FROM docker.io/alpine:3.20 AS builder

ENV VERSION=25.0.2
ENV SHA256_SUM=c8eb400552174e4b892c4ce9f2114cfee909ef9ebe86f082944b4a0ec47a8825

RUN wget "https://github.com/keycloak/keycloak/releases/download/$VERSION/keycloak-$VERSION.tar.gz"
RUN echo "$SHA256_SUM  keycloak-$VERSION.tar.gz" | sha256sum -c - || exit 1
RUN mkdir -p /keycloak
RUN tar xvf keycloak-$VERSION.tar.gz -C /keycloak --strip 1

FROM docker.io/thallian/alpine-s6:3.20-3.1.6.2

ENV JAVA_OPTS_APPEND="-Djava.net.preferIPv4Stack=false -Djava.net.preferIPv6Addresses=true"

RUN addgroup -g 2222 keycloak
RUN adduser -h /home/keycloak -u 2222 -D -G keycloak keycloak

RUN apk add --no-cache \
	openjdk21-jre-headless \
	bash

COPY --from=builder --chown=keycloak:keycloak /keycloak /home/keycloak/server

RUN /home/keycloak/server/bin/kc.sh build --db=postgres --metrics-enabled=true
RUN chown -R keycloak:keycloak /home/keycloak

ADD /rootfs /