多阶段 dockerfile 跳过阶段

Question

我正在尝试构建具有以下阶段的多阶段 docker 文件，但所有阶段都在执行。

即使我在 docker build

中指定了 EXECUTION_ENV=local，我总是会执行 git 克隆

Docker文件:

ARG GIT_TOKEN=abc:1a2b3
ARG EXECUTION_ENV=local

# get dependencies from github
FROM alpine/git as gitclone-ci
WORKDIR /usr/src/
RUN git clone https://{GIT_USER_TOKEN}@github.com/something.git \
    && git clone https://{GIT_USER_TOKEN}@github.com/somethingelse.git

## in local dependencies are already available in the parent folder
FROM alpine/git as gitclone-local
WORKDIR /usr/src/
COPY ../something /usr/src/something 
COPY ../somethingelse /usr/src/somethingelse

FROM node:latest as builder
WORKDIR /usr/src
COPY --from=gitclone-${EXECUTION_ENV} /usr/src .
COPY package* ./
COPY src/ src/
RUN ["npm", "install"]

Docker 尝试构建命令：

docker build -t somecontainer --build-arg GIT_TOKEN=abc:123 --build-arg EXECUTION_ENV=local.

docker build -t somecontainer --target builder --build-arg GIT_TOKEN=abc:123 --build-arg EXECUTION_ENV=local.

注：如果我在 docker 守护程序中启用 "features": { "buildkit": true} 并在 cmd docker build -t somecontainer --build-arg GIT_TOKEN=abc:123 --build-arg EXECUTION_ENV=local. 中启用运行我会收到以下错误

failed to solve with frontend dockerfile.v0: failed to create LLB definition: failed to parse stage name "gitclone-$EXECUTION_ENV": invalid reference format: repository name must be lowercase

Answer 1

跳过阶段仅适用于 BuildKit。请参阅讨论 here and article here。

至于你得到的错误，你应该在有或没有 BuildKit 的情况下得到它，因为你不能在 COPY 指令中使用构建参数。不同之处在于，使用 BuildKit Docker 甚至会拒绝启动构建，而没有它，构建将在 COPY 指令上失败。

您需要做的是使用 FROM 指令解析构建参数的事实为要复制的图像创建一个额外的别名：

ARG GIT_TOKEN=abc:1a2b3
ARG EXECUTION_ENV=local

# get dependencies from github
FROM alpine/git as gitclone-ci
WORKDIR /usr/src/
RUN git clone https://{GIT_USER_TOKEN}@github.com/something.git \
    && git clone https://{GIT_USER_TOKEN}@github.com/somethingelse.git

## in local dependencies are already available in the parent folder
FROM alpine/git as gitclone-local
WORKDIR /usr/src/
COPY ../something /usr/src/something 
COPY ../somethingelse /usr/src/somethingelse

FROM gitclone-${EXECUTION_ENV} as intermediate

FROM node:latest as builder
WORKDIR /usr/src
COPY --from=intermediate /usr/src .
COPY package* ./
COPY src/ src/
RUN ["npm", "install"]

多阶段 dockerfile 跳过阶段

Multistage dockerfile skip stages

docker

dockerfile

docker-multi-stage-build