Raills App Logs Not working with Docker

I recently switched my rails application from using the Render ruby runtime to using Docker. I’m new to Docker so it’s possible I’m missing something obvious. I was able to deploy my application successfully but now my logs only show the deploy but not of the application logs.

When I check my rails production.rb, it has this check:

  if ENV["RAILS_LOG_TO_STDOUT"].present?
    logger = ActiveSupport::Logger.new($stdout)
    logger.formatter = config.log_formatter
    config.logger = ActiveSupport::TaggedLogging.new(logger)

I have set an environment variable to TRUE (though I believe any value would work). When I open my shell and check, ENV["RAILS_LOG_TO_STDOUT"].present? returns true. Would this not mean rails is logging to stdout and so Render should be displaying these in the logs view?

Apologies if I’m missing something super obvious and thank you for any help.

For reference, here is my render.yaml

  - name: custombuilderselect
    databaseName: custombuilderselect
    user: custombuilderselect

  - type: web
    name: custombuilderselect
    env: docker
    dockerfilePath: ./Dockerfile
      - key: DATABASE_URL
          name: custombuilderselect
          property: connectionString
      - key: RAILS_MASTER_KEY
        sync: false

And my Dockerfile:

# syntax = docker/dockerfile:1

# Make sure RUBY_VERSION matches the Ruby version in .ruby-version and Gemfile
FROM ruby:$RUBY_VERSION-slim as base

# Rails app lives here
WORKDIR /rails

# Set production environment
    BUNDLE_PATH="/usr/local/bundle" \
    BUNDLE_WITHOUT="development:test" \

# Update gems and bundler
RUN gem update --system --no-document && \
    gem install -N bundler

# 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 libpq-dev libvips

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

# Copy application code
COPY --link . .

# 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 bundle exec rails assets:precompile

# Final stage for app image
FROM base

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

# 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 1000:1000 db log storage tmp
USER 1000:1000

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

# Start the server by default, this can be overwritten at runtime
CMD ["./bin/rails", "server"]

I redeployed my application and now its working! Sorry - will remove this.

Edit: I can’t remove my post but please note this is resolved!

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