Add new recipe how to deploy an Inertia Rails app with Kamal and SSR support

docs/.vitepress/config.mts

@@ -135,6 +135,12 @@ export default defineConfig({
                 { text: 'shadcn/ui', link: '/cookbook/integrating-shadcn-ui' },
               ],
             },
+            {
+              text: 'Deployment',
+              items: [
+                { text: 'Deploy with Kamal', link: '/cookbook/deploy-with-kamal' },
+              ],
+            },
           ],
         },
       ],

docs/cookbook/deploy-with-kamal.md

@@ -0,0 +1,233 @@
+# Deploy with `Kamal`
+
+Rails 8 will ship with [Kamal](https://kamal-deploy.org/) preconfigured as the default deployment tool.
+If your application does not require [SSR](/guide/server-side-rendering.md), you simply just need to
+[update your asset_path](#update-asset-path-inconfig-deploy-yml), and deployment should work seamlessly.
+
+However, if you plan to configure your Inertia Rails application with [SSR](/guide/server-side-rendering.md) enabled,
+a few additional tweaks may be required. This guide will walk you through the steps to quickly configure
+[Kamal](https://kamal-deploy.org/) for deploying your next Inertia Rails application with
+[SSR](/guide/server-side-rendering.md) support.
+
+> Note: This guide is based on Rails 8.0 and Kamal 2.3.0 at the time of writing.
+
+
+## Update your Dockerfile
+
+It is crucial to ensure that the **_Install JavaScript dependencies_** step is executed in the **_base_** image. This
+guarantees that the Node.js runtime is available for both the **_build_** stage and the **_runtime_** stage.
+
+```dockerfile
+# syntax=docker/dockerfile:1
+# check=error=true
+
+# This Dockerfile is designed for production, not development. Use with Kamal or build'n'run by hand:
+# docker build -t fresh_rails .
+# docker run -d -p 80:80 -e RAILS_MASTER_KEY=<value from config/master.key> --name fresh_rails fresh_rails
+
+# For a containerized dev environment, see Dev Containers: https://guides.rubyonrails.org/getting_started_with_devcontainer.html
+
+# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
+ARG RUBY_VERSION=3.3.6
+FROM docker.io/library/ruby:$RUBY_VERSION-slim AS base
+
+# Rails app lives here
+WORKDIR /rails
+
+# Install base packages
+RUN apt-get update -qq && \
+    apt-get install --no-install-recommends -y curl libjemalloc2 libvips sqlite3 && \
+    rm -rf /var/lib/apt/lists /var/cache/apt/archives
+
+# Install JavaScript dependencies // [!code ++]
+ARG NODE_VERSION=22.11.0 // [!code ++]
+ARG YARN_VERSION=1.22.22 // [!code ++]
+ENV PATH=/usr/local/node/bin:$PATH // [!code ++]
+RUN curl -sL https://github.com/nodenv/node-build/archive/master.tar.gz | tar xz -C /tmp/ && \ // [!code ++]
+    /tmp/node-build-master/bin/node-build "${NODE_VERSION}" /usr/local/node && \ // [!code ++]
+    npm install -g yarn@$YARN_VERSION && \ // [!code ++]
+    rm -rf /tmp/node-build-master // [!code ++]
+
+# Set production environment
+ENV RAILS_ENV="production" \
+    BUNDLE_DEPLOYMENT="1" \
+    BUNDLE_PATH="/usr/local/bundle" \
+    BUNDLE_WITHOUT="development"
+
+# Throw-away build stage to reduce size of final image
+FROM base AS build
+
+# Install packages needed to build gems and node modules  // [!code ++]
+# Install packages needed to build gems  // [!code --]
+RUN apt-get update -qq && \
+    apt-get install --no-install-recommends -y build-essential git libpq-dev node-gyp pkg-config python-is-python3 && \ // [!code ++]
+    apt-get install --no-install-recommends -y build-essential git pkg-config && \ // [!code --]
+    rm -rf /var/lib/apt/lists /var/cache/apt/archives
+
+# Install application gems
+COPY .ruby-version Gemfile Gemfile.lock ./
+RUN bundle install && \
+    rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
+    bundle exec bootsnap precompile --gemfile
+
+# Install node modules // [!code ++]
+COPY package.json yarn.lock ./ // [!code ++]
+RUN yarn install --frozen-lockfile // [!code ++]
+
+# Copy application code
+COPY . .
+
+# Precompile bootsnap code for faster boot times
+RUN bundle exec bootsnap precompile app/ lib/
+
+# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
+RUN SECRET_KEY_BASE_DUMMY=1 ./bin/rails assets:precompile
+
+RUN rm -rf node_modules // [!code ++]
+
+
+# Final stage for app image
+FROM base
+
+# Copy built artifacts: gems, application
+COPY --from=build "${BUNDLE_PATH}" "${BUNDLE_PATH}"
+COPY --from=build /rails /rails
+
+# Run and own only the runtime files as a non-root user for security
+RUN groupadd --system --gid 1000 rails && \
+    useradd rails --uid 1000 --gid 1000 --create-home --shell /bin/bash && \
+    chown -R rails:rails db log storage tmp
+USER 1000:1000
+
+# Entrypoint prepares the database.
+ENTRYPOINT ["/rails/bin/docker-entrypoint"]
+
+# Start server via Thruster by default, this can be overwritten at runtime
+EXPOSE 80
+CMD ["./bin/thrust", "./bin/rails", "server"]
+```
+
+
+## Setup server role to run SSR server in `config/deploy.yml`
+
+The Node-based Inertia SSR server is used to pre-render pages on the server before sending them to the client.
+The `vite_ssr` role ensures that the SSR server runs separately from the main Rails app server.
+
+```yml
+# Deploy to these servers.
+servers:
+  web:
+    - 192.168.0.1
+  vite_ssr: // [!code ++]
+    hosts: // [!code ++]
+      - 192.168.0.1 // [!code ++]
+    cmd: bundle exec vite ssr // [!code ++]
+    options: // [!code ++]
+      network-alias: vite_ssr // [!code ++]
+  # job:
+  #   hosts:
+  #     - 192.168.0.1
+  #   cmd: bin/jobs
+```
+
+
+## Specify the Vite server in `config/deploy.yml`
+
+The Rails app needs to know where to send SSR requests. Add the `VITE_RUBY_HOST` environment variable
+to ensure your Rails application can connect to the correct SSR server. The value **_VITE_RUBY_HOST: "vite_ssr"_**
+must match the **_network-alias_** defined in the `vite_ssr` role above.
+
+```yml
+# Inject ENV variables into containers (secrets come from .kamal/secrets).
+env:
+  secret:
+    - RAILS_MASTER_KEY
+  clear:
+    # Run the Solid Queue Supervisor inside the web server's Puma process to do jobs.
+    # When you start using multiple servers, you should split out job processing to a dedicated machine.
+    SOLID_QUEUE_IN_PUMA: true
+
+    VITE_RUBY_HOST: "vite_ssr" // [!code ++]
+
+    # Set number of processes dedicated to Solid Queue (default: 1)
+    # JOB_CONCURRENCY: 3
+
+    # Set number of cores available to the application on each server (default: 1).
+    # WEB_CONCURRENCY: 2
+
+    # Match this to any external database server to configure Active Record correctly
+    # Use inertia_rails_svelte5_ssr-db for a db accessory server on same machine via local kamal docker network.
+    # DB_HOST: 192.168.0.2
+
+    # Log everything from Rails
+    # RAILS_LOG_LEVEL: debug
+
+```
+
+
+## Update asset_path in`config/deploy.yml`
+
+Update the asset_path to `/rails/public/vite` if you haven't.
+
+```yml
+# Bridge fingerprinted assets, like JS and CSS, between versions to avoid
+# hitting 404 on in-flight requests. Combines all files from new and old
+# version inside the asset_path.
+asset_path: /rails/public/assets // [!code --]
+asset_path: /rails/public/vite // [!code ++]
+```
+
+
+## Ensure that your `vite.config.ts` is configured to support SSR
+
+Configure Vite with an `ssr` block in your `vite.config.ts` file to ensures all dependencies are bundled for SSR.
+
+```js
+import { svelte } from '@sveltejs/vite-plugin-svelte'
+import { defineConfig } from 'vite'
+import ViteRails from "vite-plugin-rails"
+
+export default defineConfig({
+    ssr: {// [!code ++]
+        noExternal: true,// [!code ++]
+    },// [!code ++]
+    plugins: [
+        svelte(),
+        ViteRails({
+            envVars: { RAILS_ENV: "development" },
+            envOptions: { defineOn: "import.meta.env" },
+            fullReload: {
+                additionalPaths: [],
+            },
+        }),
+    ],
+})
+```
+
+## Configure SSR URL in the Inertia's Rails adapter
+
+To enable Server-Side Rendering (SSR) in your Inertia Rails application, you need to specify
+the correct SSR server URL in the adapter. By default, the adapter points to `http://localhost:13714`,
+but this must align with the **_VITE_RUBY_HOST_** value defined in your `deploy.yml` when we deploy it to production.
+
+Update the configuration in `config/initializers/inertia_rails.rb` to dynamically construct the
+SSR URL using Vite Ruby's protocol, host, and port settings:
+
+```ruby
+InertiaRails.configure do |config|
+  config.ssr_enabled = ViteRuby.config.ssr_build_enabled
+  config.ssr_url = "#{ViteRuby.config.protocol}://#{ViteRuby.config.host}:13714" # [!code ++]
+  config.version = ViteRuby.digest
+end
+```
+
+
+## Deploy and enjoy 🎉
+
+Once everything is set up, you can deploy your application by running:
+
+* `kamal setup` (if you haven’t provisioned the server yet).
+* `kamal deploy` (to deploy your application).
+
+In just a few minutes, your application will be live and ready, complete with SSR support! 🎉
+Good luck, and happy deploying! 🚀