add fetch controller

app/controllers/diaspora_federation/fetch_controller.rb

@@ -0,0 +1,36 @@
+require_dependency "diaspora_federation/application_controller"
+
+module DiasporaFederation
+  # this controller processes fetch requests
+  class FetchController < ApplicationController
+    # returns the fetched entity or a redirect
+    #
+    # GET /fetch/:type/:guid
+    def fetch
+      entity = fetch_public_entity
+      if entity
+        magic_env = create_magic_envelope(entity)
+        if magic_env
+          render xml: magic_env, content_type: "application/magic-envelope+xml"
+        else
+          redirect_to DiasporaFederation.callbacks.trigger(:fetch_person_url_to,
+                                                           entity.author, "/fetch/#{params[:type]}/#{params[:guid]}")
+        end
+      else
+        render nothing: true, status: 404
+      end
+    end
+
+    private
+
+    def fetch_public_entity
+      type = DiasporaFederation::Entity.entity_class(params[:type]).to_s.rpartition("::").last
+      DiasporaFederation.callbacks.trigger(:fetch_public_entity, type, params[:guid])
+    end
+
+    def create_magic_envelope(entity)
+      privkey = DiasporaFederation.callbacks.trigger(:fetch_private_key_by_diaspora_id, entity.author)
+      Salmon::MagicEnvelope.new(entity).envelop(privkey, entity.author) if privkey
+    end
+  end
+end

app/controllers/diaspora_federation/webfinger_controller.rb

@@ -13,7 +13,7 @@ module DiasporaFederation
     #
     # GET /.well-known/host-meta
     def host_meta
-      render body: WebfingerController.host_meta_xml, content_type: "application/xrd+xml"
+      render xml: WebfingerController.host_meta_xml, content_type: "application/xrd+xml"
     end
 
     # @deprecated this is the pre RFC 7033 webfinger
@@ -41,7 +41,7 @@ module DiasporaFederation
         render nothing: true, status: 404
       else
         logger.info "webfinger profile request for: #{person_wf.acct_uri}"
-        render body: person_wf.to_xml, content_type: "application/xrd+xml"
+        render xml: person_wf.to_xml, content_type: "application/xrd+xml"
       end
     end
 

config/routes.rb

@@ -4,6 +4,10 @@ DiasporaFederation::Engine.routes.draw do
     post "receive/users/:guid" => :private, :as => "receive_private"
   end
 
+  controller :fetch do
+    get "fetch/:type/:guid" => :fetch, :as => "fetch"
+  end
+
   controller :webfinger do
     get ".well-known/host-meta" => :host_meta,        :as => "host_meta"
     get "webfinger"             => :legacy_webfinger, :as => "legacy_webfinger"