Bdtjtk

I am trying to "dockerize" an existing Rails development app. This is my first time experimenting with Docker.

I want to set up Guard to listen for file changes and run relevant specs.

The Guard service appears to be running correctly, and the logs show:

guard_1     | 16:35:12 - INFO - Guard is now watching at '/app'

But when I edit/save spec files Guard is not running any tests.

This is an existing app that I'm moving into Docker. It has a guardfile that works outside of Docker.

I've searched and read a number of posts (e.g. this one), but I'm not sure where to start debugging this. Can anyone point me in the right direction and get Guard listening to file changes.

My docker-compose.yml looks like this:

version: '3'



services:

  postgres:

    ports:

      - "5432:5432"

    volumes:

      - $HOME/postgres-data:/var/lib/postgresql

    image: postgres:9.6.9



  redis:

    ports:

      - "6379:6379"

    depends_on:

      - postgres

    image: redis:5.0-rc



  web:

    build: .

    ports:

      - "3000:3000"

    command: /bin/sh -c "rails s -b 0.0.0.0 -p 3000"

    depends_on:

      - postgres

      - redis

    env_file:

      - .env



  guard:

    build: .

    env_file:

      - .env

    command: bundle exec guard --no-bundler-warning --no-interactions



  sidekiq:

    build: .

    command: bundle exec sidekiq -C config/sidekiq.yml

    depends_on:

      - postgres

      - redis

    env_file:

      - .env



volumes:

  redis:

  postgres:

  sidekiq:

  guard:

Guardfile

guard 'spring', bundler: true do

  watch('Gemfile.lock')

  watch(%r{^config/})

  watch(%r{^spec/(support|factories)/})

  watch(%r{^spec/factory.rb})

end



guard :rspec, cmd: "bundle exec rspec" do

  require "guard/rspec/dsl"

  dsl = Guard::RSpec::Dsl.new(self)



  # RSpec files

  rspec = dsl.rspec

  watch(rspec.spec_files)



  # Ruby files

  ruby = dsl.ruby

  dsl.watch_spec_files_for(ruby.lib_files)



  # Rails files

  rails = dsl.rails(view_extensions: %w(erb haml slim))

  dsl.watch_spec_files_for(rails.app_files)

  dsl.watch_spec_files_for(rails.views)



  watch(rails.controllers) do |m|

    [

      rspec.spec.call("routing/#{m[1]}_routing"),

      rspec.spec.call("controllers/#{m[1]}_controller"),

      rspec.spec.call("acceptance/#{m[1]}")

    ]

  end



  # Rails config changes

  watch(rails.spec_helper)     { rspec.spec_dir }

  watch(rails.routes)          { "#{rspec.spec_dir}/routing" }

  watch(rails.app_controller)  { "#{rspec.spec_dir}/controllers" }



  # Capybara features specs

  watch(rails.view_dirs)     { |m| rspec.spec.call("features/#{m[1]}") }

  watch(rails.layouts)       { |m| rspec.spec.call("features/#{m[1]}") }



  # Turnip features and steps

  watch(%r{^spec/acceptance/(.+).feature$})

  watch(%r{^spec/acceptance/steps/(.+)_steps.rb$}) do |m|

    Dir[File.join("**/#{m[1]}.feature")][0] || "spec/acceptance"

  end

  ignore %r{^spec/support/concerns/}

end



guard 'brakeman', :run_on_start => true do

  watch(%r{^app/.+.(erb|haml|rhtml|rb)$})

  watch(%r{^config/.+.rb$})

  watch(%r{^lib/.+.rb$})

  watch('Gemfile')

end

I'm assuming you're making changes on your local filesystem and expected guard, inside the container, to trigger.

If so, the missing link is your docker-compose.yml file.

guard:

  build: .

  env_file:

    - .env

  command: bundle exec guard --no-bundler-warning --no-interactions

  volumes:

    - .:/app

You need to mount the volume of your root (Rails root) directory inside the container so that the changes are reflected. Without this line, your container(s) only sees what was available at build time, and not the changes.

I faced the exact same problem and have been wondering about existing solutions that didn't really work. The key solution to your problem (if you are on OSX of course) is to understand the difference between "Docker Toolbox" and "Docker for Mac".

This article gives a lot of insight: https://docs.docker.com/docker-for-mac/docker-toolbox/

TL;DR

If you are on Mac, you need to use Docker for Mac to have the benefits of osxfs. If you do this you will not need docker-sync!