Added exception handling to paperclip:refresh:thumbnails rake task.

https://github.com/thoughtbot/paperclip/issues/760

lib/tasks/paperclip.rake

@@ -16,6 +16,10 @@ module Paperclip
         klass.attachment_definitions.keys
       end
     end
+
+    def self.log_error(error)
+      puts error
+    end
   end
 end
 
@@ -31,10 +35,16 @@ namespace :paperclip do
       styles = (ENV['STYLES'] || ENV['styles'] || '').split(',').map(&:to_sym)
       names.each do |name|
         Paperclip.each_instance_with_attachment(klass, name) do |instance|
-          instance.send(name).reprocess!(*styles)
+          attachment = instance.send(name)
+          begin
+            attachment.reprocess!(*styles)
+          rescue Exception => e
+            Paperclip::Task.log_error("exception while processing #{klass} ID #{instance.id}:")
+            Paperclip::Task.log_error(" " + e.message + "\n")
+          end
           unless instance.errors.blank?
-            puts "errors while processing #{klass} ID #{instance.id}:"
-            puts " " + instance.errors.full_messages.join("\n ") + "\n"
+            Paperclip::Task.log_error("errors while processing #{klass} ID #{instance.id}:")
+            Paperclip::Task.log_error(" " + instance.errors.full_messages.join("\n ") + "\n")
           end
         end
       end

test/rake_test.rb

+require './test/helper'
+require 'rake'
+load './lib/tasks/paperclip.rake'
+
+class RakeTest < Test::Unit::TestCase
+  context "calling `rake paperclip:refresh:thumbnails`" do
+    setup do
+      rebuild_model
+      Paperclip::Task.stubs(:obtain_class).returns('Dummy')
+      @bogus_instance = Dummy.new
+      @bogus_instance.id = 'some_id'
+      @bogus_instance.avatar.stubs(:reprocess!)
+      @valid_instance = Dummy.new
+      @valid_instance.avatar.stubs(:reprocess!)
+      Paperclip::Task.stubs(:log_error)
+      Paperclip.stubs(:each_instance_with_attachment).multiple_yields @bogus_instance, @valid_instance
+    end
+    context "when there is an exception in reprocess!" do
+      setup do
+        @bogus_instance.avatar.stubs(:reprocess!).raises
+      end
+
+      should "catch the exception" do
+        assert_nothing_raised do
+          ::Rake::Task['paperclip:refresh:thumbnails'].execute
+        end
+      end
+
+      should "continue to the next instance" do
+        @valid_instance.avatar.expects(:reprocess!)
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the exception" do
+        exception_msg = 'Some Exception'
+        @bogus_instance.avatar.stubs(:reprocess!).raises(exception_msg)
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match exception_msg
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the class name" do
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match 'Dummy'
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the instance ID" do
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match "ID #{@bogus_instance.id}"
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+    end
+
+    context "when there is an error in reprocess!" do
+      setup do
+        @errors = mock('errors')
+        @errors.stubs(:full_messages).returns([''])
+        @errors.stubs(:blank?).returns(false)
+        @bogus_instance.stubs(:errors).returns(@errors)
+      end
+
+      should "continue to the next instance" do
+        @valid_instance.avatar.expects(:reprocess!)
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the error" do
+        error_msg = 'Some Error'
+        @errors.stubs(:full_messages).returns([error_msg])
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match error_msg
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the class name" do
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match 'Dummy'
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+      should "print the instance ID" do
+        Paperclip::Task.expects(:log_error).with do |str|
+          str.match "ID #{@bogus_instance.id}"
+        end
+        ::Rake::Task['paperclip:refresh:thumbnails'].execute
+      end
+
+    end
+  end
+end