Lession 220: Ruby without Rails implementation

lessons/220/deploy/ruby-app/0-config.yaml

@@ -0,0 +1,23 @@
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: ruby-app
+  namespace: default
+data:
+  database.yml: |
+    default: &default
+      adapter: postgresql
+      encoding: unicode
+      timeout: 5000
+      host: postgresql.antonputra.pvt
+      database: mydb
+      pool: 50
+      username: rails
+      password: devops123
+
+    development:
+      !!merge <<: *default
+
+    production:
+      !!merge <<: *default

lessons/220/deploy/ruby-app/1-deployment.yaml

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+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: ruby-app
+  namespace: default
+spec:
+  replicas: 2
+  strategy:
+    type: Recreate
+  selector:
+    matchLabels:
+      app: ruby-app
+  template:
+    metadata:
+      labels:
+        app: ruby-app
+    spec:
+      terminationGracePeriodSeconds: 0
+      initContainers:
+      - name: migration
+        image: aputra/ruby-app-220:v5
+        command: ['sh', '-c', "/rails/bin/rake db:migrate"]
+        volumeMounts:
+        - name: config
+          mountPath: /rails/db/config.yml
+          subPath: config.yml
+      containers:
+      - name: ruby-app
+        image: aputra/ruby-app-220:v5
+        ports:
+        - name: http
+          containerPort: 8080
+        - name: WORKERS_NUM
+          value: "2" # 0 for single-mode
+        - name: RAILS_MAX_THREADS
+          value: "2"
+        resources:
+          requests:
+            memory: 512Mi
+            cpu: 750m
+          limits:
+            memory: 512Mi
+            cpu: 1000m
+        readinessProbe:
+          httpGet:
+            path: /up
+            port: http
+        livenessProbe:
+          httpGet:
+            path: /up
+            port: http
+        volumeMounts:
+        - name: config
+          mountPath: /rails/db/config.yml
+          subPath: config.yml
+      volumes:
+      - name: config
+        configMap:
+          name: ruby-app
+      tolerations:
+      - effect: NoSchedule
+        operator: Exists
+      affinity:
+        podAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+          - labelSelector:
+              matchExpressions:
+              - key: app
+                operator: In
+                values:
+                - ruby-app
+            topologyKey: "kubernetes.io/hostname"
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+            - matchExpressions:
+              - key: node
+                operator: In
+                values:
+                - general
+            - matchExpressions:
+              - key: kubernetes.io/arch
+                operator: In
+                values:
+                - amd64

lessons/220/deploy/ruby-app/2-service.yaml

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+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: ruby-app
+  namespace: default
+spec:
+  ports:
+  - name: http
+    port: 8080
+    targetPort: http
+  selector:
+    app: ruby-app
+  type: ClusterIP

lessons/220/deploy/ruby-app/3-pod-monitor.yaml

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+---
+apiVersion: monitoring.coreos.com/v1
+kind: PodMonitor
+metadata:
+  name: ruby-app
+  namespace: monitoring
+  labels:
+    prometheus: main
+spec:
+  namespaceSelector:
+    matchNames:
+    - default
+  selector:
+    matchLabels:
+      app: ruby-app
+  podMetricsEndpoints:
+  - port: http

lessons/220/deploy/ruby-app/4-client-pod-monitor.yaml

@@ -0,0 +1,17 @@
+---
+apiVersion: monitoring.coreos.com/v1
+kind: PodMonitor
+metadata:
+  name: rails-client
+  namespace: monitoring
+  labels:
+    prometheus: main
+spec:
+  namespaceSelector:
+    matchNames:
+    - default
+  selector:
+    matchLabels:
+      app: rails-client
+  podMetricsEndpoints:
+  - port: metrics

lessons/220/ruby-app/.dockerignore

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+# See https://docs.docker.com/engine/reference/builder/#dockerignore-file for more about ignoring files.
+
+# Ignore git directory.
+/.git/
+/.gitignore
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all environment files (except templates).
+/.env*
+!/.env*.erb
+
+# Ignore all default key files.
+/config/master.key
+/config/credentials/*.key
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/.keep
+
+# Ignore storage (uploaded files in development and any SQLite databases).
+/storage/*
+!/storage/.keep
+/tmp/storage/*
+!/tmp/storage/.keep
+
+# Ignore CI service files.
+/.github
+
+# Ignore development files
+/.devcontainer
+
+# Ignore Docker-related files
+/.dockerignore
+/Dockerfile*

lessons/220/ruby-app/.gitattributes

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+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
+config/credentials/*.yml.enc diff=rails_credentials
+config/credentials.yml.enc diff=rails_credentials

lessons/220/ruby-app/.gitignore

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+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# Temporary files generated by your text editor or operating system
+# belong in git's global ignore instead:
+# `$XDG_CONFIG_HOME/git/ignore` or `~/.config/git/ignore`
+
+# Ignore bundler config.
+/.bundle
+/.idea
+
+# Ignore all environment files (except templates).
+/.env*
+!/.env*.erb
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+# Ignore storage (uploaded files in development and any SQLite databases).
+/storage/*
+!/storage/.keep
+/tmp/storage/*
+!/tmp/storage/
+!/tmp/storage/.keep
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key

lessons/220/ruby-app/.ruby-version

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+ruby-3.3.5

lessons/220/ruby-app/Dockerfile

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+# syntax = docker/dockerfile:1
+
+# This Dockerfile is designed for production, not development. Use with Kamal or build'n'run by hand:
+# docker build -t ruby-app .
+# docker run -d -p 8080:8080 --name ruby-app ruby-app
+
+# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
+ARG RUBY_VERSION=3.3.5
+FROM docker.io/library/ruby:$RUBY_VERSION-slim AS base
+
+# Rails app lives here
+WORKDIR /rails
+
+# Install base packages
+RUN apt-get update -qq && \
+    apt-get install --no-install-recommends -y curl libjemalloc2 libvips sqlite3 libpq-dev && \
+    rm -rf /var/lib/apt/lists /var/cache/apt/archives
+
+# Set production environment
+ENV RAKE_ENV="production" \
+    BUNDLE_DEPLOYMENT="1" \
+    BUNDLE_PATH="/usr/local/bundle" \
+    BUNDLE_WITHOUT="development"
+
+# Throw-away build stage to reduce size of final image
+FROM base AS build
+
+# Install packages needed to build gems
+RUN apt-get update -qq && \
+    apt-get install --no-install-recommends -y build-essential git pkg-config && \
+    rm -rf /var/lib/apt/lists /var/cache/apt/archives
+
+# Install application gems
+COPY Gemfile Gemfile.lock ./
+RUN bundle install && \
+    rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git
+
+# Copy application code
+COPY . .
+
+# Final stage for app image
+FROM base
+
+# Copy built artifacts: gems, application
+COPY --from=build "${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 tmp
+USER 1000:1000
+
+# Entrypoint prepares the database.
+ENTRYPOINT ["/rails/bin/docker-entrypoint"]
+
+# Start the server by default, this can be overwritten at runtime
+EXPOSE 8080
+CMD ["bin/iodine", "-p 8080", "config.ru"]

lessons/220/ruby-app/Gemfile

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+# frozen_string_literal: true
+
+source 'https://rubygems.org'
+
+gem 'connection_pool'
+gem 'pg'
+gem 'rake'
+gem 'standalone_migrations', require: false
+
+gem 'oj'
+gem 'prometheus-client'
+gem 'rack'
+gem 'rage-iodine'