Committing changes I had to make to get puma working on production.

Gemfile

@@ -106,8 +106,6 @@ gem("jbuilder")
 # Use ActiveModel has_secure_password
 gem("bcrypt", "~> 3.1.7")
 
-# Use unicorn as the app server
-# gem("unicorn")
 # Use puma as the app server
 gem("puma")
 

config/environments/production.rb

@@ -134,7 +134,7 @@
   # personally identifiable information (PII). If you want to log everything,
   # set the level to "debug".
   # config.log_level = ENV.fetch("RAILS_LOG_LEVEL", "info")
-  config.log_level = :debug
+  config.log_level = :info
 
   # Disable automatic flushing of the log to improve performance.
   # config.autoflush_log = false

config/etc/nginx.conf

@@ -148,17 +148,14 @@ http {
       proxy_set_header X-Forwarded-Proto https;
       proxy_set_header Host $http_host;
 
-      # enable this if you forward HTTPS traffic to unicorn
-      # proxy_set_header X-Forwarded-Proto $scheme;
-
       # we don't want nginx trying to mess with redirects
       proxy_redirect off;
 
       # enforce limit on rate of requests for all requests processed by rails
       limit_req zone=one burst=10;
 
       # this is where unicorn is listening
-      # proxy_pass http://unicorn;
+      proxy_pass http://puma;
 
       # track progress of all POST requests at this location, MUST BE LAST!
       # track_uploads upload 10s;

config/etc/puma.service

@@ -10,23 +10,24 @@ After=network.target
 # monitoring, as of Puma 5.1 or later.
 # On earlier versions of Puma or JRuby, change this to `Type=simple` and remove
 # the `WatchdogSec` line.
-Type=notify
+# Type=notify
+Type=simple
 
 # If your Puma process locks up, systemd's watchdog will restart it within seconds.
-WatchdogSec=10
+# WatchdogSec=10
 
 # Preferably configure a non-privileged user
-# User=
+User=mo
 
 # The path to your application code root directory.
 # Also replace the "<YOUR_APP_PATH>" placeholders below with this path.
 # Example /home/username/myapp
 WorkingDirectory=/var/web/mo
 
-PIDFile=/var/web/mo/puma.pid
+PIDFile=/var/web/mo/tmp/puma.pid
 Environment=RAILS_ENV=production
 # Helpful for debugging socket activation, etc.
-# Environment=PUMA_DEBUG=1
+Environment=PUMA_DEBUG=1
 
 # SystemD will not run puma even if it is in your path. You must specify
 # an absolute URL to puma. For example /usr/local/bin/puma
@@ -40,9 +41,7 @@ Environment=RAILS_ENV=production
 # Variant: Specify directives inline.
 # ExecStart=/<FULLPATH>/puma -b tcp://0.0.0.0:9292 -b ssl://0.0.0.0:9293?key=key.pem&cert=cert.pem
 
-# Working example for Rails from the web:
-ExecStart=/var/web/mo/bin/bundle exec puma -e production -C ./config/puma.rb config.ru
-# For switching to Puma with a rolling restart, replace <USR1> with a different user than the one running Unicorn.
+ExecStart=/var/web/mo/bin/puma
 ExecReload=/bin/kill -s $MAINPID
 ExecStop=/bin/kill -s QUIT $MAINPID
 

config/puma.rb

@@ -1,23 +1,21 @@
 # frozen_string_literal: true
 
-workers Integer(ENV["WEB_CONCURRENCY"] || 3)
-threads_count = Integer(ENV["MAX_THREADS"] || 1)
-threads threads_count, threads_count
+workers 3
+threads 1, 1
 
-# preload_app!
-prune_bundler
+app_path = "/var/web/mushroom-observer"
+rails_env = "production"
 
-rackup              DefaultRackup if defined?(DefaultRackup)
-port                ENV["PORT"]     || 3000
-environment         ENV["RAILS_ENV"] || "production"
-
-# directory           "/var/web/mo"
-# redirect_stderr     "/var/web/mo/log/puma.stderr.log"
-# redirect_stdout     "/var/web/mo/log/puma.stdout.log"
-# bind                "/var/web/mo/tmp/sockets/puma.sock"
-# pidfile             "/var/web/mo/tmp/pids/puma.pid"
-
-# on_worker_boot do
-#   ActiveRecord::Base.establish_connection
-# end
+environment         rails_env
+bind                "unix://#{app_path}/tmp/sockets/puma.sock"
+stdout_redirect     "#{app_path}/log/puma.stdout.log",
+                    "#{app_path}/log/puma.stderr.log", true
+pidfile             "#{app_path}/tmp/pids/puma.pid"
+state_path          "#{app_path}/tmp/pids/puma.state"
+activate_control_app
 
+on_worker_boot do
+  require "active_record"
+  ActiveRecord::Base.connection.disconnect! rescue ActiveRecord::ConnectionNotEstablished
+  ActiveRecord::Base.establish_connection(YAML.load_file("#{app_dir}/config/database.yml")[rails_env])
+end

script/deploy.sh

@@ -29,7 +29,7 @@ echo Installing bundle... && bundle install && \
 echo Checking for migrations... && rake db:migrate && \
 echo Updating translations... && rake lang:update && \
 echo Precompiling assets... && rake assets:precompile && \
-# echo Reloading unicorn... && /etc/init.d/unicorn reload && \
+echo Reloading puma... && sudo system puma restart && \
 echo Tagging repo with $tag... && git tag $tag && \
 echo Pushing new tag... && git push --tags && \
 echo SUCCESS\!