Body:

I am trying to build my Docker container using the following command:

docker build --no-cache -t cryptoall .

But I am consistently getting this error:

43.55 (net-protocol (>= 0)).
43.55 Running `bundle update net-pop` should fix the problem.
------
Dockerfile:51
--------------------
 50 |     COPY Gemfile Gemfile.lock ./
 51 | >>> RUN bundle update net-pop && \
 52 | >>>     bundle install && \
 53 | >>>     rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
 54 | >>>     bundle exec bootsnap precompile --gemfile
 55 |     
--------------------
ERROR: failed to solve: process "/bin/sh -c bundle update net-pop &&     bundle install &&     rm -rf ~/.bundle/ \"${BUNDLE_PATH}\"/ruby/*/cache \"${BUNDLE_PATH}\"/ruby/*/bundler/gems/*/.git &&     bundle exec bootsnap precompile --gemfile" did not complete successfully: exit code: 34

Dockerfile:

# syntax=docker/dockerfile:1

# This Dockerfile is designed for production, not development. Use with Kamal or 
# build'n'run by hand:
# docker build -t cryptoall .
# docker run -d -p 80:80 -e RAILS_MASTER_KEY=<value from config/master.key> --name 
# cryptoall cryptoall

# For a containerized dev environment, see Dev Containers: 
# .html

# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
ARG RUBY_VERSION=3.3.3
FROM docker.io/library/ruby:$RUBY_VERSION-slim AS base

# Rails app lives here
WORKDIR /rails

# Install base packages
RUN apt-get update -qq && \
    apt-get install --no-install-recommends -y curl libjemalloc2 libvips postgresql-client && \
    rm -rf /var/lib/apt/lists /var/cache/apt/archives

# Set production environment
ENV RAILS_ENV="production" \
    BUNDLE_DEPLOYMENT="1" \
    BUNDLE_PATH="/usr/local/bundle" \
    BUNDLE_WITHOUT="development"

# Throw-away build stage to reduce size of final image
FROM base AS build

# Install packages needed to build gems, including dependencies for Nokogiri and others
RUN apt-get update -qq && \
    apt-get install --no-install-recommends -y \
      build-essential \
      libpq-dev \
      nodejs \
      npm \
      git \
      pkg-config \
      libxml2-dev \
      libxslt1-dev \
      liblzma-dev \
      libcurl4-openssl-dev \
      libssl-dev && \
    rm -rf /var/lib/apt/lists/* /var/cache/apt/archives/*

# Install the correct version of Bundler
RUN gem install bundler -v 2.5.23

# Install application gems
COPY Gemfile Gemfile.lock ./
RUN bundle update net-pop && \
    bundle install && \
    rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
    bundle exec bootsnap precompile --gemfile

# Verify the rails executable is installed
RUN bundle exec rails --version

# Copy application code
COPY . /rails

# Precompile bootsnap code for faster boot times
RUN bundle exec bootsnap precompile app/ lib/

# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
# Use a dummy key for precompiling, this can be set during deployment
RUN SECRET_KEY_BASE_DUMMY=1 bundle exec rails assets:precompile

# Final stage for app image
FROM base

# Copy built artifacts: gems, application
COPY --from=build "${BUNDLE_PATH}" "${BUNDLE_PATH}"
COPY --from=build /rails /rails

# Verify the rails executable is copied
RUN ls -l /rails/bin/rails

# Run and own only the runtime files as a non-root user for security
RUN groupadd --system --gid 1000 rails && \
    useradd rails --uid 1000 --gid 1000 --create-home --shell /bin/bash && \
    chown -R rails:rails /rails/db /rails/log /rails/storage /rails/tmp
USER rails

# Entrypoint prepares the database.
ENTRYPOINT ["/rails/bin/docker-entrypoint"]

# Start server via Thruster by default, this can be overwritten at runtime
EXPOSE 80
CMD ["bundle", "exec", "/rails/bin/rails", "server", "-b", "0.0.0.0"]
Error Summary:
The build fails at the following step in the Dockerfile:

dockerfile
Copy
Edit
RUN bundle update net-pop && \
    bundle install && \
    rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
    bundle exec bootsnap precompile --gemfile
The error message suggests that running bundle update net-pop should resolve the issue. However, when I run the Docker build command, it fails consistently with an exit code 34.

What I’ve tried: I’ve tried using the bundle update net-pop command directly and updating other gems as well. I also ensured I have the correct version of Bundler installed (version 2.5.23). Could anyone suggest how to fix this issue or if there is anything missing in my Dockerfile?