Change the API of wait_any_url to return a tuple of url and response

Previously wait_any_url returned the first url which responded
correctly, but there was no way to actually retrieve its response.

Change-Id: I41aec4fa1f0a5007af70e787a5503ffeb539c783

cloudinit/tests/test_url_helper.py

@@ -29,8 +29,10 @@ class UrlHelperWaitForUrlsTest(test.TestCase):
                                            url, body=b'no worky',
                                            status=400)
 
-        url = url_helper.wait_any_url(urls)
+        url, response = url_helper.wait_any_url(urls)
         self.assertEqual("http://www.yahoo.com", url)
+        self.assertIsInstance(response, url_helper.RequestsResponse)
+        self.assertEqual(response.contents, b'it worked!')
 
     @httpretty.activate
     def test_url_wait_for_no_work(self):

cloudinit/url_helper.py

@@ -226,6 +226,9 @@ def wait_any_url(urls, max_wait=None, timeout=None,
     service but is not going to find one.  It is possible that the instance
     data host (169.254.169.254) may be firewalled off Entirely for a sytem,
     meaning that the connection will block forever unless a timeout is set.
+
+    This will return a tuple of the first url which succeeded and the
+    response object.
     """
     start_time = now()
 
@@ -268,7 +271,7 @@ def wait_any_url(urls, max_wait=None, timeout=None,
                     url_exc = UrlError(ValueError(reason), code=response.code,
                                        headers=response.headers)
                 else:
-                    return url
+                    return url, response
             except UrlError as e:
                 reason = "request error [%s]" % e
                 url_exc = e