bootsnap precompile and rails assets:precompile commands cause error when building Docker image

[rgxcp]

Steps to reproduce

# Create a new Rails app
gem install rails -v 8.0.1
rails new my-app -d postgresql

# Build Docker image using generated Dockerfile file
docker build --platform linux/amd64 --rm --tag my-app:latest .

Expected behavior

The Docker image build process is success.

Actual behavior

The Docker image build process is failed with the following error:

67.57 bundler: failed to load command: bootsnap (/usr/local/bundle/ruby/3.4.0/bin/bootsnap)
67.57 /usr/local/lib/ruby/3.4.0/bundler/definition.rb:676:in 'Bundler::Definition#materialize': Could not find net-smtp-0.5.0 in locally installed gems (Bundler::GemNotFound)
67.57   from /usr/local/lib/ruby/3.4.0/bundler/definition.rb:232:in 'Bundler::Definition#specs'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/definition.rb:299:in 'Bundler::Definition#specs_for'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/runtime.rb:18:in 'Bundler::Runtime#setup'
67.57   from /usr/local/lib/ruby/3.4.0/bundler.rb:167:in 'Bundler.setup'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/setup.rb:32:in 'block in <top (required)>'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/ui/shell.rb:173:in 'Bundler::UI::Shell#with_level'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/ui/shell.rb:119:in 'Bundler::UI::Shell#silence'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/setup.rb:32:in '<top (required)>'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli/exec.rb:57:in 'Kernel#require_relative'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli/exec.rb:57:in 'Bundler::CLI::Exec#kernel_load'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli/exec.rb:23:in 'Bundler::CLI::Exec#run'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli.rb:452:in 'Bundler::CLI#exec'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/vendor/thor/lib/thor/command.rb:28:in 'Bundler::Thor::Command#run'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/vendor/thor/lib/thor/invocation.rb:127:in 'Bundler::Thor::Invocation#invoke_command'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/vendor/thor/lib/thor.rb:538:in 'Bundler::Thor.dispatch'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli.rb:35:in 'Bundler::CLI.dispatch'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/vendor/thor/lib/thor/base.rb:584:in 'Bundler::Thor::Base::ClassMethods#start'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/cli.rb:29:in 'Bundler::CLI.start'
67.57   from /usr/local/lib/ruby/gems/3.4.0/gems/bundler-2.6.2/exe/bundle:28:in 'block in <top (required)>'
67.57   from /usr/local/lib/ruby/3.4.0/bundler/friendly_errors.rb:117:in 'Bundler.with_friendly_errors'
67.57   from /usr/local/lib/ruby/gems/3.4.0/gems/bundler-2.6.2/exe/bundle:20:in '<top (required)>'
67.57   from /usr/local/bin/bundle:25:in 'Kernel#load'
67.57   from /usr/local/bin/bundle:25:in '<main>'
------
Dockerfile:38
--------------------
  37 |     COPY Gemfile Gemfile.lock ./
  38 | >>> RUN bundle install && \
  39 | >>>     rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
  40 | >>>     bundle exec bootsnap precompile --gemfile
  41 |
--------------------
ERROR: failed to solve: process "/bin/sh -c 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: 1

System configuration

Rails version: 8.0.1

Ruby version: 3.4.1

Notes

After hours of trial and error, I found these 3 lines that caused the error:

bundle exec bootsnap precompile --gemfile
bundle exec bootsnap precompile app/ lib/
SECRET_KEY_BASE_DUMMY=1 ./bin/rails assets:precompile

If I remove those 3 lines the build process is success.

My full Dockerfile (basically it just a standard generated Dockerfile from Rails, nothing changed):

# syntax=docker/dockerfile:1
# check=error=true

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

# For a containerized dev environment, see Dev Containers: https://guides.rubyonrails.org/getting_started_with_devcontainer.html

# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
ARG RUBY_VERSION=3.4.1
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
RUN apt-get update -qq && \
    apt-get install --no-install-recommends -y build-essential git libpq-dev pkg-config && \
    rm -rf /var/lib/apt/lists /var/cache/apt/archives

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

# Copy application code
COPY . .

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

# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
RUN SECRET_KEY_BASE_DUMMY=1 ./bin/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

# 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 db log storage tmp
USER 1000:1000

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

# Start server via Thruster by default, this can be overwritten at runtime
EXPOSE 80
CMD ["./bin/thrust", "./bin/rails", "server"]

[byroot]

This is a bug in Ruby itself: https://bugs.ruby-lang.org/issues/21113

Try bundle update net-smtp, that should install the 0.5.1 version and solve your issue.

[wenweih]

I encountered the same issue. Thank you, @byroot, for providing the solution and fixing the bug!

[jorgegonzalez]

Getting this same issue and updating net-smtp did not seem to resolve this. Any guidance?