bash - 是否可以将Dockerfile中的ENV变量与正则表达式或包含之类的类似内容进行比较？

Question

我想检查我的VERSION参数，如果正则表达式“。* feature。*”在其中包含“功能”的版本中找到确切的字符串，以生成条件docker镜像。
dockerfile现在看起来像这样:

FROM docker.INSERTURL.com/fe/plattform-nginx:1.14.0-01
ARG ARTIFACTORY_USER
ARG ARTIFACTORY_PW
ARG VERSION

# Download sources from Repository
ADD https://${ARTIFACTORY_USER}:${ARTIFACTORY_PW}@INSERTURL.com/artifactory/api/npm/angular.npm/angular-frontend-app/-/angular-frontend-app-${VERSION}.tgz app.tar.gz

# Extract and move to nginx html folder
RUN tar -xzf app.tar.gz
RUN mv ./package/dist/angular-frontend-app/* /usr/share/nginx/html

# Start nginx via script, which replaces static urls with environment variables
ADD start.sh /usr/share/nginx/start.sh
RUN chmod +x /usr/share/nginx/start.sh

# Overwrite nginx.conf
ADD nginx.conf /etc/nginx/nginx.conf

# Fix permissions for runtime
RUN chmod 777 /var/log/nginx /usr/share/nginx/html

CMD /usr/share/nginx/start.sh

如果VERSION名称中不包含“功能”，我希望它仅从Artifactory下载源。
我想它看起来像这样:

FROM docker.INSERTURL.com/fe/plattform-nginx:1.14.0-01
ARG ARTIFACTORY_USER
ARG ARTIFACTORY_PW
ARG VERSION

if [ "$VERSION" = ".*feature.*" ]; then
     # Download sources from Repository
     ADD https://${ARTIFACTORY_USER}:${ARTIFACTORY_PW}@INSERTURL.com/artifactory/api/npm/angular.npm/angular-frontend-app/-/angular-frontend-app-${VERSION}.tgz app.tar.gz
fi

# Extract and move to nginx html folder
RUN tar -xzf app.tar.gz
RUN mv ./package/dist/angular-frontend-app/* /usr/share/nginx/html

# Start nginx via script, which replaces static urls with environment variables
ADD start.sh /usr/share/nginx/start.sh
RUN chmod +x /usr/share/nginx/start.sh

# Overwrite nginx.conf
ADD nginx.conf /etc/nginx/nginx.conf

# Fix permissions for runtime
RUN chmod 777 /var/log/nginx /usr/share/nginx/html

CMD /usr/share/nginx/start.sh

您知道吗，是否可以使用regex检查Dockerfile ARG和ENV？

Answer 1

Dockerfile中没有条件。您可以在一个RUN步骤中运行任意的Shell代码，但这与您所获得的尽可能接近。
如果您的基本镜像具有HTTP客户端(例如curl)，则可以构建组合命令:

RUN if [ $(expr "$VERSION" : '.*feature.*') -eq 0 ]; then \
     curl -o app.tar.gz https://${ARTIFACTORY_USER}:${ARTIFACTORY_PW}@INSERTURL.com/artifactory/api/npm/angular.npm/angular-frontend-app/-/angular-frontend-app-${VERSION}.tgz \
  && tar -xzf app.tar.gz \
  && mv ./package/dist/angular-frontend-app/* /usr/share/nginx/html \
  && rm -r app.tar.gz package \
; fi

( expr 调用尝试将 $VERSION与该正则表达式匹配，并且不存在任何 \(...\)匹配组，返回匹配的字符数；如果regexp不匹配，则为零。)
您还可以考虑将多个Dockerfile用于不同的变体，或者具有一个安装了此前端应用程序的中间镜像，然后动态选择最终镜像的 FROM行。还要记住，对于最终获得构建图像的任何人，这些凭据将在图像的 docker history中以明文形式可见。