#8. nginx+puma deployment using capistrano

 In the Gemfile,

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group :development do

  gem 'capistrano',         require: false

  gem 'capistrano-rvm',     require: false

  gem 'capistrano-rails',   require: false

  gem 'capistrano-bundler', require: false

  gem 'capistrano3-puma',   require: false

end

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bundle install

cap install

create a file as, 
/home/raj/workspace/chat/config/nginx.conf

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upstream puma {

  server unix:///home/raj/deployed_apps/chat/shared/tmp/sockets/chat-puma.sock;

}

server {

  listen 80 default_server deferred;

  # server_name example.com;

  root /home/raj/deployed_apps/chat/current/public;

  access_log /home/raj/deployed_apps/chat/current/log/nginx.access.log;

  error_log /home/raj/deployed_apps/chat/current/log/nginx.error.log info;

  location ^~ /assets/ {

    gzip_static on;

    expires max;

    add_header Cache-Control public;

  }

  try_files $uri/index.html $uri @puma;

  location @puma {

    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    proxy_set_header Host $http_host;

    proxy_redirect off;

    proxy_pass http://puma;

  }

  error_page 500 502 503 504 /500.html;

  client_max_body_size 10M;

  keepalive_timeout 10;

}

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In the deploy.rb,

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server '192.168.42.28', port: 22, roles: [:web, :app, :db], primary: true

set :repo_url,        'ssh://git@code.bitbucket.org:7999/tran/chat.git'

set :application,     'chat'

set :user,            'raj'

set :puma_threads,    [4, 16]

set :puma_workers,    0

# Don't change these unless you know what you're doing

set :pty,             true

set :use_sudo,        false

set :stage,           :production

set :deploy_via,      :remote_cache

set :deploy_to,       "/home/#{fetch(:user)}/deployed_apps/#{fetch(:application)}"

set :puma_bind,       "unix://#{shared_path}/tmp/sockets/#{fetch(:application)}-puma.sock"

set :puma_state,      "#{shared_path}/tmp/pids/puma.state"

set :puma_pid,        "#{shared_path}/tmp/pids/puma.pid"

set :puma_access_log, "#{release_path}/log/puma.error.log"

set :puma_error_log,  "#{release_path}/log/puma.access.log"

set :ssh_options,     { forward_agent: true, user: fetch(:user), keys: %w(~/.ssh/id_rsa.pub) }

set :puma_preload_app, true

set :puma_worker_timeout, nil

set :puma_init_active_record, true  # Change to false when not using ActiveRecord

## Defaults:

# set :scm,           :git

set :branch,        'rk-tmp'

# set :format,        :pretty

# set :log_level,     :debug

# set :keep_releases, 5

## Linked Files & Directories (Default None):

# set :linked_files, %w{config/database.yml}

# set :linked_dirs,  %w{bin log tmp/pids tmp/cache tmp/sockets vendor/bundle public/system}

namespace :puma do

  desc 'Create Directories for Puma Pids and Socket'

  task :make_dirs do

    on roles(:app) do

      execute "mkdir #{shared_path}/tmp/sockets -p"

      execute "mkdir #{shared_path}/tmp/pids -p"

    end

  end

  before :start, :make_dirs

end

namespace :deploy do

  desc "Make sure local git is in sync with remote."

  task :check_revision do

    on roles(:app) do

      unless `git rev-parse HEAD` == `git rev-parse origin/rk-tmp`

        puts "WARNING: HEAD is not the same as origin/master"

        puts "Run `git push` to sync changes."

        exit

      end

    end

  end

  desc 'Initial Deploy'

  task :initial do

    on roles(:app) do

      before 'deploy:restart', 'puma:start'

      invoke 'deploy'

    end

  end

  desc 'Restart application'

  task :restart do

    on roles(:app), in: :sequence, wait: 5 do

      invoke 'puma:restart'

    end

  end

  before :starting,     :check_revision

  after  :finishing,    :compile_assets

  after  :finishing,    :cleanup

  after  :finishing,    :restart

end

# ps aux | grep puma    # Get puma pid

# kill -s SIGUSR2 pid   # Restart puma

# kill -s SIGTERM pid   # Stop puma

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Modify Capfile as,

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require 'capistrano/setup'

require 'capistrano/deploy'

require "capistrano/scm/git"

install_plugin Capistrano::SCM::Git

require 'capistrano/rails'

require 'capistrano/bundler'

require 'capistrano/rvm'

require 'capistrano/puma'

install_plugin Capistrano::Puma

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# Loads custom tasks from `lib/capistrano/tasks' if you have any defined.

Dir.glob('lib/capistrano/tasks/*.rake').each { |r| import r }

cap production deploy:initial --trace

sudo ln -nfs "/home/raj/deployed_apps/chat/current/config/nginx.conf" "/etc/nginx/sites-enabled/chat"

sudo service nginx restart

systemctl status nginx.service

Now visit,
http://192.168.42.28