我已经对 Rails 应用程序进行了多级 Docker 化，但图像大小超过 600mb，太大了。
Dockerfile
# Dockerfile for local development.
# Default Ruby version for this project.
ARG RUBY_VERSION=3.1.0
# Base image
FROM ruby:$RUBY_VERSION-alpine AS base
# Set environment variables for the username,
# app directory, and the language.
ENV USER app
ENV APP_DIR /app
# Set env variables for dev
ENV BUNDLER_VERSION 2.3.3
ENV GEM_HOME=/usr/local/bundle
ENV BUNDLE_PATH=$GEM_HOME
ENV BUNDLE_APP_CONFIG=$BUNDLE_PATH
ENV BUNDLE_JOBS 4
ENV BUNDLE_RETRY 3
ENV RAILS_ENV development
ENV RACK_ENV development
ENV PATH=$APP_DIR/bin:$PATH
ENV LANG C.UTF-8
# Add PostgreSQL, timezone libraries,
# and git for development.
RUN apk add --no-cache --update \
libpq-dev \
tzdata \
git \
&& rm -rf /var/cache/apk/*
# Start building a new image called "dependencies"
# from the "base" image.
FROM base AS dependencies
# Add libraries required for installing gems.
RUN apk add --no-cache --update \
build-base \
&& rm -rf /var/cache/apk/*
# Copy the Gemfile and Gemfile.lock
# files to the current directory.
COPY Gemfile Gemfile.lock ./
# Install bundler with specified version.
RUN gem install bundler -v $BUNDLER_VERSION
# "frozen" option means that the exact versions of gems
# specified in the Gemfile.lock file will be used,
# and any updates to those gems will be ignored.
#
# Install gems with ENV options from above,
# remove unnecessary files from gems.
RUN bundle config --global frozen 1 && \
bundle install && \
rm -rf $BUNDLE_PATH/cache/*.gem && \
rm -rf $BUNDLE_PATH/ruby/*/cache && \
find $BUNDLE_PATH/gems/ -name "*.c" -delete && \
find $BUNDLE_PATH/gems/ -name "*.o" -delete
# Start building a new image from the "base" image.
FROM base
# Copy entrypoint, make it executable.
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
# Add new user in the system.
RUN adduser -D $USER
# Create directory for rails application,
# set user as the owner.
RUN mkdir -p $APP_DIR && \
chown $USER $APP_DIR
# Set the working directory to the app directory.
WORKDIR $APP_DIR
# Switch from root to specified user.
USER $USER
# Copy the bundle directory from the "dependencies"
# image and copy all files to the current directory,
# setting the ownership to the specified user.
COPY --from=dependencies $BUNDLE_PATH $BUNDLE_PATH
COPY --chown=$USER . ./
# Expose port 3000 for the application.
EXPOSE 3000
# Run the command to start the Rails server.
CMD ["rails", "s", "-b", "0.0.0.0"]
如何进行更改以缩小图像尺寸？
您可以使用 libpq 而不是 libpq-dev。
使用
docker history image但我认为你的捆绑层占用了大部分容量。
参考：