Add Puma as direct dependency

This commit adds `Puma` as a direct dependency to the Gemfile. Puma was previously installed indirectly through the dependency on `govuk_test` as part of the `dev` and `test` groups; given that we want to run Puma in production, we should instead make it a direct dependency.

Co-authored-by: Chris Banks <chris.banks@digital.cabinet-office.gov.uk>

Dockerfile

@@ -1,7 +1,6 @@
 ARG base_image=ruby:2.7.2
 FROM ${base_image}
 RUN apt-get update -qq && apt-get upgrade -y && apt-get install -y build-essential && apt-get clean
-RUN gem install foreman
 
 ENV GOVUK_APP_NAME content-store
 ENV GOVUK_CONTENT_SCHEMAS_PATH /govuk-content-schemas
@@ -17,4 +16,4 @@ ADD Gemfile* $APP_HOME/
 RUN bundle install
 ADD . $APP_HOME
 
-CMD foreman run web
+CMD bundle exec puma

Gemfile

@@ -9,6 +9,7 @@ gem "govuk-content-schema-test-helpers"
 gem "mongo"
 gem "mongoid"
 gem "plek"
+gem "puma"
 gem "rack-cache"
 gem "uuidtools"
 gem "whenever", require: false

Gemfile.lock

@@ -433,6 +433,7 @@ DEPENDENCIES
   pact
   plek
   pry-byebug
+  puma
   rack-cache
   rails (= 6.1.4.1)
   rspec-rails

config/puma.rb

@@ -21,9 +21,6 @@
 #
 environment ENV.fetch("RAILS_ENV") { "development" }
 
-# Specifies the `pidfile` that Puma will use.
-pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
-
 # Specifies the number of `workers` to boot in clustered mode.
 # Workers are forked web server processes. If using threads and workers together
 # the concurrency of the application would be max `threads` * `workers`.