Deployment updates

DEPLOYMENT.md

@@ -0,0 +1,106 @@
+# Deploying your daemons
+
+daemon-kit provides built-in support for
+[Capistrano 3.1+](http://capistranorb.com) deployments. In the past daemon-kit used a modified version of the Rails deployment strategies. Capistrano 3 is much more flexible and allows for a more standard experience.
+
+## Getting started
+
+Add the following to your `Gemfile`
+
+```ruby
+gem 'capistrano', '~> 3.3.3', require: false
+gem 'capistrano-bundler', '~> 1.1.2', require: false
+```
+
+_It is important to have the `require: false` clauses or your daemon will fail to start._
+
+Next up:
+
+```
+$ bundle install
+$ cap install
+```
+
+daemon-kit no longer provides a generator for the capistrano configuration, instead we rely on something very standard :)
+
+Next up, you need to edit the `Capfile` and add the following statements to the file:
+
+```ruby
+require "capistrano/bundler"
+require "daemon_kit/capistrano"
+```
+
+## Configuring capistrano
+
+### Bare minimum
+
+Set the follow two values to get going quickly:
+
+* `application` - name of your application stub in `./bin/`.
+* `deploy_to` - root directory for the deployments.
+
+### daemon-kit configs
+
+Daemon specific deployment configuration is minimal, and optional:
+
+* `daemon_cmd` - defaults to `./bin/:application` where _:application_ is set in the deploy.rb file.
+* `daemon_pid` - defaults to `./log/:application.pid` where _:application_ is set in the deploy.rb
+* `daemon_env` - defaults to `production`
+* `daemon_role` - defaults to `:app` - which Capistrano role the daemon gets deployed to.
+
+Our capistrano code adds the `log` and `tmp` directories to the `:linked_dirs` config of capistrano, ensuring common directories exist during deployment.
+
+## Configuring your daemon
+
+So we want to keep our private configs out of our repositories, but still have the files ready on production so our daemons are configured correctly. The easiest way to achieve this is to have Capistrano symlink those files into the deployed code from the shared directories.
+
+Given our daemon is deployed to `/opt/daemon` by setting the `:deploy_to` value in deploy.rb, we'll get a directory layout that looks roughly like this:
+
+```
+/opt/daemon
+  + current/
+  	 + config/
+  	   - <- SYMLINK TO HERE 
+  + shared/
+    + config/
+      - <- SYMLINK FROM HERE 
+```
+
+By keeping copies of your production configs in capistrano's `:shared_path`, you can add those files to capistrano's `:linked_files` list for symlinking into the project.
+
+For example
+
+```ruby
+set :linked_files, fetch(:linked_files, []).push('config/database.yml')
+```
+
+Will result in something like this:
+
+    /opt/daemon/shared/config/database.yml -> /opt/daemon/current/config/database.yml
+
+### ENV as an alternative
+
+Most of the YAML files used by daemon-kit gets processed with ERB first, so you could also leverage this to render environment variables into the config files for production, and fallback to sensible defaults for development.
+
+## Pulling the trigger
+
+Once your daemon has been configured you can perform deployments by running capistrano like so:
+
+    $ bundle exec cap staging deploy
+
+This will perform the deployment for you and should get you going quickly.
+
+
+## More capistrano resources
+
+To see a list of available commands, please run the following command
+in the root of your project:
+
+    $ cap -vT
+
+For more information on capistrano, please refer to the following list
+of online resources:
+
+* [Capistrano Website](http://www.capistranorb.com)
+* [Capistrano Group](http://groups.google.com/group/capistrano)
+* #capistrano on Freenode

daemon-kit.gemspec

@@ -27,7 +27,7 @@ $ daemon-kit -h
 
   gem.extra_rdoc_files = [
                           "Configuration.txt",
-                          "Deployment.txt",
+                          "DEPLOYMENT.md",
                           "CHANGELOG.md",
                           "Logging.txt",
                           "README.md",

lib/daemon_kit/capistrano.rb

@@ -0,0 +1,85 @@
+namespace :load do
+  task :defaults do
+    set :daemon_default_hooks, -> { true }
+    set :daemon_cmd, -> { "./bin/#{fetch(:application)}" }
+    set :daemon_pid, -> { File.join(shared_path, 'log', "#{fetch(:application)}.pid") }
+    set :daemon_env, "production"
+    set :daemon_role, :app
+
+    # Rbenv and RVM integration
+    # set :rbenv_map_bins, fetch(:rbenv_map_bins).to_a.concat(%w{ puma pumactl })
+    # set :rvm_map_bins, fetch(:rvm_map_bins).to_a.concat(%w{ puma pumactl })
+
+    # Our logs
+    set :linked_dirs, fetch(:linked_dirs, []).push('log', 'tmp')
+  end
+end
+
+namespace :deploy do
+  before :starting, :check_daemon_hooks do
+    invoke 'daemon:add_default_hooks' if fetch(:daemon_default_hooks)
+  end
+end
+
+namespace :daemon do
+
+  desc 'Start daemon'
+  task :start do
+    on roles (fetch(:daemon_role)) do
+      within current_path do
+        with daemon_env: fetch(:daemon_env) do
+
+          execute :bundle, 'exec', fetch(:daemon_cmd), "start --pid #{fetch(:daemon_pid)}"
+        end
+      end
+    end
+  end
+
+  %w[halt stop status].map do |command|
+    desc "#{command} daemon"
+    task command do
+      on roles (fetch(:daemon_role)) do
+        within current_path do
+          with daemon_env: fetch(:daemon_env) do
+            if test "[ -f #{fetch(:daemon_pid)} ]"
+              if test "kill -0 $( cat #{fetch(:daemon_pid)} )"
+                execute :bundle, 'exec', fetch(:daemon_cmd), "#{command} --pid #{fetch(:daemon_pid)}"
+              else
+                # delete invalid pid file , process is not running.
+                execute :rm, fetch(:daemon_pid)
+              end
+            else
+              #pid file not found, so puma is probably not running or it using another pidfile
+              warn 'Daemon not running'
+            end
+          end
+        end
+      end
+    end
+  end
+
+  %w[restart].map do |command|
+    desc "#{command} daemon"
+    task command do
+      on roles (fetch(:daemon_role)) do
+        within current_path do
+          with daemon_env: fetch(:daemon_env) do
+            if test "[ -f #{fetch(:daemon_pid)} ]" and test "kill -0 $( cat #{fetch(:daemon_pid)} )"
+              # NOTE pid exist but state file is nonsense, so ignore that case
+              execute :bundle, 'exec', fetch(:daemon_cmd), "stop --pid #{fetch(:daemon_pid)}"
+            else
+              # Puma is not running or state file is not present : Run it
+              invoke 'daemon:start'
+            end
+          end
+        end
+      end
+    end
+  end
+
+  task :add_default_hooks do
+    #after 'deploy:check', 'puma:check'
+    after 'deploy:finished', 'daemon:restart'
+  end
+
+end