One thing that has always been a pain with remote web services is testing. The HttpMock class makes it easy to test your Active Resource models by creating a set of mock responses to specific requests.

To test your Active Resource model, you simply call the ActiveResource::HttpMock.respond_to method with an attached block. The block declares a set of URIs with expected input, and the output each request should return. The passed in block has any number of entries in the following generalized format:

  mock.http_method(path, request_headers = {}, body = nil, status = 200, response_headers = {})
  • http_method - The HTTP method to listen for. This can be get, post, put, delete or head.
  • path - A string, starting with a "/", defining the URI that is expected to be called.
  • request_headers - Headers that are expected along with the request. This argument uses a hash format, such as { "Content-Type" => "application/xml" }. This mock will only trigger if your tests sends a request with identical headers.
  • body - The data to be returned. This should be a string of Active Resource parseable content, such as XML.
  • status - The HTTP response code, as an integer, to return with the response.
  • response_headers - Headers to be returned with the response. Uses the same hash format as request_headers listed above.

In order for a mock to deliver its content, the incoming request must match by the http_method, path and request_headers. If no match is found an InvalidRequestError exception will be raised showing you what request it could not find a response for and also what requests and response pairs have been recorded so you can create a new mock for that request.

Example

  def setup
    @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")
    ActiveResource::HttpMock.respond_to do |mock|
      mock.post   "/people.xml",   {}, @matz, 201, "Location" => "/people/1.xml"
      mock.get    "/people/1.xml", {}, @matz
      mock.put    "/people/1.xml", {}, nil, 204
      mock.delete "/people/1.xml", {}, nil, 200
    end
  end

  def test_get_matz
    person = Person.find(1)
    assert_equal "Matz", person.name
  end
Methods
Public Class methods
requests()

Returns an array of all request objects that have been sent to the mock. You can use this to check if your model actually sent an HTTP request.

Example

  def setup
    @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")
    ActiveResource::HttpMock.respond_to do |mock|
      mock.get "/people/1.xml", {}, @matz
    end
  end

  def test_should_request_remote_service
    person = Person.find(1)  # Call the remote service

    # This request object has the same HTTP method and path as declared by the mock
    expected_request = ActiveResource::Request.new(:get, "/people/1.xml")

    # Assert that the mock received, and responded to, the expected request from the model
    assert ActiveResource::HttpMock.requests.include?(expected_request)
  end
    # File activeresource/lib/active_resource/http_mock.rb, line 92
92:       def requests
93:         @@requests ||= []
94:       end
reset!()

Deletes all logged requests and responses.

     # File activeresource/lib/active_resource/http_mock.rb, line 184
184:       def reset!
185:         requests.clear
186:         responses.clear
187:       end
respond_to(*args) {|mock| ...}

Accepts a block which declares a set of requests and responses for the HttpMock to respond to in the following format:

  mock.http_method(path, request_headers = {}, body = nil, status = 200, response_headers = {})

Example

  @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")
  ActiveResource::HttpMock.respond_to do |mock|
    mock.post   "/people.xml",   {}, @matz, 201, "Location" => "/people/1.xml"
    mock.get    "/people/1.xml", {}, @matz
    mock.put    "/people/1.xml", {}, nil, 204
    mock.delete "/people/1.xml", {}, nil, 200
  end

Alternatively, accepts a hash of {Request => Response} pairs allowing you to generate these the following format:

  ActiveResource::Request.new(method, path, body, request_headers)
  ActiveResource::Response.new(body, status, response_headers)

Example

Request.new(:#{method}, path, nil, request_headers)

  @matz  = { :id => 1, :name => "Matz" }.to_xml(:root => "person")

  create_matz      = ActiveResource::Request.new(:post, '/people.xml', @matz, {})
  created_response = ActiveResource::Response.new("", 201, {"Location" => "/people/1.xml"})
  get_matz         = ActiveResource::Request.new(:get, '/people/1.xml', nil)
  ok_response      = ActiveResource::Response.new("", 200, {})

  pairs = {create_matz => created_response, get_matz => ok_response}

  ActiveResource::HttpMock.respond_to(pairs)

Note, by default, every time you call respond_to, any previous request and response pairs stored in HttpMock will be deleted giving you a clean slate to work on.

If you want to override this behaviour, pass in false as the last argument to respond_to

Example

  ActiveResource::HttpMock.respond_to do |mock|
    mock.send(:get, "/people/1", {}, "XML1")
  end
  ActiveResource::HttpMock.responses.length #=> 1

  ActiveResource::HttpMock.respond_to(false) do |mock|
    mock.send(:get, "/people/2", {}, "XML2")
  end
  ActiveResource::HttpMock.responses.length #=> 2

This also works with passing in generated pairs of requests and responses, again, just pass in false as the last argument:

Example

  ActiveResource::HttpMock.respond_to do |mock|
    mock.send(:get, "/people/1", {}, "XML1")
  end
  ActiveResource::HttpMock.responses.length #=> 1

  get_matz         = ActiveResource::Request.new(:get, '/people/1.xml', nil)
  ok_response      = ActiveResource::Response.new("", 200, {})

  pairs = {get_matz => ok_response}

  ActiveResource::HttpMock.respond_to(pairs, false)
  ActiveResource::HttpMock.responses.length #=> 2
     # File activeresource/lib/active_resource/http_mock.rb, line 172
172:       def respond_to(*args) #:yields: mock
173:         pairs = args.first || {}
174:         reset! if args.last.class != FalseClass
175:         responses.concat pairs.to_a
176:         if block_given?
177:           yield Responder.new(responses)
178:         else
179:           Responder.new(responses)
180:         end
181:       end
responses()

Returns the list of requests and their mocked responses. Look up a response for a request using responses.assoc(request).

     # File activeresource/lib/active_resource/http_mock.rb, line 98
 98:       def responses
 99:         @@responses ||= []
100:       end