.gitignore

*.c
*.rl

README.markdown

Journey Routing Table => Ragel PoC

Run this to generate and compile your routes:

$ rake

Run the tests (after compile):

$ ruby -I. test.rb

TODO

• Need to add support for regexps.

• The current implementation translates the AST directly to ragel, should we generate a GTG first so the table is more compact?

extconf.rb

require 'mkmf'

# :stopdoc:

create_makefile 'router'

# :startdoc:

Rakefile

task :clean do
  rm_f 'router.c'
  rm_f 'router.rl'
  rm_f 'router.o'
  rm_f 'Makefile'
  rm_f 'router.bundle'
  rm_f 'router.so'
end

task :default do
  ruby 'route_compiler.rb > router.rl'
  sh 'ragel router.rl'
  ruby 'extconf.rb'
  sh 'make'
end

route_compiler.rb

require 'journey'

def asts paths
  parser  = Journey::Parser.new
  Journey::Nodes::Or.new paths.map { |x| parser.parse x }
end

class Ragel < Journey::Visitors::Visitor
  def terminal(n)
    n.left.inspect
  end

  def visit_OR(n)
    "(#{n.children.map { |x| visit x }.join ' | '})"
  end

  def visit_GROUP(n)
    "(#{visit n})"
  end

  def visit_CAT(n)
    "#{visit n.left} . #{visit n.right}"
  end
end

## These come from your routes.rb
ast = asts %w{
  /articles
  /articles/new
}

ragel = Ragel.new.accept ast

data = <<-eoc
#include <ruby.h>

%%{
machine router;

action match { ret = Qtrue; }

main := #{ragel} %match;

}%%

%% write data;

static VALUE match(VALUE self, VALUE string)
{
  int cs = 0;
  char *p = RSTRING_PTR(string);
  char *pe = p + RSTRING_LEN(string);
  char *eof = pe;

  VALUE ret = Qfalse;

  %% write init;
  %% write exec;

  return ret;
}

void Init_router()
{
    VALUE mRouter = rb_define_class("Router", rb_cObject);
    rb_define_method(mRouter, "match", match, 1);
}
eoc

puts data

test.rb

# ruby -I. test.rb
require 'router'
require 'minitest/autorun'

class RouterTest < MiniTest::Unit::TestCase
  def setup
    @router = Router.new
  end

  def test_omg
    assert @router.match '/articles/new'
    refute @router.match '/articles/nw'
    assert @router.match '/articles'
  end
end