Setup next_rails to dual-boot Rails

With a workflow in GitHub Actions to detect potential issues with the
next Rails version. It's not possible to use CircleCI since we can't
filter PRs based on their branch name.

The module RailsVersion is to help with migrating code to a newer Rails
version.

.github/workflows/next_rails.yml

@@ -0,0 +1,44 @@
+name: Continuous integration for next Rails version
+
+# Run this workflow on the branch master and on PRs with the prefix next_rails- in their branch name
+on:
+  push:
+    branches:
+      - master
+      - 'next_rails-*'
+  pull_request:
+    branches:
+      - 'next_rails-*'
+
+jobs:
+  next_rails:
+    runs-on: ubuntu-20.04 # This is required, but we're running all steps in the container defined below
+    container:
+      image: registry.opensuse.org/obs/server/unstable/container/ci/containers/openbuildservice/frontend-base:latest
+      env:
+        NOKOGIRI_USE_SYSTEM_LIBRARIES: 1
+      options: --user frontend
+    services:
+      database:
+        image: registry.opensuse.org/obs/server/unstable/container/ci/containers/openbuildservice/mariadb:latest
+        # TODO: How to change the command of a service container?
+        # command: |
+        #   /bin/bash -c 'echo -e "[mysqld]\ndatadir = /dev/shm" > /etc/my.cnf.d/obs.cnf && cp -a /var/lib/mysql/* /dev/shm && /usr/lib/mysql/mysql-systemd-helper start'
+        options: --name db
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Install dependencies
+        uses: ruby/setup-ruby@v1
+      - name: Install dependencies from src/api/Gemfile.next
+        run: cd ./src/api && && next bundle install --jobs=4 --retry=3
+      - name: Init submodule
+        run: git submodule update --init --recursive --remote
+      - name: Wait for DB
+        run: mysqladmin ping -h db
+      - name: Create database with next Rails version
+        run: cd src/api; next bundle exec rake db:setup RAILS_ENV=test
+      - name: Run specs
+        run: cd src/api && next bundle exec rspec --format progress --format RspecJunitFormatter -o /home/frontend/rspec/rspec.db.xml
+      - name: Run minitest test suite
+        run: cd src/api && next bundle exec rake test:api:group1 test:api:group2

dist/obs-server.spec

@@ -468,6 +468,9 @@ rm -rf %{buildroot}%{__obs_api_prefix}/spec
 # only config for CI
 rm %{buildroot}%{__obs_api_prefix}/config/brakeman.ignore
 
+# Remove Gemfile.next and Gemfile.next.lock since they are only for testing the next Rails version in development and test environments
+rm %{buildroot}%{__obs_api_prefix}/Gemfile.next %{buildroot}%{__obs_api_prefix}/Gemfile.next.lock
+
 # fail when Makefiles created a directory
 if ! test -L %{buildroot}/usr/lib/obs/server/build; then
   echo "/usr/lib/obs/server/build is not a symlink!"

src/api/Gemfile

@@ -1,8 +1,18 @@
+# next? was generated with `next --init`
+# src/api/Gemfile.next.lock was generated with `next bundle install`
+def next?
+  File.basename(__FILE__) == 'Gemfile.next'
+end
+
 # Edit this Gemfile to bundle your application's dependencies.
 source 'https://rubygems.org'
 
-# We have a version constraint to tackle Rails updates whenever we have time
-gem 'rails', '~> 6.0'
+# Start the Rails application using src/api/Gemfile.next with `next rails s`
+if next?
+  gem 'rails', '~> 6.1'
+else
+  gem 'rails', '~> 6.0'
+end
 
 # as our database
 gem 'mysql2'
@@ -173,6 +183,8 @@ end
 group :development do
   # add a comment summarizing the current schema
   gem 'annotate'
+  # toolkit to upgrade your Rails application
+  gem 'next_rails'
 end
 
 # Gems used only for assets and not required in production environments by default.

src/api/Gemfile.lock

@@ -115,6 +115,7 @@ GEM
     codecov (0.5.1)
       simplecov (>= 0.15, < 0.22)
     coderay (1.1.3)
+    colorize (0.8.1)
     concurrent-ruby (1.1.8)
     coveralls (0.8.23)
       json (>= 1.8, < 3)
@@ -244,6 +245,8 @@ GEM
       ruby-progressbar
     mocha (1.12.0)
     mysql2 (0.5.3)
+    next_rails (1.0.4)
+      colorize (>= 0.8.1)
     nio4r (2.5.7)
     nokogiri (1.11.3)
       mini_portile2 (~> 2.5.0)
@@ -493,6 +496,7 @@ DEPENDENCIES
   minitest-reporters
   mocha
   mysql2
+  next_rails
   nokogiri
   pry
   pry-byebug

src/api/Gemfile.next

@@ -0,0 +1 @@
+Gemfile