安装卷是多阶段构建的一部分

Question

如何安装一个卷来存储我的.m2回购，这样我就不必在每个版本上都下载Internet？

我的构建是一个多阶段构建：

FROM maven:3.5-jdk-8 as BUILD

COPY . /usr/src/app
RUN mvn --batch-mode -f /usr/src/app/pom.xml clean package

FROM openjdk:8-jdk
COPY --from=BUILD /usr/src/app/target /opt/target
WORKDIR /opt/target

CMD ["/bin/bash", "-c", "find -type f -name '*.jar' | xargs java -jar"]

Answer 1

You can do that with Docker >18.09 and BuildKit. You need to enable BuildKit:

export DOCKER_BUILDKIT=1

Then you need to enable experimental dockerfile frontend features, by adding as first line do Dockerfile:

# syntax=docker/dockerfile:experimental

Afterwards you can call the RUN command with cache mount. Cache mounts stay persistent during builds:

RUN --mount=type=cache,target=/root/.m2 \
    mvn --batch-mode -f /usr/src/app/pom.xml clean package