Class: Rack::Cors

Inherits:
Object
  • Object
show all
Defined in:
lib/rack/cors.rb,
lib/rack/cors/result.rb,
lib/rack/cors/version.rb,
lib/rack/cors/resource.rb,
lib/rack/cors/resources.rb,
lib/rack/cors/resources/cors_misconfiguration_error.rb

Defined Under Namespace

Classes: Resource, Resources, Result

Constant Summary collapse

HTTP_ORIGIN = 
'HTTP_ORIGIN'
HTTP_X_ORIGIN = 
'HTTP_X_ORIGIN'
HTTP_ACCESS_CONTROL_REQUEST_METHOD = 
'HTTP_ACCESS_CONTROL_REQUEST_METHOD'
HTTP_ACCESS_CONTROL_REQUEST_HEADERS = 
'HTTP_ACCESS_CONTROL_REQUEST_HEADERS'
PATH_INFO = 
'PATH_INFO'
REQUEST_METHOD = 
'REQUEST_METHOD'
RACK_LOGGER = 
'rack.logger'
RACK_CORS = 
ENV_KEY = 'rack.cors'
OPTIONS = 
'OPTIONS'
DEFAULT_VARY_HEADERS = 
['Origin'].freeze
VERSION = 
'2.0.2'

Instance Method Summary collapse

Constructor Details

#initialize(app, opts = {}, &block) ⇒ Cors

Returns a new instance of Cors.



29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
 
# File 'lib/rack/cors.rb', line 29

def initialize(app, opts = {}, &block)
  @app = app
  @debug_mode = !!opts[:debug]
  @logger = @logger_proc = nil

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

  return unless block_given?

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

Instance Method Details

#allow(&block) ⇒ Object 



56
57
58
59
60
61
62
63
64
 
# File 'lib/rack/cors.rb', line 56

def allow(&block)
  all_resources << (resources = Resources.new)

  if block.arity == 1
    block.call(resources)
  else
    resources.instance_eval(&block)
  end
end

#call(env) ⇒ Object 



66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
 
# File 'lib/rack/cors.rb', line 66

def call(env)
  env[HTTP_ORIGIN] ||= env[HTTP_X_ORIGIN] if env[HTTP_X_ORIGIN]

  path = evaluate_path(env)

  add_headers = nil
  if env[HTTP_ORIGIN]
    debug(env) do
      ['Incoming Headers:',
       "  Origin: #{env[HTTP_ORIGIN]}",
       "  Path-Info: #{path}",
       "  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 && env[HTTP_ACCESS_CONTROL_REQUEST_METHOD]
      return [400, {}, []] unless Rack::Utils.valid_path?(path)

      headers = process_preflight(env, path)
      debug(env) do
        "Preflight Headers:\n" +
          headers.collect { |kv| "  #{kv.join(': ')}" }.join("\n")
      end
      return [200, headers, []]
    else
      add_headers = process_cors(env, path)
    end
  else
    Result.miss(env, Result::MISS_NO_ORIGIN)
  end

  # This call must be done BEFORE calling the app because for some reason
  # env[PATH_INFO] gets changed after that and it won't match. (At least
  # in rails 4.1.6)
  vary_resource = resource_for_path(path)

  status, headers, body = @app.call env

  if add_headers
    headers = add_headers.merge(headers)
    debug(env) do
      add_headers.each_pair do |key, value|
        headers["x-rack-cors-original-#{key}"] = value if headers.key?(key)
      end
    end
  end

  # Vary header should ALWAYS mention Origin if there's ANY chance for the
  # response to be different depending on the Origin header value.
  # Better explained here: http://www.fastly.com/blog/best-practices-for-using-the-vary-header/
  if vary_resource
    vary = headers['vary']
    cors_vary_headers = if vary_resource.vary_headers&.any?
                          vary_resource.vary_headers
                        else
                          DEFAULT_VARY_HEADERS
                        end
    headers['vary'] = ((vary ? [vary].flatten.map { |v| v.split(/,\s*/) }.flatten : []) + cors_vary_headers).uniq.join(', ')
  end

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

  [status, headers, body]
end

#debug? ⇒ Boolean

Returns:

  • (Boolean) 


52
53
54
 
# File 'lib/rack/cors.rb', line 52

def debug?
  @debug_mode
end