Use Alpine Linux to built a smaller Docker image for Fab Manager

.dockerignore

@@ -5,12 +5,16 @@ vendor/cache
 config/database.yml
 config/application.yml
 
-# Ignore the default SQLite database.
+# Ignore database files.
 db/*.sqlite3
 db/*.sqlite3-journal
+postgresql
+elasticsearch
+redis
 
 # Ignore all logfiles and tempfiles.
 log
+*.log
 tmp
 
 public/uploads
@@ -24,10 +28,17 @@ invoices
 
 .DS_Store
 
+# Development files
 .vagrant
 Vagrantfile
-
+provision
 .git*
-
 Dockerfile
 docker-compose*
+
+# Docs
+*.md
+doc
+
+# Modules
+node_modules

Dockerfile

@@ -1,40 +1,52 @@
-FROM ruby:2.3
+FROM ruby:2.3.8-alpine
 MAINTAINER peng@sleede.com
 
-# First we need to be able to fetch from https repositories
-RUN apt-get update && \
-    apt-get install -y apt-transport-https \
-      ca-certificates apt-utils
-
-
-# Add sources for external tools to APT
-RUN curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - && \
-    curl -sSL https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add - && \
-    echo "deb https://dl.yarnpkg.com/debian/ stable main" > /etc/apt/sources.list.d/yarn.list && \
-    echo "deb https://deb.nodesource.com/node_10.x jessie main" > /etc/apt/sources.list.d/nodesource.list && \
-    echo "deb-src https://deb.nodesource.com/node_10.x jessie main" >> /etc/apt/sources.list.d/nodesource.list
-
-# Install apt based dependencies required to run Rails as
-# well as RubyGems. As the Ruby image itself is based on a
-# Debian image, we use apt-get to install those.
-RUN apt-get update && \
-    apt-get install -y \
+# Install upgrade system packages
+RUN apk update && apk upgrade && \
+# Install runtime apk dependencies
+    apk add --update curl \
       nodejs \
+      yarn \
+      imagemagick \
       supervisor \
-      yarn
+      tzdata \
+      libc-dev \
+      ruby-dev \
+      zlib-dev \
+      xz-dev \
+      postgresql-dev \
+      libxml2-dev \
+      libxslt-dev \
+      libidn-dev && \
+# Install buildtime apk dependencies
+    apk add --update --no-cache --virtual .build-deps alpine-sdk \
+      build-base \
+      linux-headers \
+      git \
+      patch
 
-# throw errors if Gemfile has been modified since Gemfile.lock
+# Throw error if Gemfile has been modified since Gemfile.lock
 RUN bundle config --global frozen 1
 
-# Run Bundle in a cache efficient way
+# Install gems in a cache efficient way
 WORKDIR /tmp
 COPY Gemfile /tmp/
 COPY Gemfile.lock /tmp/
-RUN bundle install --binstubs
+RUN bundle install --binstubs --without development test doc
 
+# Install Javascript packages
+WORKDIR /usr/src/app
+COPY package.json /usr/src/app/package.json
+COPY yarn.lock /usr/src/app/yarn.lock
+RUN yarn install
 
-# Clean up APT when done.
-#RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+# Clean up build deps, cached packages and temp files
+RUN apk del .build-deps && \
+    yarn cache clean && \
+    rm -rf /tmp/* \
+           /var/tmp/* \
+           /var/cache/apk/* \
+           /usr/lib/ruby/gems/*/cache/*
 
 # Web app
 RUN mkdir -p /usr/src/app && \
@@ -48,15 +60,7 @@ RUN mkdir -p /usr/src/app && \
     mkdir -p /usr/src/app/tmp/sockets && \
     mkdir -p /usr/src/app/tmp/pids
 
-WORKDIR /usr/src/app
-
 COPY docker/database.yml /usr/src/app/config/database.yml
-COPY package.json /usr/src/app/package.json
-COPY yarn.lock /usr/src/app/yarn.lock
-
-# Run Yarn
-RUN yarn install
-
 COPY . /usr/src/app
 
 # Volumes
@@ -68,12 +72,10 @@ VOLUME /usr/src/app/public/assets
 VOLUME /usr/src/app/accounting
 VOLUME /var/log/supervisor
 
-# Expose port 3000 to the Docker host, so we can access it
-# from the outside.
+# Expose port 3000 to the Docker host, so we can access it from the outside
 EXPOSE 3000
 
-# The main command to run when the container starts. Also
-# tell the Rails dev server to bind to all interfaces by
-# default.
+# The main command to run when the container starts. Also tell the Rails server
+# to bind to all interfaces by default.
 COPY docker/supervisor.conf /etc/supervisor/conf.d/fablab.conf
-CMD ["/usr/bin/supervisord"]
+CMD ["/usr/bin/supervisord", "-c", "/etc/supervisor/conf.d/fablab.conf"]