- Grammar is almost complete.

lib/logstash/config/grammar.rl

@@ -0,0 +1,182 @@
+require "rubygems"
+require "logstash/namespace"
+require "ap" # TODO(sissel): Remove this.
+
+%%{
+  machine logstash_config;
+
+  action mark {
+    @tokenstack.push(p)
+    #puts "Mark: #{self.line(string, p)}##{self.column(string, p)}"
+  }
+
+  action stack_numeric {
+    startpos = @tokenstack.pop
+    endpos = p
+    token = string[startpos ... endpos]
+    #puts "numeric: #{token}"
+    #puts "numeric?: #{string[startpos,50]}"
+    #puts [startpos, endpos].join(",")
+    @stack << token.to_i
+  }
+
+  action stack_string {
+    startpos = @tokenstack.pop
+    endpos = p
+    token = string[startpos ... endpos]
+    #puts "string: #{token}"
+    @stack << token
+  }
+
+  action stack_quoted_string {
+    startpos = @tokenstack.pop
+    endpos = p
+    token = string[startpos + 1 ... endpos - 1] # Skip quotations
+
+    # Parse escapes.
+    token.gsub(/\\./) { |m| return m[1,1] }
+    puts "quotedstring: #{token}"
+    @stack << token
+  }
+
+  action array_init {
+    @array = []
+    @stack << :array_init
+  }
+
+  action array_push {
+    while @stack.last != :array_init
+      @array.unshift @stack.pop
+    end
+    @stack.pop # pop :array_init
+
+    @stack << @array
+    #puts "array: #{@array.join(",")}"
+  }
+
+  action parameter_init {
+    @parameters = Hash.new { |h,k| h[k] = [] }
+  }
+
+  action parameter {
+    value = @stack.pop
+    name = @stack.pop
+    #puts "parameter: #{name} => #{value}"
+    @parameters[name] << value
+  }
+
+  action component_implementation {
+    @components ||= []
+    name = @stack.pop
+    #@components << { :name => name, :parameters => @parameters }
+    @components << { name => @parameters }
+  }
+
+  action component_init {
+    puts "current component: " + @stack.last
+    @components = []
+  }
+
+  action component {
+    name = @stack.pop
+    ap name => @components
+    #ap @stack
+  }
+    
+  ws = ([ \t\n])** ;
+  quoted_string = ( ( "\"" ( ( (any - [\\"\n]) | "\\" any )* ) "\"" ) |
+                    ( "'" ( ( (any - [\\'\n]) | "\\" any )* ) "'" ) )
+                  >mark %stack_quoted_string ;
+
+  # TODO(sissel): Support floating point values?
+  numeric = ( ("+" | "-")?  [0-9] [0-9]** ) >mark %stack_numeric;
+  naked_string = ( [A-Za-z_] [A-Za-z0-9_]** ) >mark %stack_string ;
+  string = ( quoted_string | naked_string ) ;
+
+  array = ( "[" ws string ws ("," ws string ws)* "]" ) >array_init %array_push;
+  parameter_value = ( numeric | string | array );
+  parameter = ( string ws "=>" ws parameter_value ) %parameter ;
+  parameters = ( parameter ( ws parameter )** ) >parameter_init ;
+
+  # Statement:
+  # component {
+  #   component_implementation_name {
+  #     bar => ...
+  #     baz => ...
+  #   }
+  #   ...
+  # }
+
+  component_implementation = (
+    naked_string ws "{" ws
+      parameters
+    ws "}"
+  ) %component_implementation ; 
+
+  component = (
+    naked_string ws "{"
+      >component_init
+      ( ws component_implementation )**
+    ws "}"
+  ) %component ;
+
+  statement = (ws component )* ;
+
+  main := statement
+          0 @{ puts "Failed" }
+          $err { 
+            # Compute line and column of the cursor (p)
+            puts "Error at line #{self.line(string, p)}, column #{self.column(string, p)}: #{string[p .. -1].inspect}"
+          } ;
+}%%
+
+class LogStash::Config::Parser
+  attr_accessor :eof
+
+  def initialize
+    # BEGIN RAGEL DATA
+    %% write data;
+    # END RAGEL DATA
+
+    @tokenstack = Array.new
+    @stack = Array.new
+
+    @types = Hash.new { |h,k| h[k] = [] }
+    @edges = []
+  end
+
+  def parse(string)
+    data = string.unpack("c*")
+
+    # BEGIN RAGEL INIT
+    %% write init;
+    # END RAGEL INIT
+
+    begin 
+      # BEGIN RAGEL EXEC 
+      %% write exec;
+      # END RAGEL EXEC
+    rescue => e
+      # Compute line and column of the cursor (p)
+      $stderr.puts "Exception at line #{self.line(string, p)}, column #{self.column(string, p)}: #{string[p .. -1].inspect}"
+      raise e
+    end
+
+    return cs
+  end
+
+  def line(str, pos)
+    return str[0 .. pos].count("\n") + 1
+  end
+
+  def column(str, pos)
+    return str[0 .. pos].split("\n").last.length
+  end
+
+end # class LogStash::Config::Parser
+
+def parse(string)
+  puts "result %s" % LogStash::Config::Parser.new.parse(string)
+end
+
+parse(File.open(ARGV[0]).read)

lib/logstash/config/test.conf

@@ -0,0 +1,18 @@
+inputs {
+  amqp {
+    port => 12345
+    tag => [ a, b, c ]
+  }
+
+  stomp {
+    port => 12345
+    tag => [ stomp ]
+  }
+}
+
+filters {
+  date { 
+    hello => "Hello"
+    hello => "Hello"
+  }
+}