ci(docker): add docker files

.dockerignore

@@ -0,0 +1,47 @@
+# This file excludes paths from the Docker build context.
+#
+# By default, Docker's build context includes all files (and folders) in the
+# current directory. Even if a file isn't copied into the container it is still sent to
+# the Docker daemon.
+#
+# There are multiple reasons to exclude files from the build context:
+#
+# 1. Prevent nested folders from being copied into the container (ex: exclude
+#    /assets/node_modules when copying /assets)
+# 2. Reduce the size of the build context and improve build time (ex. /build, /deps, /doc)
+# 3. Avoid sending files containing sensitive information
+#
+# More information on using .dockerignore is available here:
+# https://docs.docker.com/engine/reference/builder/#dockerignore-file
+
+.dockerignore
+
+# Ignore git, but keep git HEAD and refs to access current commit hash if needed:
+#
+# $ cat .git/HEAD | awk '{print ".git/"$2}' | xargs cat
+# d0b8727759e1e0e7aa3d41707d12376e373d5ecc
+.git
+!.git/HEAD
+!.git/refs
+
+# Common development/test artifacts
+/cover/
+/doc/
+/test/
+/tmp/
+.elixir_ls
+.lexical
+.gitea
+
+# Mix artifacts
+/_build/
+/deps/
+*.ez
+
+# Generated on crash by the VM
+erl_crash.dump
+
+# Static artifacts - These should be fetched and built inside the Docker image
+/assets/node_modules/
+/priv/static/assets/
+/priv/static/cache_manifest.json

.gitignore

@@ -28,6 +28,11 @@ exmr-*.tar
 # Ignore assets that are produced by build tools.
 /priv/static/assets/
 
+# Ignore editor files.
+/.elixir_ls/
+/.lexical/
+/.vscode
+
 # Ignore digested assets cache.
 /priv/static/cache_manifest.json
 
@@ -35,3 +40,5 @@ exmr-*.tar
 npm-debug.log
 /assets/node_modules/
 
+# ignore release artifacts
+/rel/

Dockerfile

@@ -0,0 +1,97 @@
+# Find eligible builder and runner images on Docker Hub. We use Ubuntu/Debian
+# instead of Alpine to avoid DNS resolution issues in production.
+#
+# https://hub.docker.com/r/hexpm/elixir/tags?page=1&name=ubuntu
+# https://hub.docker.com/_/ubuntu?tab=tags
+#
+# This file is based on these images:
+#
+#   - https://hub.docker.com/r/hexpm/elixir/tags - for the build image
+#   - https://hub.docker.com/_/debian?tab=tags&page=1&name=bullseye-20241111-slim - for the release image
+#   - https://pkgs.org/ - resource for finding needed packages
+#   - Ex: hexpm/elixir:1.17.3-erlang-25.3.2.15-debian-bullseye-20241111-slim
+#
+ARG ELIXIR_VERSION=1.17.3
+ARG OTP_VERSION=25.3.2.15
+ARG DEBIAN_VERSION=bullseye-20241111-slim
+
+ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
+ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"
+
+FROM ${BUILDER_IMAGE} as builder
+
+# install build dependencies
+RUN apt-get update -y && apt-get install -y build-essential git \
+    && apt-get clean && rm -f /var/lib/apt/lists/*_*
+
+# prepare build dir
+WORKDIR /app
+
+# install hex + rebar
+RUN mix local.hex --force && \
+    mix local.rebar --force
+
+# set build ENV
+ENV MIX_ENV="prod"
+
+# install mix dependencies
+COPY mix.exs mix.lock ./
+RUN mix deps.get --only $MIX_ENV
+RUN mkdir config
+
+# copy compile-time config files before we compile dependencies
+# to ensure any relevant config change will trigger the dependencies
+# to be re-compiled.
+COPY config/config.exs config/${MIX_ENV}.exs config/
+RUN mix deps.compile
+
+COPY priv priv
+
+COPY lib lib
+
+COPY assets assets
+
+# compile assets
+RUN mix assets.deploy
+
+# Compile the release
+RUN mix compile
+
+# Changes to config/runtime.exs don't require recompiling the code
+COPY config/runtime.exs config/
+
+COPY rel rel
+RUN mix release
+
+# start a new build stage so that the final image will only contain
+# the compiled release and other runtime necessities
+FROM ${RUNNER_IMAGE}
+
+RUN apt-get update -y && \
+  apt-get install -y libstdc++6 openssl libncurses5 locales ca-certificates \
+  && apt-get clean && rm -f /var/lib/apt/lists/*_*
+
+# Set the locale
+RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && locale-gen
+
+ENV LANG en_US.UTF-8
+ENV LANGUAGE en_US:en
+ENV LC_ALL en_US.UTF-8
+
+WORKDIR "/app"
+RUN chown nobody /app
+
+# set runner ENV
+ENV MIX_ENV="prod"
+
+# Only copy the final release from the build stage
+COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/exmr ./
+
+USER nobody
+
+# If using an environment that doesn't automatically reap zombie processes, it is
+# advised to add an init process such as tini via `apt-get install`
+# above and adding an entrypoint. See https://github.com/krallin/tini for details
+# ENTRYPOINT ["/tini", "--"]
+
+CMD ["/app/bin/server"]

docker-compose.yml

@@ -0,0 +1,23 @@
+services:
+  app:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    ports:
+      - "4000:4000"
+    environment:
+      - DATABASE_URL=${DATABASE_URL}
+      - SECRET_KEY_BASE=${SECRET_KEY_BASE}
+    depends_on: db
+
+  db:
+    image: postgres:16-alpine
+    environment:
+      - POSTGRES_USER=${POSTGRES_USER}
+      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
+      - POSTGRES_DB=${POSTGRES_DB}
+    volumes:
+      - db_data:/var/lib/postgresql/data
+
+volumes:
+  db_data:

lib/exmr/release.ex

@@ -0,0 +1,28 @@
+defmodule Exmr.Release do
+  @moduledoc """
+  Used for executing DB release tasks when run in production without Mix
+  installed.
+  """
+  @app :exmr
+
+  def migrate do
+    load_app()
+
+    for repo <- repos() do
+      {:ok, _, _} = Ecto.Migrator.with_repo(repo, &Ecto.Migrator.run(&1, :up, all: true))
+    end
+  end
+
+  def rollback(repo, version) do
+    load_app()
+    {:ok, _, _} = Ecto.Migrator.with_repo(repo, &Ecto.Migrator.run(&1, :down, to: version))
+  end
+
+  defp repos do
+    Application.fetch_env!(@app, :ecto_repos)
+  end
+
+  defp load_app do
+    Application.load(@app)
+  end
+end