hide detailed exception info in upload status (#3804)

app/logical/upload_service/preprocessor.rb

@@ -111,6 +111,7 @@ class UploadService
 
       # we went through a lot of trouble normalizing the source,
       # so don't overwrite it with whatever the user provided
+      pred.source = "" if pred.source.nil?
       pred.attributes = self.params.except(:source)
 
       # if a file was uploaded after the preprocessing occurred,

app/presenters/upload_presenter.rb

@@ -9,6 +9,9 @@ class UploadPresenter < Presenter
       dup_post_id = $1
       template.link_to(@upload.status.gsub(/error: RuntimeError - /, ""), template.__send__(:post_path, dup_post_id))
 
+    when /\Aerror: /
+      @upload.status.gsub(/DETAIL:.+/m, "...")
+
     else
       @upload.status
     end