- Make configs inheritable and other goodies in this prototype

Example:
    % RUBYLIB=lib ruby -rubygems -e 'require "logstash/config";  require "logstash/inputs/file"; require "logstash/inputs/amqp"; LogStash::Inputs::Amqp.dsl_gen; LogStash::Inputs::File.dsl_gen'
    input { #parent
      amqp { #node
        "somename":
          tag => string,
          path => string,
          pantscon => string,
      } #node
    } #parent
    input { #parent
      file { #node
        "somename":
          tag => string,
          path => string,
      } #node
    } #parent

lib/logstash/config.rb

@@ -23,20 +23,59 @@ module LogStash::Config
   # This method is called when someone does 'include LogStash::Config'
   def self.included(base)
     # Add ClassMethods module methods to the 'base' given.
-    base.extend(ClassMethods)
+    base.extend(LogStash::Config::DSL)
   end
 
-  module ClassMethods
+  module DSL
-    def section(name)
+    attr_accessor :dsl_name
-      @section = name
+    attr_accessor :dsl_parent
-    end # def self.section
 
-    def config(cfg)
+    # Set the parent config for this class.
+    def dsl_parent(*args)
+      @dsl_parent = args[0] if args.length > 0
+      return @dsl_parent
+    end
+
+    # Set the config name for this class.
+    def dsl_name(*args)
+      @dsl_name = args[0] if args.length > 0
+      return @dsl_name
+    end
+
+    def dsl_config(cfg)
       # cfg should be hash with one entry of { "key" => "val" }
+      @dsl_config ||= Hash.new
       key, value = cfg.to_a.first
-      puts "#{@section} {"
+      @dsl_config[key] = value
-      puts "  #{key} => #{value}"
+    end # def config
-      puts "}"
+
-    end # def self.config
+    def dsl_gen
-  end # module ClassMethods
+      puts "#{@dsl_parent.dsl_name} { #parent" if @dsl_parent
+      config = []
+      config << "#{@dsl_name} { #node"
+      config << "  \"somename\":"
+      attrs = []
+      (@dsl_config || Hash.new).each do |key, value|
+        attrs << "    #{key} => #{value},"
+      end
+      config += attrs
+      config << "} #node"
+      config = config.collect { |p| "#{@dsl_parent.nil? ? "" : "  "}#{p}" }
+      puts config.join("\n")
+      puts "} #parent" if @dsl_parent
+    end
+
+    def inherited(subclass)
+      # Copy our parent's config to a subclass.
+      # This method is invoked whenever someone subclasses us, like:
+      # class Foo < Bar ...
+      config = Hash.new
+      @dsl_config.each do |key, val|
+        #puts "#{self}: Sharing config '#{key}' with subclass #{subclass}"
+        config[key] = val
+      end
+      subclass.instance_variable_set("@dsl_config", config)
+      subclass.dsl_parent = self
+    end # def inherited
+  end # module LogStash::Config::DSL
 end # module LogStash::Config

lib/logstash/inputs/amqp.rb

@@ -8,6 +8,9 @@ require "cgi"
 class LogStash::Inputs::Amqp < LogStash::Inputs::Base
   MQTYPES = [ "fanout", "queue", "topic" ]
 
+  dsl_name "amqp"
+  dsl_config "pantscon" => :string #LogStash::Config::Path
+
   public
   def initialize(url, type, config={}, &block)
     super

lib/logstash/inputs/base.rb

@@ -8,9 +8,11 @@ class LogStash::Inputs::Base
   include LogStash::Config
   attr_accessor :logger
 
+  dsl_name "input"
+  dsl_parent nil
   # Define the basic config
-  config "path" => :string #LogStash::Config::Path
+  dsl_config "path" => :string #LogStash::Config::Path
-  config "tag" => :string #LogStash::Config::Array
+  dsl_config "tag" => :string #LogStash::Config::Array
 
   public
   def initialize(configs, output_queue)

lib/logstash/inputs/file.rb

@@ -4,6 +4,10 @@ require "logstash/namespace"
 require "socket" # for Socket.gethostname
 
 class LogStash::Inputs::File < LogStash::Inputs::Base
+
+  dsl_name "file"
+  #dsl_parent LogStash::Inputs::Base
+
   public
   def initialize(configs, output_queue)
     super