1

鉴于这个多阶段构建的小例子

FROM node:10 AS ui-build
WORKDIR /usr/src/app

FROM node:10 AS server-build
WORKDIR /root/

EXPOSE 3070

ENTRYPOINT ["node"]
CMD ["index.js"]

为什么这会在我的本地文件系统上产生 3 个图像?

"<none>";"<none>";"58d63982fbef";"2020-04-15 17:53:14";"912MB"
"node";"10";"bd83fcefc19d";"2020-04-14 01:32:21";"912MB"
"test";"latest";"3913dd4d03b6";"2020-04-15 17:53:15";"912MB"

我期望有两个图像,基本图像和服务器构建图像。我使用了标准的 docker build 命令,即

docker build -t test . 

那么图像的哪些部分是无的,哪些是测试的?

我很困惑

4

1 回答 1

3

Dockerfile 中以一行开头的每个块都会FROM创建一个新映像。如果您使用docker build -t选项,则只有最后一个阶段会使用您指定的名称进行标记;剩余的块将出现<none>docker images输出等位置。

# node:10 is a base image

# Not the final image, will appear as <none>:<none>
FROM node:10 AS ui-build
...

# The final image, will appear as test:latest (`docker build -t` option)
FROM node:10 AS server-build
...

您偶尔会看到 Dockerfiles,其中基础镜像在后续构建阶段被重用,并且它根本不会出现在docker images输出中。

# Will be hidden because it has descendant images
FROM node:10 AS base
RUN apt-get update && apt-get upgrade

# Will appear as <none>:<none>
FROM base AS ui
...

# Will get the `docker build -t` tag
FROM base
于 2020-04-15T17:43:20.930 回答