class Rack::Cors

Constants

ENV_KEY
ORIGIN_HEADER_KEY
PATH_INFO_HEADER_KEY
VERSION

Public Class Methods

new(app, opts={}, &block) click to toggle source
# File lib/rack/cors.rb, line 10
def initialize(app, opts={}, &block)
  @app = app
  @debug_mode = !!opts[:debug]

  if logger = opts[:logger]
    if logger.respond_to? :call
      @logger_proc = opts[:logger]
    else
      @logger = logger
    end
  end

  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 35
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 45
def call(env)
  env[ORIGIN_HEADER_KEY] ||= env['HTTP_X_ORIGIN']

  add_headers = nil
  if env[ORIGIN_HEADER_KEY]
    debug(env) do
      [ 'Incoming Headers:',
        "  Origin: #{env[ORIGIN_HEADER_KEY]}",
        "  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
      add_headers = process_cors(env)
    end
  else
    Result.miss(env, Result::MISS_NO_ORIGIN)
  end

  status, headers, body = @app.call env

  if add_headers
    headers = headers.merge(add_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

  if debug? && result = env[ENV_KEY]
    result.append_header(headers)
  end

  [status, headers, body]
end
debug?() click to toggle source
# File lib/rack/cors.rb, line 31
def debug?
  @debug_mode
end

Protected Instance Methods

all_resources() click to toggle source
# File lib/rack/cors.rb, line 113
def all_resources
  @all_resources ||= []
end
debug(env, message = nil, &block) click to toggle source
# File lib/rack/cors.rb, line 92
def debug(env, message = nil, &block)
  (@logger || select_logger(env)).debug(message, &block) if debug?
end
find_resource(env) click to toggle source
# File lib/rack/cors.rb, line 143
def find_resource(env)
  path   = env[PATH_INFO_HEADER_KEY]
  origin = env[ORIGIN_HEADER_KEY]

  origin_matched = false
  all_resources.each do |r|
    if r.allow_origin?(origin, env)
      origin_matched = true
      if found = r.find_resource(path)
        return [found, nil]
      end
    end
  end

  [nil, origin_matched ? Result::MISS_NO_PATH : Result::MISS_NO_ORIGIN]
end
process_cors(env) click to toggle source
# File lib/rack/cors.rb, line 130
def process_cors(env)
  resource, error = find_resource(env)
  if resource
    Result.hit(env)
    cors = resource.to_headers(env)
    cors

  else
    Result.miss(env, error)
    nil
  end
end
process_preflight(env) click to toggle source
# File lib/rack/cors.rb, line 117
def process_preflight(env)
  resource, error = find_resource(env)
  if resource
    Result.preflight_hit(env)
    preflight = resource.process_preflight(env)
    preflight

  else
    Result.preflight_miss(env, error)
    nil
  end
end
select_logger(env) click to toggle source
# File lib/rack/cors.rb, line 96
def select_logger(env)
  @logger = if @logger_proc
    logger_proc = @logger_proc
    @logger_proc = nil
    logger_proc.call

  elsif defined?(Rails) && Rails.logger
    Rails.logger

  elsif env['rack.logger']
    env['rack.logger']

  else
    ::Logger.new(STDOUT).tap { |logger| logger.level = ::Logger::Severity::DEBUG }
  end
end