$gcloud app logs tail -s dev-goodhub-server
bundler: failed to load command: rackup (/workspace/.bundle/gems/ruby/2.7.0/bin/rackup)

entrypoint: bundle exec rails server Puma -p $PORT

/layers/google.ruby.bundle/gems/.bundle/gems/ruby/2.7.0/gems/thor-1.1.0/lib/thor/base.rb:525:in `handle_argument_error': ERROR: "rails server" was called with arguments ["Puma", "--p", "8081"] (Thor::InvocationError)
Usage: "rails server -u [thin/puma/webrick] [options]"

entrypoint: bundle exec rails server -u Puma -p $PORT

An error occurred while installing grpc (1.41.0), and Bundler cannot continue.

In Gemfile:
  appengine was resolved to 0.6.0, which depends on
    stackdriver was resolved to 0.21.1, which depends on
      google-cloud-error_reporting was resolved to 0.42.1, which depends on
google-cloud-error_reporting-v1beta1 was resolved to 0.4.2, which
depends on
          gapic-common was resolved to 0.6.0, which depends on
            googleapis-common-protos was resolved to 1.3.12, which depends on
              grpc

gem 'grpc'

/layers/google.ruby.bundle/gems/.bundle/gems/ruby/2.7.0/gems/zeitwerk-2.4.2/lib/zeitwerk/kernel.rb:34:in `require': cannot load such file -- listen (LoadError)

$ bundler: failed to load command: rails (/workspace/.bundle/gems/ruby/2.7.0/bin/rails)
$  Bundler::GemNotFound: Could not find ffi-1.15.0 in any of the sources

Process terminated because the request deadline was exceeded. Please ensure that your HTTP server is listening for requests on 0.0.0.0 and on the port defined by the PORT environment variable. (Error code 123)

// before
entrypoint: bundle exec rails server -u Puma -p 3000

// after
entrypoint: bundle exec rails server -u Puma -p $PORT

"ActiveRecord::ConnectionNotEstablished (Unknown MySQL server host '/cloudsql/インスタンス名' (11)):"

$ docker-compose run web gem install grpc

Gem files will remain installed in /usr/local/bundle/gems/grpc-1.41.0 for inspection.
Results logged to /usr/local/bundle/extensions/aarch64-linux/2.7.0/grpc-1.41.0/gem_make.out
ERROR: 1