class Rack::Cors

Constants

VERSION

Public Class Methods

new(app, opts={}, &block) click to toggle source
# File lib/rack/cors.rb, line 5
def initialize(app, opts={}, &block)
  @app = app
  @logger = opts[:logger]
  @debug_mode = !!opts[:debug]

  if block_given?
    if block.arity == 1
      block.call(self)
    else
      instance_eval(&block)
    end
  end
end

Public Instance Methods

allow(&block) click to toggle source
# File lib/rack/cors.rb, line 19
def allow(&block)
  all_resources << (resources = Resources.new)

  if block.arity == 1
    block.call(resources)
  else
    resources.instance_eval(&block)
  end
end
call(env) click to toggle source
# File lib/rack/cors.rb, line 29
def call(env)
  env['HTTP_ORIGIN'] = 'file://' if env['HTTP_ORIGIN'] == 'null'
  env['HTTP_ORIGIN'] ||= env['HTTP_X_ORIGIN']

  cors_headers = nil
  if env['HTTP_ORIGIN']
    debug(env) do
      [ 'Incoming Headers:',
        "  Origin: #{env['HTTP_ORIGIN']}",
        "  Access-Control-Request-Method: #{env['HTTP_ACCESS_CONTROL_REQUEST_METHOD']}",
        "  Access-Control-Request-Headers: #{env['HTTP_ACCESS_CONTROL_REQUEST_HEADERS']}"
        ].join("\n")
    end
    if env['REQUEST_METHOD'] == 'OPTIONS' and env['HTTP_ACCESS_CONTROL_REQUEST_METHOD']
      if headers = process_preflight(env)
        debug(env) do
          "Preflight Headers:\n" +
              headers.collect{|kv| "  #{kv.join(': ')}"}.join("\n")
        end
        return [200, headers, []]
      end
    else
      cors_headers = process_cors(env)
    end
  end
  status, headers, body = @app.call env
  if cors_headers
    headers = headers.merge(cors_headers)

    # http://www.w3.org/TR/cors/#resource-implementation
    unless headers['Access-Control-Allow-Origin'] == '*'
      vary = headers['Vary']
      headers['Vary'] = ((vary ? vary.split(/,\s*/) : []) + ['Origin']).uniq.join(', ')
    end
  end
  [status, headers, body]
end

Protected Instance Methods

all_resources() click to toggle source
# File lib/rack/cors.rb, line 77
def all_resources
  @all_resources ||= []
end
debug(env, message = nil, &block) click to toggle source
# File lib/rack/cors.rb, line 68
def debug(env, message = nil, &block)
  if @debug_mode
    logger = @logger || env['rack.logger'] || begin
      @logger = ::Logger.new(STDOUT).tap {|logger| logger.level = ::Logger::Severity::INFO}
    end
    logger.debug(message, &block)
  end
end
find_resource(origin, path, env) click to toggle source
# File lib/rack/cors.rb, line 91
def find_resource(origin, path, env)
  all_resources.each do |r|
    if r.allow_origin?(origin, env) and found = r.find_resource(path)
      return found
    end
  end
  nil
end
process_cors(env) click to toggle source
# File lib/rack/cors.rb, line 86
def process_cors(env)
  resource = find_resource(env['HTTP_ORIGIN'], env['PATH_INFO'],env)
  resource.to_headers(env) if resource
end
process_preflight(env) click to toggle source
# File lib/rack/cors.rb, line 81
def process_preflight(env)
  resource = find_resource(env['HTTP_ORIGIN'], env['PATH_INFO'],env)
  resource && resource.process_preflight(env)
end