如何设置 Docker 与 gitlab-ci 一起用于裸机项目？

Question

我是 docker 的新手，目前正在尝试使用它来编译一个裸机项目。 Dockerfile 看起来像这样：

FROM ubuntu:22.04 AS base

ARG BUILD_TYPE=Release
ARG BUILD_DIR=build

RUN apt-get update && apt-get install -y \
    gdb-multiarch \
    wget \
    xz-utils \
    make cmake ninja-build bzip2 mc file

RUN mkdir /usr/opt/

RUN wget --directory-prefix=/usr/opt/ https://developer.arm.com/-/media/Files/downloads/gnu-rm/10.3-2021.10/gcc-arm-none-eabi-10.3-2021.10-aarch64-linux.tar.bz2
RUN mkdir -p /usr/opt/gcc-arm-none-eabi
RUN tar -xvjf /usr/opt/gcc-arm-none-eabi-10.3-2021.10-aarch64-linux.tar.bz2 -C /usr/opt/gcc-arm-none-eabi --strip-components=1
RUN ln -s /usr/opt/gcc-arm-none-eabi/bin/arm-none-eabi-gcc /usr/bin/arm-none-eabi-gcc
RUN ln -s /usr/opt/gcc-arm-none-eabi/bin/arm-none-eabi-ar /usr/bin/arm-none-eabi-ar
RUN ln -s /usr/opt/gcc-arm-none-eabi/bin/arm-none-eabi-as /usr/bin/arm-none-eabi-as
RUN ln -s /usr/opt/gcc-arm-none-eabi/bin/arm-none-eabi-ld /usr/bin/arm-none-eabi-ld
RUN ln -s /usr/opt/gcc-arm-none-eabi/bin/arm-none-eabi-objcopy /usr/bin/arm-none-eabi-objcopy

ENV CC="/usr/bin/arm-none-eabi-gcc"
ENV CXX="/usr/bin/arm-none-eabi-gcc"

WORKDIR /home/project

COPY . .

FROM base AS build
RUN cmake -G Ninja -B ./${BUILD_DIR} -S .
RUN cmake --build ./${BUILD_DIR}

FROM scratch AS export-stage
COPY --from=build ./home/project/build/bin .

我通过

构建它

DOCKER_BUILDKIT=1 docker build --progress=plain -f Dockerfile --rm -t project:latest . --output ./export/

实际上，这意味着最后，

build/bin

的内容将从 Docker img 复制到我的本地机器。所有这些都非常好用！

我使用 gitlab 进行源代码控制，我想使用

.gitlab-ci.yml

构建我的项目并查看它是否编译，即在

RUN cmake --build ./${BUILD_DIR}

命令后停止。

我试着写一个相应的

.gitlab-ci.yml

文件，即

docker-build:
  image: docker:latest
  stage: build
  services:
    - docker:dind
  script:
    - |
      if [[ "$CI_COMMIT_BRANCH" == "$CI_DEFAULT_BRANCH" ]]; then
        tag=""
        echo "Running on default branch '$CI_DEFAULT_BRANCH': tag = 'latest'"
      else
        tag=":$CI_COMMIT_REF_SLUG"
        echo "Running on branch '$CI_COMMIT_BRANCH': tag = $tag"
      fi
    - DOCKER_BUILDKIT=1 docker build --progress=plain -f Dockerfile --rm -t project:latest . --output ./export/
  rules:
    - if: $CI_COMMIT_BRANCH
      exists:
        - Dockerfile

但这每次都会重建整个 Docker-img，而不是仅仅执行

FROM base AS build
RUN cmake -G Ninja -B ./${BUILD_DIR} -S .
RUN cmake --build ./${BUILD_DIR}

如果什么都没有改变，

base

应该被“缓存”...这可以在 gitlab-ci` 中完成，还是我误解了它是如何工作的？