Dockerfile.privileged

# syntax=docker/dockerfile:1.3-labs

###
# This Dockerfile requires priviledged builder and as such cannot be run usin
# regular `docker build ...`. You need to first create a buildx builder and
# then use it to perform the build:
#
#   docker buildx create --buildkitd-flags '--allow-insecure-entitlement security.insecure' --name privileged-builder
#   docker buildx build --load --builder privileged-builder --allow=security.insecure -f Dockerfile.privileged -t example-spring-boot .
#
###

ARG BASE_IMAGE=ubuntu:24.04
ARG JDK_NAME=zulu22.32.17-ca-crac-jdk22.0.2-linux_x64

FROM $BASE_IMAGE AS builder
ARG JDK_NAME
ENV JAVA_HOME=/usr/share/$JDK_NAME
ENV ENDPOINT=http://localhost:8080

RUN apt-get update && apt-get install -y curl maven siege wget
RUN wget -O crac-jdk.tar.gz https://cdn.azul.com/zulu/bin/$JDK_NAME.tar.gz
RUN tar zxf ./crac-jdk.tar.gz -C /usr/share

ADD . /example-spring-boot
RUN cd /example-spring-boot && mvn -B install && mv target/example-spring-boot-0.0.1-SNAPSHOT.jar /example-spring-boot.jar

RUN --security=insecure <<END_OF_SCRIPT
#!/bin/bash

# Start the process in background. We are adding -XX:CRaCMinPid to explicitly
# offset PIDs (needed for unprivileged restore) as the process started from
# this script won't be running as PID 1, disabling the built-in offsetting.
$JAVA_HOME/bin/java -XX:CPUFeatures=generic -XX:CRaCMinPid=128 -XX:CRaCCheckpointTo=/cr -jar /example-spring-boot.jar &
PID=$!
# Wait until the connection is opened
until curl --output /dev/null --silent --head --fail $ENDPOINT; do
    sleep 0.1
done
# Warm-up the server by executing 100k requests against it
siege -c 1 -r 100000 -b $ENDPOINT
# Do the checkpoint
$JAVA_HOME/bin/jcmd /example-spring-boot.jar JDK.checkpoint
# Wait until the process completes, returning success (wait would return exit code 137)
wait $PID || true

END_OF_SCRIPT

FROM $BASE_IMAGE
ARG JDK_NAME
ENV JAVA_HOME=/usr/share/$JDK_NAME
ENV PATH="$PATH:$JAVA_HOME/bin"

COPY --from=builder /usr/share/${JDK_NAME} /usr/share/${JDK_NAME}
COPY --from=builder /cr /cr
COPY --from=builder /example-spring-boot.jar /example-spring-boot.jar
CMD [ "java", "-XX:CRaCRestoreFrom=/cr" ]