vendor/rails/activeresource/lib/active_resource/http_mock.rb

   1 require 'active_resource/connection'
   2
   3 module ActiveResource
   4   class InvalidRequestError < StandardError; end #:nodoc:
   5
   6   # One thing that has always been a pain with remote web services is testing.  The HttpMock
   7   # class makes it easy to test your Active Resource models by creating a set of mock responses to specific
   8   # requests.
   9   #
  10   # To test your Active Resource model, you simply call the ActiveResource::HttpMock.respond_to
  11   # method with an attached block.  The block declares a set of URIs with expected input, and the output
  12   # each request should return.  The passed in block has any number of entries in the following generalized
  13   # format:
  14   #
  15   #   mock.http_method(path, request_headers = {}, body = nil, status = 200, response_headers = {})
  16   #
  17   # * <tt>http_method</tt> - The HTTP method to listen for.  This can be +get+, +post+, +put+, +delete+ or
  18   #   +head+.
  19   # * <tt>path</tt> - A string, starting with a "/", defining the URI that is expected to be
  20   #   called.
  21   # * <tt>request_headers</tt> - Headers that are expected along with the request.  This argument uses a
  22   #   hash format, such as <tt>{ "Content-Type" => "application/xml" }</tt>.  This mock will only trigger
  23   #   if your tests sends a request with identical headers.
  24   # * <tt>body</tt> - The data to be returned.  This should be a string of Active Resource parseable content,
  25   #   such as XML.
  26   # * <tt>status</tt> - The HTTP response code, as an integer, to return with the response.
  27   # * <tt>response_headers</tt> - Headers to be returned with the response.  Uses the same hash format as
  28   #   <tt>request_headers</tt> listed above.
  29   #
  30   # In order for a mock to deliver its content, the incoming request must match by the <tt>http_method</tt>,
  31   # +path+ and <tt>request_headers</tt>.  If no match is found an InvalidRequestError exception
  32   # will be raised letting you know you need to create a new mock for that request.
  33   #
  34   # ==== Example
  35   #   def setup
  36   #     @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")
  37   #     ActiveResource::HttpMock.respond_to do |mock|
  38   #       mock.post   "/people.xml",   {}, @matz, 201, "Location" => "/people/1.xml"
  39   #       mock.get    "/people/1.xml", {}, @matz
  40   #       mock.put    "/people/1.xml", {}, nil, 204
  41   #       mock.delete "/people/1.xml", {}, nil, 200
  42   #     end
  43   #   end
  44   #
  45   #   def test_get_matz
  46   #     person = Person.find(1)
  47   #     assert_equal "Matz", person.name
  48   #   end
  49   #
  50   class HttpMock
  51     class Responder #:nodoc:
  52       def initialize(responses)
  53         @responses = responses
  54       end
  55
  56       for method in [ :post, :put, :get, :delete, :head ]
  57         module_eval <<-EOE, __FILE__, __LINE__
  58           def #{method}(path, request_headers = {}, body = nil, status = 200, response_headers = {})
  59             @responses[Request.new(:#{method}, path, nil, request_headers)] = Response.new(body || "", status, response_headers)
  60           end
  61         EOE
  62       end
  63     end
  64
  65     class << self
  66
  67       # Returns an array of all request objects that have been sent to the mock.  You can use this to check
  68       # if your model actually sent an HTTP request.
  69       #
  70       # ==== Example
  71       #   def setup
  72       #     @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")
  73       #     ActiveResource::HttpMock.respond_to do |mock|
  74       #       mock.get "/people/1.xml", {}, @matz
  75       #     end
  76       #   end
  77       #
  78       #   def test_should_request_remote_service
  79       #     person = Person.find(1)  # Call the remote service
  80       #
  81       #     # This request object has the same HTTP method and path as declared by the mock
  82       #     expected_request = ActiveResource::Request.new(:get, "/people/1.xml")
  83       #
  84       #     # Assert that the mock received, and responded to, the expected request from the model
  85       #     assert ActiveResource::HttpMock.requests.include?(expected_request)
  86       #   end
  87       def requests
  88         @@requests ||= []
  89       end
  90
  91       # Returns a hash of <tt>request => response</tt> pairs for all all responses this mock has delivered, where +request+
  92       # is an instance of ActiveResource::Request and the response is, naturally, an instance of
  93       # ActiveResource::Response.
  94       def responses
  95         @@responses ||= {}
  96       end
  97
  98       # Accepts a block which declares a set of requests and responses for the HttpMock to respond to. See the main
  99       # ActiveResource::HttpMock description for a more detailed explanation.
 100       def respond_to(pairs = {}) #:yields: mock
 101         reset!
 102         pairs.each do |(path, response)|
 103           responses[path] = response
 104         end
 105
 106         if block_given?
 107           yield Responder.new(responses)
 108         else
 109           Responder.new(responses)
 110         end
 111       end
 112
 113       # Deletes all logged requests and responses.
 114       def reset!
 115         requests.clear
 116         responses.clear
 117       end
 118     end
 119
 120     for method in [ :post, :put ]
 121       module_eval <<-EOE, __FILE__, __LINE__
 122         def #{method}(path, body, headers)
 123           request = ActiveResource::Request.new(:#{method}, path, body, headers)
 124           self.class.requests << request
 125           self.class.responses[request] || raise(InvalidRequestError.new("No response recorded for \#{request}"))
 126         end
 127       EOE
 128     end
 129
 130     for method in [ :get, :delete, :head ]
 131       module_eval <<-EOE, __FILE__, __LINE__
 132         def #{method}(path, headers)
 133           request = ActiveResource::Request.new(:#{method}, path, nil, headers)
 134           self.class.requests << request
 135           self.class.responses[request] || raise(InvalidRequestError.new("No response recorded for \#{request}"))
 136         end
 137       EOE
 138     end
 139
 140     def initialize(site) #:nodoc:
 141       @site = site
 142     end
 143   end
 144
 145   class Request
 146     attr_accessor :path, :method, :body, :headers
 147
 148     def initialize(method, path, body = nil, headers = {})
 149       @method, @path, @body, @headers = method, path, body, headers.merge(ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[method] => 'application/xml')
 150     end
 151
 152     def ==(other_request)
 153       other_request.hash == hash
 154     end
 155
 156     def eql?(other_request)
 157       self == other_request
 158     end
 159
 160     def to_s
 161       "<#{method.to_s.upcase}: #{path} [#{headers}] (#{body})>"
 162     end
 163
 164     def hash
 165       "#{path}#{method}#{headers}".hash
 166     end
 167   end
 168
 169   class Response
 170     attr_accessor :body, :message, :code, :headers
 171
 172     def initialize(body, message = 200, headers = {})
 173       @body, @message, @headers = body, message.to_s, headers
 174       @code = @message[0,3].to_i
 175
 176       resp_cls = Net::HTTPResponse::CODE_TO_OBJ[@code.to_s]
 177       if resp_cls && !resp_cls.body_permitted?
 178         @body = nil
 179       end
 180
 181       if @body.nil?
 182         self['Content-Length'] = "0"
 183       else
 184         self['Content-Length'] = body.size.to_s
 185       end
 186     end
 187
 188     def success?
 189       (200..299).include?(code)
 190     end
 191
 192     def [](key)
 193       headers[key]
 194     end
 195
 196     def []=(key, value)
 197       headers[key] = value
 198     end
 199
 200     def ==(other)
 201       if (other.is_a?(Response))
 202         other.body == body && other.message == message && other.headers == headers
 203       else
 204         false
 205       end
 206     end
 207   end
 208
 209   class Connection
 210     private
 211       silence_warnings do
 212         def http
 213           @http ||= HttpMock.new(@site)
 214         end
 215       end
 216   end
 217 end