Ruby on Rails 4.1.8 Gem::LoadError for mysql2 gem

问题

I picked up a 4 year old project written in Ruby 2.1.3 and Rails 4.1.8.

Very few of the gems were versioned but I've managed to get the project running locally by installing mysql2 0.3.20 as suggested in multiple other threads. Doing this required me to (on MacOS) downgrade openssl and mysql with brew install mysql@57 and brew install openssl@10.

I could then install mysql2 with by passing the correct libraries to it: gem install mysql2 -v 0.3.20 -- --with-mysql-config=/usr/local/opt/mysql@5.7/bin/mysql_config --with-ldflags=-L/usr/local/opt/openssl@1.0/lib --with-cppflags=-I/usr/local/opt/openssl@1.0/include

Everything works locally, all good.

I'm trying to deploy this project with Dokku on a Debian instance. Here's the readout from the push to dokku master including the error thrown when starting the Rails server:

Dev@Jordans-MacBook-Pro ~/runritewinDB2020 (master) $ git push dokku master
Enumerating objects: 1608, done.
Counting objects: 100% (1608/1608), done.
Delta compression using up to 4 threads
Compressing objects: 100% (975/975), done.
Writing objects: 100% (1608/1608), 14.90 MiB | 1.19 MiB/s, done.
Total 1608 (delta 611), reused 1520 (delta 554)
remote: Resolving deltas: 100% (611/611), done.
-----> Cleaning up...
-----> Building runrite from dockerfile...
remote: build context to Docker daemon  51.88MB
Step 1/17 : FROM ruby:2.1.3
 ---> e1f10119c75a
Step 2/17 : RUN apt-get install -y libpq-dev
 ---> Using cache
 ---> 18e44db81b01
Step 3/17 : RUN apt-get install -y libxml2-dev libxslt1-dev
 ---> Using cache
 ---> b753197bec2f
Step 4/17 : ENV RAILS_ENV production
 ---> Using cache
 ---> fe632f7c4b4f
Step 5/17 : ENV RACK_ENV production
 ---> Using cache
 ---> ebeb94b2a120
Step 6/17 : ENV RACK production
 ---> Using cache
 ---> 98942a7c066f
Step 7/17 : ENV DB_URL mysql://mysql:f7a080fdf10779b0@dokku-mysql-runrite-production:3306/runrite_production
 ---> Using cache
 ---> 0feff73f3952
Step 8/17 : ENV APP_HOME /myapp
 ---> Using cache
 ---> 472864c3692a
Step 9/17 : RUN mkdir $APP_HOME
 ---> Using cache
 ---> 8cf938f4771b
Step 10/17 : WORKDIR $APP_HOME
 ---> Using cache
 ---> 83c835ef8ba6
Step 11/17 : ADD Gemfile* $APP_HOME/
 ---> 687cafb12ca9
Step 12/17 : RUN bundle install
 ---> Running in df7a7d1b74a3
Don't run Bundler as root. Bundler can ask for sudo if it is needed, and
installing your bundle as root will break this application for all non-root
users on this machine.
Fetching source index from https://rubygems.org/
Fetching git://github.com/activerecord-hackery/polyamorous.git
Fetching git://github.com/activeadmin/activeadmin.git
Fetching https://github.com/stripe/stripe-ruby
Installing rake 10.4.2
Installing CFPropertyList 2.2.8
Installing i18n 0.7.0
Installing json 1.8.3
Installing minitest 5.8.0
Installing thread_safe 0.3.5
Installing tzinfo 1.2.2
Installing activesupport 4.1.8
Installing builder 3.2.2
Installing erubis 2.7.0
Installing actionview 4.1.8
Installing rack 1.5.5
Installing rack-test 0.6.3
Installing actionpack 4.1.8
Installing mime-types 2.6.1
Installing mail 2.6.3
Installing actionmailer 4.1.8
Installing activemodel 4.1.8
Installing active_model_serializers 0.9.0
Installing arbre 1.0.3
Installing sass 3.2.19
Installing thor 0.19.1
Installing bourbon 3.2.4
Installing coffee-script-source 1.9.1.1
Installing execjs 2.6.0
Installing coffee-script 2.4.1
Installing railties 4.1.8
Installing coffee-rails 4.0.1
Installing formtastic 3.1.3
Installing formtastic_i18n 0.4.1
Installing has_scope 0.6.0
Installing responders 1.1.2
Installing inherited_resources 1.6.0
Installing jquery-rails 3.1.3
Installing jquery-ui-rails 5.0.5
Installing kaminari 0.16.3
Installing arel 5.0.1.20140414130214
Installing activerecord 4.1.8
Using bundler 1.7.4
Installing hike 1.2.3
Installing multi_json 1.11.2
Installing tilt 1.4.1
Installing sprockets 2.12.4
Installing sprockets-rails 2.3.2
Installing rails 4.1.8
Using polyamorous 1.3.3 from git://github.com/activerecord-hackery/polyamorous.git (at master)
Installing ransack 1.7.0
Installing sass-rails 4.0.5
Using activeadmin 1.0.0.pre1 from git://github.com/activeadmin/activeadmin.git (at master)
Installing addressable 2.3.6
Installing multipart-post 2.0.0
Installing avocado-docs 3.0.7
Installing mini_portile 0.6.0
Installing nokogiri 1.6.3.1
Installing aws-sdk-v1 1.56.0
Installing aws-sdk 1.56.0
Installing bcrypt 3.1.7
Installing coderay 1.1.0
Installing better_errors 2.0.0
Installing debug_inspector 0.0.2
Installing binding_of_caller 0.7.2
Installing columnize 0.8.9
Installing debugger-linecache 1.2.0
Installing slop 3.6.0
Installing byebug 3.5.1
Installing cancancan 1.9.2
Installing colorize 0.7.7
Installing net-ssh 2.9.2
Installing net-scp 1.2.1
Installing sshkit 1.7.1
Installing capistrano 3.4.0
Installing capistrano-bundler 1.1.3
Installing capistrano-rails 1.1.2
Installing capistrano-rbenv 2.0.2
Installing capistrano3-unicorn 0.2.1
Installing xpath 2.0.0
Installing capybara 2.4.4
Installing carrierwave 0.10.0
Installing streamio-ffmpeg 1.0.0
Installing carrierwave-video 0.5.6
Installing hitimes 1.2.2
Installing timers 4.0.1
Installing celluloid 0.16.0
Installing chartkick 1.3.2
Installing commonjs 0.2.7
Installing safe_yaml 1.0.4
Installing crack 0.4.2
Installing css_parser 1.3.7
Installing database_cleaner 1.3.0
Installing orm_adapter 0.5.0
Installing warden 1.2.3
Installing devise 3.4.0
Installing devise_invitable 1.4.1
Installing interception 0.5
Installing did_you_mean 0.9.6
Installing diff-lcs 1.2.5
Installing docile 1.1.5
Installing unf_ext 0.0.7.1
Installing unf 0.1.4
Installing domain_name 0.5.24
Installing launchy 2.4.2
Installing email_spec 1.6.0
Installing enumerize 0.9.0
Installing exception_notification 4.1.1
Installing excon 0.42.1
Installing fabrication 2.11.3
Installing faker 1.4.3
Installing faraday 0.9.0
Installing faraday_middleware 0.9.1
Installing ffi 1.9.6
Installing figaro 1.0.0
Installing fission 0.5.0
Installing formatador 0.2.5
Installing fog-core 1.27.2
Installing fog-xml 0.1.1
Installing fog-atmos 0.1.0
Installing fog-json 1.0.0
Installing inflecto 0.0.2
Installing fog-brightbox 0.7.1
Installing fog-ecloud 0.0.2
Installing fog-profitbricks 0.0.1
Installing fog-radosgw 0.0.3
Installing fog-sakuracloud 0.1.1
Installing fog-softlayer 0.3.25
Installing fog-storm_on_demand 0.1.0
Installing fog-terremark 0.0.3
Installing fog-vmfusion 0.0.1
Installing fog-voxel 0.0.2
Installing ipaddress 0.8.0
Installing fog 1.26.0
Installing font-awesome-rails 4.2.0.0
Installing rb-fsevent 0.9.4
Installing rb-inotify 0.9.5
Installing listen 2.7.11
Installing lumberjack 1.0.9
Installing method_source 0.8.2
Installing pry 0.10.1
Installing guard 2.6.1
Installing guard-bundler 2.0.0
Installing guard-rails 0.6.0
Installing rspec-support 3.1.2
Installing rspec-core 3.1.7
Installing rspec-expectations 3.1.2
Installing rspec-mocks 3.1.3
Installing rspec 3.1.0
Installing guard-rspec 4.3.1
Installing hashie 3.3.1
Installing htmlentities 4.3.4
Installing http-cookie 1.0.2
Installing multi_xml 0.5.5
Installing httparty 0.13.1
Installing jbuilder 2.2.3
Installing jwt 1.0.0
Installing kgio 2.9.2
Installing less 2.6.0
Installing less-rails 2.6.0
Installing libv8 3.16.14.7
Installing mysql2 0.3.20
Installing netrc 0.10.3
Installing oauth 0.4.7
Installing oauth2 1.0.0
Installing omniauth 1.2.2
Installing omniauth-oauth2 1.2.0
Installing omniauth-facebook 2.0.0
Installing omniauth-oauth 1.0.1
Installing omniauth-twitter 1.1.0
Installing owlcarousel-rails 1.1.3.3
Installing paper_trail 3.0.6
Installing premailer 1.8.6
Installing premailer-rails 1.8.2
Installing pry-byebug 2.0.0
Installing pry-rails 0.3.2
Installing puma 2.13.3
Installing pundit 0.3.0
Installing pushmeup 0.3.0
Installing rails-observers 0.1.2
Installing raindrops 0.13.0
Installing rb-fchange 0.0.6
Installing ref 1.0.5
Installing rest-client 1.8.0
Installing rmagick 2.15.0
Installing rspec-rails 3.1.0
Installing shoulda-context 1.2.1
Installing shoulda-matchers 2.7.0
Installing shoulda 3.5.0
Installing simple_form 3.1.0
Installing simplecov-html 0.8.0
Installing simplecov 0.9.1
Installing spring 1.1.3
Using stripe 1.26.0 from https://github.com/stripe/stripe-ruby (at master)
Installing therubyracer 0.12.1
Installing twitter-bootstrap-rails 3.2.0
Installing uglifier 2.5.3
Installing unicorn 4.8.3
Installing webmock 1.19.0
Installing yarjuf 2.0.0
Your bundle is complete!
It was installed into /usr/local/bundle
Post-install message from capistrano:
Capistrano 3.1 has some breaking changes. Please check the CHANGELOG: #Edited for shortened URL

If you're upgrading Capistrano from 2.x, we recommend to read the upgrade guide: # Remove shortened URL

The `deploy:restart` hook for passenger applications is now in a separate gem called capistrano-passenger.  Just add it to your Gemfile and require it in your Capfile.
Post-install message from httparty:
When you HTTParty, you must party hard!
Post-install message from twitter-bootstrap-rails:
Important: You may need to add a javascript runtime to your Gemfile in order for bootstrap's LESS files to compile to CSS.

**********************************************

ExecJS supports these runtimes:

therubyracer - Google V8 embedded within Ruby

therubyrhino - Mozilla Rhino embedded within JRuby

Node.js

Apple JavaScriptCore - Included with Mac OS X

Microsoft Windows Script Host (JScript)

**********************************************
Removing intermediate container df7a7d1b74a3
 ---> cab4f5704fc6
Step 13/17 : ADD . $APP_HOME
 ---> ffda2dba11f3
Step 14/17 : RUN bundle exec rails server
 ---> Running in 3079acec1dac
=> Booting Puma
=> Rails 4.1.8 application starting in production on http://0.0.0.0:3000
=> Run `rails server -h` for more startup options
=> Notice: server is listening on all interfaces (0.0.0.0). Consider using 127.0.0.1 (--binding option)
=> Ctrl-C to shutdown server
Exiting
/usr/local/bundle/gems/activerecord-4.1.8/lib/active_record/connection_adapters/connection_specification.rb:190:in `rescue in spec': Specified 'mysql' for database adapter, but the gem is not loaded. Add `gem 'mysql'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord). (Gem::LoadError)
remote: from /usr/local/bundle/gems/activerecord-4.1.8/lib/active_record/connection_adapters/connection_specification.rb:187:in `spec'
remote: from /usr/local/bundle/gems/activerecord-4.1.8/lib/active_record/connection_handling.rb:50:in `establish_connection'
remote: from /usr/local/bundle/gems/activerecord-4.1.8/lib/active_record/railtie.rb:129:in `block (2 levels) in <class:Railtie>'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/lazy_load_hooks.rb:38:in `instance_eval'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/lazy_load_hooks.rb:38:in `execute_hook'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/lazy_load_hooks.rb:28:in `block in on_load'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/lazy_load_hooks.rb:27:in `each'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/lazy_load_hooks.rb:27:in `on_load'
remote: from /usr/local/bundle/gems/activerecord-4.1.8/lib/active_record/railtie.rb:118:in `block in <class:Railtie>'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/initializable.rb:30:in `instance_exec'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/initializable.rb:30:in `run'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/initializable.rb:55:in `block in run_initializers'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:226:in `block in tsort_each'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_component'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:427:in `each_strongly_connected_component_from'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:347:in `block in each_strongly_connected_component'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:345:in `each'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:345:in `call'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:345:in `each_strongly_connected_component'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:224:in `tsort_each'
remote: from /usr/local/lib/ruby/2.1.0/tsort.rb:205:in `tsort_each'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/initializable.rb:54:in `run_initializers'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/application.rb:300:in `initialize!'
remote: from /myapp/config/environment.rb:5:in `<top (required)>'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/dependencies.rb:247:in `require'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/dependencies.rb:247:in `block in require'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/dependencies.rb:232:in `load_dependency'
remote: from /usr/local/bundle/gems/activesupport-4.1.8/lib/active_support/dependencies.rb:247:in `require'
remote: from /myapp/config.ru:3:in `block in <main>'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/builder.rb:55:in `instance_eval'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/builder.rb:55:in `initialize'
remote: from /myapp/config.ru:in `new'
remote: from /myapp/config.ru:in `<main>'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/builder.rb:49:in `eval'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/builder.rb:49:in `new_from_string'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/builder.rb:40:in `parse_file'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/server.rb:277:in `build_app_and_options_from_config'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/server.rb:199:in `app'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/server.rb:50:in `app'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/server.rb:314:in `wrapped_app'
remote: from /usr/local/bundle/gems/rack-1.5.5/lib/rack/server.rb:250:in `start'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/server.rb:69:in `start'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/commands_tasks.rb:81:in `block in server'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/commands_tasks.rb:76:in `tap'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/commands_tasks.rb:76:in `server'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
remote: from /usr/local/bundle/gems/railties-4.1.8/lib/rails/commands.rb:17:in `<top (required)>'
remote: from bin/rails:4:in `require'
remote: from bin/rails:4:in `<main>'
remote: The command '/bin/sh -c bundle exec rails server' returned a non-zero code: 1

Dockerfile:

FROM ruby:2.1.3

RUN apt-get install -y libpq-dev

RUN apt-get install -y libxml2-dev libxslt1-dev

ENV RAILS_ENV production
ENV RACK_ENV production
ENV RACK production
ENV DB_URL mysql://mysql:f7a080fdf10779b0@dokku-mysql-runrite-production:3306/runrite_production

# for a JS runtime
RUN apt-get install -y nodejs

ENV APP_HOME /myapp
RUN mkdir $APP_HOME
WORKDIR $APP_HOME

ADD Gemfile* $APP_HOME/
RUN bundle install

ADD . $APP_HOME

RUN bundle exec rails server

database.yml:

development:
  adapter: mysql2
  database: runrite-web_development
  username: root
  password:
  host: localhost
  socket: /tmp/mysql.sock

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  adapter: mysql2
  database: db/runrite-web_test.sql
  username: root
  password:
  host: localhost
  socket: /tmp/mysql.sock
  timeout: 10000

production: &production
  adapter: mysql2
  encoding: utf8mb4
  charset: utf8mb4
  collation: utf8mb4_unicode_ci
  port: 3306
  database: runrite_production
  url: <%= ENV['DB_URL'] %>
  pool: 25

staging:
  <<: *production

Gemfile:

source 'https://rubygems.org'
ruby '2.1.3'

# TODO: put versions on most of these gems

# Core
gem 'rails', '4.1.8'
gem 'mysql2', '0.3.20'
# gem 'mysql'
# Deployment
gem 'capistrano', '~> 3.4.0', require: false
gem 'capistrano-rbenv', '~> 2.0'
gem 'capistrano-rails', '~> 1.1', require: false
gem 'capistrano-bundler', '~> 1.1', require: false
gem 'capistrano3-unicorn', require: false

gem "active_model_serializers"
gem "activeadmin", github: 'activeadmin'
gem "avocado-docs"
gem "aws-sdk"
# gem 'aws-healthcheck'
gem "cancancan"
gem "carrierwave"
gem "carrierwave-video"
gem "devise"
gem "devise_invitable"
gem 'enumerize'
gem "faraday"
gem "faraday_middleware"
gem 'fog'
gem 'font-awesome-rails'
gem "has_scope"
gem 'rmagick'
# gem 'mini_magick'
# gem 'imagemagick-binaries'
gem "omniauth"
gem "omniauth-facebook"
gem "omniauth-twitter"
gem "paper_trail"
gem "polyamorous", github: "activerecord-hackery/polyamorous"
gem "pundit"
gem "pushmeup"
gem "rails-observers"
gem "responders"
gem "therubyracer"
gem "less-rails" #Sprockets (what Rails 3.1 uses for its asset pipeline) supports LESS
gem "twitter-bootstrap-rails"
gem 'coffee-rails', '~> 4.0.0'
gem 'figaro'
gem 'jbuilder', '~> 2.0'
gem 'jquery-rails'
gem 'sass-rails', '~> 4.0.3'
gem 'spring', group: :development
gem 'simple_form'
# gem 'turbolinks'
gem 'uglifier', '>= 1.3.0'
gem 'unicorn'
gem 'yarjuf'
gem 'owlcarousel-rails'
gem "chartkick"
gem 'premailer-rails'
gem 'nokogiri'

# E-Commerce
gem 'stripe', :git => 'https://github.com/stripe/stripe-ruby'

group :development, :test do
  gem "rspec-rails"
  gem 'pry-rails'
  gem 'pry-byebug'
  gem 'shoulda'
  gem 'did_you_mean', '~> 0.9.4'
  gem "guard"
  gem "guard-rspec"
end

group :test do
  gem "capybara"
  gem "fabrication"
  gem "database_cleaner"
  gem "email_spec"
  gem 'simplecov', require: false
  gem 'webmock'
  # gem 'capybara-webkit'
  gem "faker"
end

group :development do
  gem "puma", '~> 2.13.3'
  gem "better_errors"
  gem "binding_of_caller"
  gem "guard-bundler"
  gem "guard-rails"
  gem "rb-fchange", require: false
  gem "rb-fsevent", require: false
  gem "rb-inotify", require: false
end

group :production do
  # gem 'logglier', '~> 0.2.11'                    # sending logs to loggly.com
  # gem 'lograge',  '~> 0.3.4'                     # abbreviated rails logs
  gem 'exception_notification', '~> 4.1.1'       # notification of exceptions via email
end

# gem 'elbas', github: 'lserman/capistrano-elbas'

Debian instance info:

Static hostname: debian-1cpu-1gb-us-chi1
         Icon name: computer-vm
           Chassis: vm
        Machine ID: 0072a07a9c1349898ba2e35eb78cd8d2
           Boot ID: bfb5d8b9d8cf42d4b766b5089a926016
    Virtualization: kvm
  Operating System: Debian GNU/Linux 10 (buster)
            Kernel: Linux 4.19.0-9-amd64
      Architecture: x86-64

OpenSSL version:

OpenSSL 1.1.1d  10 Sep 2019

Dokku MYSQL plugin MYSQL version:

5.7.28

I'm thinking I need to figure out how to build the mysql2 gem with the correct version of openSSL on the debian instance but I'm at a bit of a loss on how I would do that. The mysql2 gem install blew up locally until I installed it with the optional arguments mentioned at the top. The mysql2 gem version installs fine on the debian instance. Any help would be appreciated.