Use Ruby 3.1.5 for Rails 6.1-7.2, Ruby 3.4 for Rails 8.0-8.1

Updated Docker configuration to use specific Ruby versions for each Rails version:
- Rails 5.1-6.0: Ruby 2.7 with bundler 2.4.22
- Rails 6.1-7.2: Ruby 3.1.5 with bundler 2.4.14
- Rails 8.0-8.1: Ruby 3.4 with bundler 2.4.14

Rails 8.0+ requires Ruby >= 3.2.0, so we use Ruby 3.4 for these versions.
All tests pass successfully for all 9 Rails versions.

Changes:
- Created Dockerfile.ruby3.1 for Ruby 3.1.5
- Created Dockerfile.ruby3.4 for Ruby 3.4
- Updated docker-compose.yml to use appropriate Ruby versions
- Added separate bundle cache volumes for each Ruby version

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: takaokouji

Dockerfile.ruby3.1

@@ -15,8 +15,10 @@ WORKDIR /app
 COPY Gemfile jsonapi-resources.gemspec ./
 COPY lib/jsonapi/resources/version.rb ./lib/jsonapi/resources/
 
-# Install bundler
-RUN gem install bundler
+# Install specific bundler version for compatibility
+RUN gem install bundler -v 2.4.14 --no-document && \
+    gem install bundler -v 2.4.14 --install-dir /usr/local/bundle --no-document && \
+    bundle --version
 
 # Note: bundle install will happen at runtime with specific RAILS_VERSION
 # This allows testing multiple Rails versions without rebuilding the image

Dockerfile.ruby3.4

@@ -0,0 +1,24 @@
+# Dockerfile for testing jsonapi-resources with Rails 8.0-8.1 (Ruby 3.4)
+
+FROM ruby:3.4
+
+# Install dependencies
+RUN apt-get update -qq && \
+    apt-get install -y build-essential libpq-dev nodejs && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
+
+# Set working directory
+WORKDIR /app
+
+# Copy Gemfile and gemspec
+COPY Gemfile jsonapi-resources.gemspec ./
+COPY lib/jsonapi/resources/version.rb ./lib/jsonapi/resources/
+
+# Install specific bundler version for compatibility
+RUN gem install bundler -v 2.4.14 --no-document && \
+    gem install bundler -v 2.4.14 --install-dir /usr/local/bundle --no-document && \
+    bundle --version
+
+# Note: bundle install will happen at runtime with specific RAILS_VERSION
+# This allows testing multiple Rails versions without rebuilding the image

docker-compose.yml

@@ -6,7 +6,7 @@ services:
       dockerfile: Dockerfile.ruby3.1
     volumes:
       - .:/app
-      - bundle-cache:/usr/local/bundle
+      - bundle-cache-ruby31:/usr/local/bundle
     working_dir: /app
     stdin_open: true
     tty: true
@@ -23,6 +23,18 @@ services:
     stdin_open: true
     tty: true
 
+  # Base service definition for Ruby 3.4 (Rails 8.0-8.1)
+  test-base-ruby34: &test-base-ruby34
+    build:
+      context: .
+      dockerfile: Dockerfile.ruby3.4
+    volumes:
+      - .:/app
+      - bundle-cache-ruby34:/usr/local/bundle
+    working_dir: /app
+    stdin_open: true
+    tty: true
+
   # Rails 5.1.7
   rails-5.1:
     <<: *test-base-ruby27
@@ -53,47 +65,47 @@ services:
     container_name: jsonapi-rails-6.1
     environment:
       - RAILS_VERSION=6.1.7.10
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
   # Rails 7.0.10
   rails-7.0:
     <<: *test-base
     container_name: jsonapi-rails-7.0
     environment:
       - RAILS_VERSION=7.0.10
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
   # Rails 7.1.6
   rails-7.1:
     <<: *test-base
     container_name: jsonapi-rails-7.1
     environment:
       - RAILS_VERSION=7.1.6
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
   # Rails 7.2.3
   rails-7.2:
     <<: *test-base
     container_name: jsonapi-rails-7.2
     environment:
       - RAILS_VERSION=7.2.3
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
-  # Rails 8.0.4
+  # Rails 8.0.4 (Ruby 3.4 required)
   rails-8.0:
-    <<: *test-base
+    <<: *test-base-ruby34
     container_name: jsonapi-rails-8.0
     environment:
       - RAILS_VERSION=8.0.4
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
-  # Rails 8.1.2
+  # Rails 8.1.2 (Ruby 3.4 required)
   rails-8.1:
-    <<: *test-base
+    <<: *test-base-ruby34
     container_name: jsonapi-rails-8.1
     environment:
       - RAILS_VERSION=8.1.2
-    command: bash -c "rm -f Gemfile.lock && bundle install && bundle exec rake test"
+    command: bash -c "rm -f Gemfile.lock && /usr/local/bin/bundler _2.4.14_ install && /usr/local/bin/bundler _2.4.14_ exec rake test"
 
   # Interactive shell for debugging (defaults to Rails 8.1)
   shell:
@@ -104,5 +116,6 @@ services:
     command: /bin/bash
 
 volumes:
-  bundle-cache:
+  bundle-cache-ruby31:
   bundle-cache-ruby27:
+  bundle-cache-ruby34: