Testing RESTful web services using PHPUnit

Abstract the Request into a Request Object. This way you can test your code without actually having to make real Requests. Testing that is easy then.

class RequestTest extends PHPUnit_Framework_TestCase
{
    public function testRequest()
    {
        $request = new Request();
        $request->setMethod('PUT');
        $request->setPutData(…);
        $this->assertSomething(
            $this->testSubjectUsingRequest->process($request)
        );
    }
}

In case you want to test the responses from a Webservice, mock/stub the API of the Webservice.

There is a chapter in the PHPUnit chapter about Stubbing and Mocking Web Services although the suggested in-built webservice mocking facilities apply to Soap Services with WSDL, so you'd have to configure your Mocks by hand (just as you would with any mocked resource).

If this doesn't answer your question please update your question with more details about the RESTful service what you are trying to do/test with it.