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 ::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_headerslisted above.

In order for a mock to deliver its content, the incoming request must match by the http_method, pathand 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
R
Class Public 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 91
def requests
  @@requests ||= []
end
reset!()

Deletes all logged requests and responses.

# File activeresource/lib/active_resource/http_mock.rb, line 183
def reset!
  requests.clear
  responses.clear
end
respond_to(*args)

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

ActiveResource::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 falseas 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 171
def respond_to(*args) #:yields: mock
  pairs = args.first || {}
  reset! if args.last.class != FalseClass
  responses.concat pairs.to_a
  if block_given?
    yield Responder.new(responses)
  else
    Responder.new(responses)
  end
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 97
def responses
  @@responses ||= []
end