Reduce docker container size (#64)

.dockerignore

@@ -1,2 +1,7 @@
 ## DB data ##
+**/*.log
+**/target/
 db-data/
+Dockerfile
+.git
+.gitignore

CHANGELOG.md

@@ -5,6 +5,10 @@ file. This change log follows the conventions of
 [keepachangelog.com](http://keepachangelog.com/).
 
 ## [Unreleased]
+### Changed
+- Base docker images for production and testing moved to Linux
+  Alpine-based with Eclipse Temurin 17 JRE to reduce container size
+  ([#63](https://github.com/pilosus/dienstplan/issues/63))
 
 ## [0.2.12] - 2022-05-21
 

Dockerfile

@@ -1,20 +1,47 @@
 # syntax=docker/dockerfile:1
-# multi-stage docker file, separate build and run steps
+
+# Multi-stage docker file with separate build and run steps for image size optimisation
 # https://docs.docker.com/develop/develop-images/multistage-build/
+# Use Eclipse Temurin JDK/JRE as a vendor-agnostic, high-qulity solution
+# with permissive FLOSS license
+# https://whichjdk.com/#adoptium-eclipse-temurin
+
+###################
+### Build stage ###
+###################
+
+FROM clojure:temurin-17-lein-alpine@sha256:37968e7afb62937499c3773e9b713400da4abb358e6beb0ec9bae41a59715111 AS build
 
-# build step
-FROM clojure:openjdk-17-lein-bullseye
+# Create a working directory
 RUN mkdir -p /usr/src/app
-COPY project.clj /usr/src/app/
 WORKDIR /usr/src/app
+
+# Install deps as a separate step for layer caching
+COPY project.clj /usr/src/app/
 RUN lein deps
+
+# Compile uber-jar
 COPY . /usr/src/app
 RUN mv "$(lein uberjar | sed -n 's/^Created \(.*standalone\.jar\)/\1/p')" app.jar
 
-# run step
-FROM openjdk:17-slim-bullseye
+#################
+### Run stage ###
+#################
+
+FROM eclipse-temurin:17-jre-alpine@sha256:e1506ba20f0cb2af6f23e24c7f8855b417f0b085708acd9b85344a884ba77767 AS run
+
+# Create app directory for unpriviledged user
 RUN mkdir -p /usr/src/app
 WORKDIR /usr/src/app
-COPY --from=0 /usr/src/app/app.jar /usr/src/app/
-COPY --from=0 /usr/src/app/resources /usr/src/app/resources
+
+# Create unpriviledged system user
+RUN adduser --disabled-password --no-create-home --uid 1000 dienstplan
+
+# Copy uber-jar from the build stage
+COPY --from=build /usr/src/app/app.jar /usr/src/app/
+COPY --from=build /usr/src/app/resources /usr/src/app/resources
+RUN chown -R 1000:1000 /usr/src/app
+
+# Run as unpriviledged user
+USER 1000
 CMD ["java", "-jar", "app.jar"]

Dockerfile-test

@@ -1,4 +1,4 @@
-FROM clojure:openjdk-17-lein-bullseye
+FROM clojure:temurin-17-lein-alpine@sha256:37968e7afb62937499c3773e9b713400da4abb358e6beb0ec9bae41a59715111
 RUN mkdir -p /usr/src/app
 COPY project.clj /usr/src/app/
 WORKDIR /usr/src/app

README.md

@@ -1,7 +1,7 @@
 # dienstplan
 
 [![codecov](https://codecov.io/gh/pilosus/dienstplan/branch/main/graph/badge.svg?token=2ouqzEwhLc)](https://codecov.io/gh/pilosus/dienstplan)
-[![Docker Image Version (latest semver)](https://img.shields.io/docker/v/pilosus/dienstplan?label=docker%20image&sort=semver)](https://hub.docker.com/r/pilosus/dienstplan)
+[![Docker Image Version (latest semver)](https://img.shields.io/docker/v/pilosus/dienstplan?label=docker)](https://hub.docker.com/r/pilosus/dienstplan)
 [![Hits-of-Code](https://hitsofcode.com/github/pilosus/dienstplan?branch=main)](https://hitsofcode.com/github/pilosus/dienstplan/view?branch=main)
 
 Slack bot for duty rotations.
@@ -127,8 +127,8 @@ Commands:
 
 ### Server requirements
 
-- Any server with Java 17 or higher (tested with OpenJDK 17)
-- PostgreSQL 9.4 or higher (tested with PostgreSQL 13)
+- Any server with Java 17 or higher (tested with [Eclipse Temurin 17.0.4.1](https://whichjdk.com/#adoptium-eclipse-temurin))
+- PostgreSQL 9.4 to 14.5 (as of 2022-10-29 PostgreSQL 15 is not tested yet)
 - (Optionally) [Sentry account](https://sentry.io/) for error tracking
 
 ### Environment variables

docker-compose.yml

@@ -1,7 +1,7 @@
 version: "3.9"
 services:
   postgres:
-    image: postgres:14-bullseye
+    image: postgres:14.5-alpine3.16@sha256:db802f226b620fc0b8adbeca7859eb203c8d3c9ce5d84870fadee05dea8f50ce
     volumes:
       - "/tmp/diestplan-db-data:/var/lib/postgresql/data"
     env_file:

project.clj

@@ -1,4 +1,4 @@
-(defproject dienstplan "0.2.12"
+(defproject dienstplan "0.3.0-SNAPSHOT"
   :description "Duty rotation slack bot"
   :url "https://github.com/pilosus/dienstplan"
   :license {:name "EPL-2.0 OR GPL-2.0-or-later WITH Classpath-exception-2.0"