Rails console in production: NameError: uninitialized constant - ruby-on-rails

Question

I have a rails app (rails 5). In development, everything work, when i use
rails console
And enter an instruction, for example User.all , it's working.
In production, my app work perfectly, no problems, no errors, but when i use rails console production and enter for example User.all i have an error :
NameError: uninitialized constant User
from (irb):2
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/console.rb:65:in `start'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/console_helper.rb:9:in `start'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:78:in `console'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands.rb:18:in `<top (required)>'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `require'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `block in require'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:259:in `load_dependency'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `require'
from /home/alexandre/tcheen/bin/rails:9:in `<top (required)>'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/commands/rails.rb:6:in `load'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/commands/rails.rb:6:in `call'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/command_wrapper.rb:38:in `call'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:191:in `block in serve'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:161:in `fork'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:161:in `serve'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:131:in `block in run'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:125:in `loop'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application.rb:125:in `run'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/spring-1.7.2/lib/spring/application/boot.rb:19:in `<top (required)>'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /home/alexandre/.rbenv/versions/2.3.1/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from -e:1:in `<main>'
I have the same problem with all my classes, but i repeat, the application work perfectly.
I develop on Mac OS and the app run in production on debian 8.
My models are correctly named i verified.
Thanks

Answer 1

I had this problem and realized it happened after I made a tweak to one of my job files.
What fixed it was restarting the spring loader. Just run
spring stop
Then the next time you run the rails console it should load things as normal.

Answer 2

I had this same issue, rewolf's answer above solved it for me temporarily.
Just to add to his answer:
After stopping the spring gem by running the command below
spring stop
You can also fix this issue permanently by upspringing (removing the spring gem from) your bin/ executables:
bin/spring binstub --remove --all
Or
spring binstub --remove --all
You can now run the command below to get into rails console in production
rails c --environment=production
Also, to avoid this from occurring in subsequent occasions endeavour to make sure that the spring gem is only present in development and test groups in your Gemfile.
Moreso, when you're in production make sure you always provide the --without development test argument to the bundle install command
bundle install --without development test
and not the usual or common
bundle install
Please note: As an indication, whenever you run the command rails c or rails console and you see the output below:
Running via Spring preloader in process 26651
WARNING: Spring is running in production. To fix this make sure the spring gem is only present in development and test groups in your Gemfile and make sure you always use bundle install --without development test in production
It's an indication that the spring gem is running in your production environment, and it should be stopped or removed entirely from your bin executables.
That's all.
I hope this helps