feat(docker): switch to openjdk:8-alpine version

Dockerfile

@@ -1,10 +1,9 @@
-FROM openjdk:8
+FROM openjdk:8-alpine
 LABEL maintainer="info@ninjaneers.de"
 LABEL "author"="Dennis Fricke"
 LABEL "company"="Ninjaneers GmbH"
 
-RUN  apt-get update -y && apt-get install -y unzip \
-    && rm -rf /var/lib/apt/lists/*
+RUN  apk update && apk add unzip
 
 ADD https://ec.europa.eu/cefdigital/artifact/repository/esignaturedss/eu/europa/ec/joinup/sd-dss/dss-demo-bundle/5.5/dss-demo-bundle-5.5.zip /tmp
 RUN unzip /tmp/dss-demo-bundle-5.5.zip -d /tmp

README.md

@@ -1,9 +1,15 @@
-# Docker container for eSignature of CEF Digital
+# Docker container for Digital Signature Service (eSignature) of CEF Digital
 
-see [eSignature Service](https://ec.europa.eu/cefdigital/wiki/display/CEFDIGITAL/DSS)
+This Dockerfile will provide the current Digital Signature Service Demo of CEF in version 5.5
 
+@see [eSignature Service](https://ec.europa.eu/cefdigital/wiki/display/CEFDIGITAL/DSS)
 
+## Usage
 
-## Docker Hub
+### Docker run
+`docker run --rm --ti -p 8080:8080 ninjaneers/dss:latest`
 
-[Repository](https://hub.docker.com/r/ninjaneers/dss)
+
+### Docker Compose
+
+`docker-compose up` will expose DSS on http://localhost:8080

docker-compose.yml

@@ -0,0 +1,7 @@
+version: '3.6'
+
+services:
+  dss:
+    image: 'ninjaneers/dss:latest'
+    ports:
+      - '8080:8080'