Okay really simple you need just a Dockerfile.
# This Dockerfile for a Ruby application was generated by gcloud.
# The base Dockerfile installs:
# * A number of packages needed by the Ruby runtime and by gems
# commonly used in Ruby web apps (such as libsqlite3)
# * A recent version of NodeJS
# * A recent version of the standard Ruby runtime to use by default
# * The bundler and foreman gems
FROM gcr.io/google_appengine/ruby
# Install ruby 2.3.0 if not already preinstalled by the base image
RUN cd /rbenv/plugins/ruby-build && \
git pull && \
rbenv install -s 2.3.0 && \
rbenv global 2.3.0 && \
gem install -q --no-rdoc --no-ri bundler --version 1.11.2 && \
gem install -q --no-rdoc --no-ri foreman --version 0.78.0
ENV RBENV_VERSION 2.3.0
# To install additional packages needed by your gems, uncomment
# the "RUN apt-get update" and "RUN apt-get install" lines below
# and specify your packages.
# RUN apt-get update
# RUN apt-get install imagemagick -y
RUN apt-get update && apt-get install imagemagick -y
# Install required gems.
COPY Gemfile Gemfile.lock /app/
RUN bundle install && rbenv rehash
# Start application on port 8080.
COPY . /app/
ENTRYPOINT bundle exec rackup -p 8080 -E production config.ru
After that just run gcloud preview app deploy
and it will work for you.
Don't forget to change in your app.yaml
runtime: ruby
to runtime: custom
That's it happy coding 🎉