_url %>.txt?limit=200
+#
+# E.g. to skip the latest 200 status, and fetch the 200 previous ones:
+# <%= account_url %>.txt?offset=200&limit=200
+#
+# nick        = @<%= @account.local_username_and_domain %>
+# url         = <%= account_url %>.txt
+# avatar      = <%= full_asset_url(@account.avatar.url(:original)) %>
+# description = <%= I18n.t('rss.descriptions.account', acct: @account.local_username_and_domain) %>
+
+<% @statuses.each do |status| %>
+<%   plain_text_status = (extract_status_plain_text status).gsub("\n", "\u2028") %>
+<%   status.ordered_media_attachments.each do |media| %>
+<%     media_url = full_asset_url(media.file.url(:original, false)) %>
+<%     media_description = media.description.nil? ? "" : media.description.gsub("\n", " ") %>
+<%     plain_text_status += " ![#{media_description}](#{media_url})" %>
+<%   end %>
+<%   if !plain_text_status.empty? %>
+<%     plain_text_status = " (\##{status.id}) #{plain_text_status}" %>
+<%=    status.created_at.rfc3339 %>	<%= plain_text_status %>
+<%   end %>
+<% end %>

config/initializers/mime_types.rb

@@ -2,6 +2,7 @@
 
 Mime::Type.register 'application/json', :json, %w(text/x-json application/jsonrequest application/jrd+json application/activity+json application/ld+json)
 Mime::Type.register 'text/xml',         :xml,  %w(application/xml application/atom+xml application/xrd+xml)
+Mime::Type.register 'text/plain',       :txt,  %w(text/plain)
 
 # WebP is not defined in Rack 2.2.
 Rack::Mime::MIME_TYPES['.webp'] = 'image/webp'