This can happen during development when classes without automatic reloading are pointing to classes with automatic reloading. E.g. some class in lib is calling Model.static_method.

Workaround A

Stop referencing autoloaded classes from static files. If you can't, see workaround B and C.

Workaround B

Make sure the offending file (the one referencing the autoloaded class) is autoloaded, too. You may do this:

# config/application.rb

  config.paths.add 'offending/file/parent/directory', eager_load: true

Workaround C

Make sure you're not caching instances of the erroring class (e.g. with Thread.current).

Workaround D

If possible, make the autoloaded class static by moving it out of Rails' load path.

Henning Koch

makandra.com

Say thanks20

Last edit

Over 4 years ago

Dominik Schöler

Keywords

cache, classes, class

License

Source code in this card is licensed under the MIT License.

Async control flow in JavaScript: Promises, Microtasks, async/await

Slides for Henning's talk on Sep 21st 2017.

Understanding sync vs. async control flow

Talking to synchronous (or "blocking") API

print('script start')
html = get('/foo')
print(html)
print('s...

Delivering Carrierwave attachments to authorized users only

Preparation

To attach files to your records, you will need a new database column representing the filename of the file. To do this, add a new migration (rails g migration <name>) with the following content:

class AddAttachmentToNotes...

Posted by Henning Koch to makandra dev (2010-08-25 12:21)

Fixing "A copy of Klass has been removed from the module tree but is still active"