Dump settings from Rakefile

Add 2 new targets:
- gdk.example.yml: Dumps the default configuration to file
- dump_config: Dumps the current configuration to stdout

3 files changed, 118 insertions, 15 deletions

diff --git a/Rakefile b/Rakefile
index 988e9165ed1..a4dea22ef3d 100644
--- a/Rakefile
+++ b/Rakefile
@@ -8,10 +8,29 @@ def config
   @config ||= GDK::Config.new
 end
 
+desc 'Dump the configured settings'
+task 'dump_config' do
+  GDK::Config.new.dump!(STDOUT)
+end
+
+desc 'Generate an example config file with all the defaults'
+file 'gdk.example.yml' do |t|
+  File.open(t.name, File::CREAT|File::TRUNC|File::WRONLY) do |file|
+    config = Class.new(GDK::Config)
+    config.define_method(:gdk_root) { '/home/git/gdk' }
+    config.define_method(:username) { 'git' }
+    config.define_method(:read!) { |_| nil }
+
+    config.new(yaml: {}).dump!(file)
+  end
+end
+
+desc 'Generate Procfile for Foreman'
 file 'Procfile' => ['Procfile.erb', GDK::Config::FILE] do |t|
   GDK::ErbRenderer.new(t.source, t.name).safe_render!
 end
 
+desc 'Generate nginx configuration'
 file 'nginx/conf/nginx.conf' => ['nginx/conf/nginx.conf.erb', GDK::Config::FILE] do |t|
   GDK::ErbRenderer.new(t.source, t.name).safe_render!
 end
diff --git a/gdk.example.yml b/gdk.example.yml
new file mode 100644
index 00000000000..0d93f817c14
--- /dev/null
+++ b/gdk.example.yml
@@ -0,0 +1,61 @@
+---
+gdk_root: "/home/git/gdk"
+username: git
+repositories:
+  gitlab: https://gitlab.com/gitlab-org/gitlab-ce.git
+  gitlab_shell: https://gitlab.com/gitlab-org/gitlab-shell.git
+  gitlab_workhorse: https://gitlab.com/gitlab-org/gitlab-workhorse.git
+  gitaly: https://gitlab.com/gitlab-org/gitaly.git
+  gitaly_proto: https://gitlab.com/gitlab-org/gitaly-proto.git
+  gitlab_pages: https://gitlab.com/gitlab-org/gitlab-pages.git
+  gitlab_docs: https://gitlab.com/gitlab-com/gitlab-docs.git
+gitaly:
+  assembly_dir: "/home/git/gdk/gitaly/assembly"
+gitlab_pages:
+  port: 3034
+  enabled: true
+port: 3000
+registry:
+  port: 5000
+  enabled: false
+  host: 127.0.0.1
+  external_port: 5000
+https: false
+relative_url_root:
+webpack:
+  port: 3806
+object_store:
+  port: 9000
+  enabled: false
+geo:
+  enabled: false
+auto_devops:
+  gitlab:
+    port: 20000
+  enabled: false
+  registry:
+    port: 25000
+tracer:
+  build_tags: tracer_static tracer_static_jaeger
+  jaeger:
+    version: 1.10.1
+    enabled: true
+elasticsearch:
+  version: 6.5.1
+  checksum: 5903e1913a7c96aad96a8227517c40490825f672
+git:
+  bin: "/usr/bin/git"
+nginx:
+  workhorse_port: 3333
+  enabled: false
+  bin: '/usr/sbin/nginx'
+postgresql:
+  bin_dir: "/usr/lib/postgresql/9.6/bin"
+  dir: "/home/git/gdk/postgresql"
+  replication_user: gitlab_replication
+  data_dir: "/home/git/gdk/postgresql/data"
+  replica_dir: "/home/git/gdk/postgresql-replica"
+  geo_dir: "/home/git/gdk/postgresql-geo"
+hostname: localhost
+sshd:
+  bin: '/usr/sbin/sshd'
diff --git a/lib/gdk/config_settings.rb b/lib/gdk/config_settings.rb
index 055886c026a..37a6ffd0b2c 100644
--- a/lib/gdk/config_settings.rb
+++ b/lib/gdk/config_settings.rb
@@ -6,7 +6,7 @@ module GDK
   class ConfigSettings
     SettingUndefined = Class.new(StandardError)
 
-    attr_accessor :parent, :yaml
+    attr_reader :parent, :yaml, :key
 
     def self.method_missing(name, *args, &blk)
       if !args.empty?
@@ -21,24 +21,35 @@ module GDK
 
           sub = Class.new(ConfigSettings)
           blk.call(sub)
-          sub.new(parent: self, yaml: yaml.fetch(name.to_s, {}))
+          sub.new(parent: self, yaml: yaml.fetch(name.to_s, {}), key: [key, name].compact.join('.'))
         end
       else
         raise SettingUndefined, "Could not find the setting '#{name}'"
       end
     end
 
-    # Provide a shorter form for `config.setting.enabled` as `config.setting?`
-    def method_missing(method_name, *args, &blk)
-      enabled = enabled_value(method_name)
+    def initialize(parent: nil, yaml: nil, key: nil)
+      @parent = parent
+      @key = key
+      @yaml = yaml || load_yaml!
+    end
 
-      return super if enabled.nil?
+    def dump!(file = nil)
+      base_methods = ConfigSettings.new.methods
 
-      enabled
-    end
+      yaml = (methods - base_methods).inject({}) do |hash, method|
+        value = public_send(method)
+        if value.is_a?(ConfigSettings)
+          hash[method.to_s] = value.dump!
+        else
+          hash[method.to_s] = value
+        end
+        hash
+      end
 
-    def respond_to_missing?(method_name, include_private = false)
-      !enabled_value(method_name).nil? || super
+      file.puts(yaml.to_yaml) if file
+
+      yaml
     end
 
     def cmd!(cmd)
@@ -58,16 +69,28 @@ module GDK
       value
     end
 
-    def initialize(parent: nil, yaml: nil)
-      @parent = parent
-      @yaml = yaml || load_yaml!
-    end
-
     def root
       parent&.root || self
     end
     alias_method :config, :root
 
+    def inspect
+      "#<GDK::ConfigSettings key:#{key}>"
+    end
+
+    # Provide a shorter form for `config.setting.enabled` as `config.setting?`
+    def method_missing(method_name, *args, &blk)
+      enabled = enabled_value(method_name)
+
+      return super if enabled.nil?
+
+      enabled
+    end
+
+    def respond_to_missing?(method_name, include_private = false)
+      !enabled_value(method_name).nil? || super
+    end
+
     private
 
     def enabled_value(method_name)