Webpacker configuration file not found - Rails 6.0.0

Question

I was trying to run "rails s" to run my server then I suddenly run into an error that says webpacker configuration not found.

Here's the info:

boot@noki-K54C:~/Desktop/app$ rails s
=> Booting Puma
=> Rails 6.0.0 application starting in development 
=> Run `rails server --help` for more startup options
RAILS_ENV=development environment is not defined in config/webpacker.yml, falling back to production environment
Exiting
<b>Traceback</b> (most recent call last):
    79: from bin/rails:3:in `&lt;main&gt;&apos;
    78: from bin/rails:3:in `load&apos;
    77: from /home/app/Desktop/jonabell/bin/spring:15:in `&lt;top (required)&gt;&apos;
    76: from /home/app/Desktop/jonabell/bin/spring:15:in `require&apos;
    75: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/binstub.rb:11:in `&lt;top (required)&gt;&apos;
    74: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/binstub.rb:11:in `load&apos;
    73: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/bin/spring:49:in `&lt;top (required)&gt;&apos;
    72: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client.rb:30:in `run&apos;
    71: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/command.rb:7:in `call&apos;
    70: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/rails.rb:28:in `call&apos;
    69: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/rails.rb:28:in `load&apos;
    68: from /home/app/Desktop/jonabell/bin/rails:9:in `&lt;top (required)&gt;&apos;
    67: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `require&apos;
    66: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:291:in `load_dependency&apos;
    65: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `block in require&apos;
    64: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require&apos;
    63: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require_with_bootsnap_lfi&apos;
    62: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in `register&apos;
    61: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `block in require_with_bootsnap_lfi&apos;
    60: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `require&apos;
    59: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands.rb:18:in `&lt;main&gt;&apos;
    58: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/command.rb:46:in `invoke&apos;
    57: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/command/base.rb:65:in `perform&apos;
    56: from /home/app/.rvm/gems/ruby-2.6.0/gems/thor-0.20.3/lib/thor.rb:387:in `dispatch&apos;
    55: from /home/app/.rvm/gems/ruby-2.6.0/gems/thor-0.20.3/lib/thor/invocation.rb:126:in `invoke_command&apos;
    54: from /home/app/.rvm/gems/ruby-2.6.0/gems/thor-0.20.3/lib/thor/command.rb:27:in `run&apos;
    53: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands/server/server_command.rb:138:in `perform&apos;
    52: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands/server/server_command.rb:138:in `tap&apos;
    51: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands/server/server_command.rb:147:in `block in perform&apos;
    50: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands/server/server_command.rb:37:in `start&apos;
    49: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/commands/server/server_command.rb:77:in `log_to_stdout&apos;
    48: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/server.rb:354:in `wrapped_app&apos;
    47: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/server.rb:219:in `app&apos;
    46: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/server.rb:319:in `build_app_and_options_from_config&apos;
    45: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/builder.rb:40:in `parse_file&apos;
    44: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/builder.rb:49:in `new_from_string&apos;
    43: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/builder.rb:49:in `eval&apos;
    42: from config.ru:in `&lt;main&gt;&apos;
    41: from config.ru:in `new&apos;
    40: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/builder.rb:55:in `initialize&apos;
    39: from /home/app/.rvm/gems/ruby-2.6.0/gems/rack-2.0.7/lib/rack/builder.rb:55:in `instance_eval&apos;
    38: from config.ru:3:in `block in &lt;main&gt;&apos;
    37: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:48:in `require_relative&apos;
    36: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `require&apos;
    35: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:291:in `load_dependency&apos;
    34: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `block in require&apos;
    33: from /home/app/.rvm/gems/ruby-2.6.0/gems/zeitwerk-2.1.10/lib/zeitwerk/kernel.rb:23:in `require&apos;
    32: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require&apos;
    31: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require_with_bootsnap_lfi&apos;
    30: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in `register&apos;
    29: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `block in require_with_bootsnap_lfi&apos;
    28: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `require&apos;
    27: from /home/app/Desktop/jonabell/config/environment.rb:5:in `&lt;main&gt;&apos;
    26: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/application.rb:363:in `initialize!&apos;
    25: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/initializable.rb:60:in `run_initializers&apos;
    24: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:205:in `tsort_each&apos;
    23: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:226:in `tsort_each&apos;
    22: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:347:in `each_strongly_connected_component&apos;
    21: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:347:in `call&apos;
    20: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:347:in `each&apos;
    19: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:349:in `block in each_strongly_connected_component&apos;
    18: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:431:in `each_strongly_connected_component_from&apos;
    17: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component&apos;
    16: from /usr/share/rvm/rubies/ruby-2.6.0/lib/ruby/2.6.0/tsort.rb:228:in `block in tsort_each&apos;
    15: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/initializable.rb:61:in `block in run_initializers&apos;
    14: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/initializable.rb:32:in `run&apos;
    13: from /home/app/.rvm/gems/ruby-2.6.0/gems/railties-6.0.0/lib/rails/initializable.rb:32:in `instance_exec&apos;
    12: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/railtie.rb:84:in `block in &lt;class:Engine&gt;&apos;
    11: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker.rb:27:in `bootstrap&apos;
    10: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/commands.rb:14:in `bootstrap&apos;
     9: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/manifest.rb:18:in `refresh&apos;
     8: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/manifest.rb:83:in `load&apos;
     7: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:47:in `public_manifest_path&apos;
     6: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:43:in `public_output_path&apos;
     5: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:39:in `public_path&apos;
     4: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:80:in `fetch&apos;
     3: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:84:in `data&apos;
     2: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:88:in `load&apos;
     1: from /home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:88:in `read&apos;
/home/app/.rvm/gems/ruby-2.6.0/gems/webpacker-4.0.7/lib/webpacker/configuration.rb:88:in `read&apos;: <b>No such file or directory @ rb_sysopen - /home/app/Desktop/jonabell/config/webpacker.yml (</b><u style="text-decoration-style:single"><b>Errno::ENOENT</b></u><b>)</b>
    78: from bin/rails:3:in `&lt;main&gt;&apos;
    77: from bin/rails:3:in `load&apos;
    76: from /home/app/Desktop/jonabell/bin/spring:15:in `&lt;top (required)&gt;&apos;
    75: from /home/app/Desktop/jonabell/bin/spring:15:in `require&apos;
    74: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/binstub.rb:11:in `&lt;top (required)&gt;&apos;
    73: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/binstub.rb:11:in `load&apos;
    72: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/bin/spring:49:in `&lt;top (required)&gt;&apos;
    71: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client.rb:30:in `run&apos;
    70: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/command.rb:7:in `call&apos;
    69: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/rails.rb:28:in `call&apos;
    68: from /home/app/.rvm/gems/ruby-2.6.0/gems/spring-2.1.0/lib/spring/client/rails.rb:28:in `load&apos;
    67: from /home/app/Desktop/jonabell/bin/rails:9:in `&lt;top (required)&gt;&apos;
    66: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `require&apos;
    65: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:291:in `load_dependency&apos;
    64: from /home/app/.rvm/gems/ruby-2.6.0/gems/activesupport-6.0.0/lib/active_support/dependencies.rb:325:in `block in require&apos;
    63: from /home/app/.rvm/gems/ruby-2.6.0/gems/bootsnap-1.4.5/li

Answer 1

Since Rails 6, Webpacker is the default JavaScript compiler. So you'll also have to set it up before starting your Rails server.

1. Install yarn using your OS package manager, or take a look at https://yarnpkg.com/en/docs/install
2. Set it up rails webpacker:install
3. Make sure all packages are up to date yarn install --check-files
4. Start your Rails server rails s

Enjoy!