uninitialized constant MailPreview

[adamwong246]

/Users/r625503/Programming/projectv/config/routes.rb:4:in `block in <top (required)>': uninitialized constant MailPreview (NameError)
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/actionpack-3.2.16/lib/action_dispatch/routing/route_set.rb:285:in `instance_exec'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/actionpack-3.2.16/lib/action_dispatch/routing/route_set.rb:285:in `eval_block'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/actionpack-3.2.16/lib/action_dispatch/routing/route_set.rb:263:in `draw'
    from /Users/r625503/Programming/projectv/config/routes.rb:1:in `<top (required)>'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/bundler/gems/rails-dev-boost-3e25b06c5c53/lib/rails_development_boost/loadable_patch.rb:14:in `load'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:40:in `each'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:40:in `load_paths'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:16:in `reload!'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:26:in `block in updater'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/activesupport-3.2.16/lib/active_support/file_update_checker.rb:78:in `call'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/activesupport-3.2.16/lib/active_support/file_update_checker.rb:78:in `execute'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:27:in `updater'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application/finisher.rb:66:in `block in <module:Finisher>'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/initializable.rb:30:in `instance_exec'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/initializable.rb:30:in `run'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/initializable.rb:55:in `block in run_initializers'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/initializable.rb:54:in `each'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/initializable.rb:54:in `run_initializers'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/application.rb:136:in `initialize!'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/railtie/configurable.rb:30:in `method_missing'
    from /Users/r625503/Programming/projectv/config/environment.rb:5:in `<top (required)>'
    from /Users/r625503/Programming/projectv/config.ru:3:in `block in <main>'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/builder.rb:51:in `instance_eval'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/builder.rb:51:in `initialize'
    from /Users/r625503/Programming/projectv/config.ru:in `new'
    from /Users/r625503/Programming/projectv/config.ru:in `<main>'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/builder.rb:40:in `eval'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/builder.rb:40:in `parse_file'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/server.rb:200:in `app'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/commands/server.rb:46:in `app'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/server.rb:304:in `wrapped_app'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/rack-1.4.5/lib/rack/server.rb:254:in `start'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/commands/server.rb:70:in `start'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/commands.rb:55:in `block in <top (required)>'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/commands.rb:50:in `tap'
    from /Users/r625503/.rvm/gems/ruby-2.0.0-p195/gems/railties-3.2.16/lib/rails/commands.rb:50:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'

Not sure why though. The gems in the gemfile and I copy-pasted the mounting call into routes.

ruby is at 2.0.0 and rails is at 3.2.16

[wojtekmach]

@adamwong246 what's the name of your mailer? README instructions are assuming it's MailPreview, if it's something different then you have to change the name of the class you're mounting in routes.

[zakelfassi]

as @wojtekmach mentioned, you should set the router -explicitely- as follows:

mount YourMailPreviewClassName, :at => 'your_endpoint'

(this should be closed as it's not a mail_view issue.)

[andreapavoni]

I've got the same error. Fixed by specifying to load the lib/ path in config/application.rb:

# ...
   config.autoload_paths += %W(#{config.root}/lib)
# ...