diff --git a/.coveragerc b/.coveragerc
index f4c5b83f..f0624d2e 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,7 +1,7 @@
 [run]
 branch = True
-source = sanic, tests
-omit = site-packages
+source = sanic
+omit = site-packages, sanic/utils.py
 
 [html]
-directory = coverage
\ No newline at end of file
+directory = coverage
diff --git a/docs/sanic/extensions.md b/docs/sanic/extensions.md
index fe0f223a..efd25d2c 100644
--- a/docs/sanic/extensions.md
+++ b/docs/sanic/extensions.md
@@ -11,3 +11,4 @@ A list of Sanic extensions created by the community.
 - [Pagination](https://github.com/lixxu/python-paginate): Simple pagination support.
 - [Motor](https://github.com/lixxu/sanic-motor): Simple motor wrapper.
 - [Sanic CRUD](https://github.com/Typhon66/sanic_crud): CRUD REST API generation with peewee models.
+- [UserAgent](https://github.com/lixxu/sanic-useragent): Add `user_agent` to request
diff --git a/sanic/server.py b/sanic/server.py
index 99652fc9..83bda3fc 100644
--- a/sanic/server.py
+++ b/sanic/server.py
@@ -167,19 +167,26 @@ class HttpProtocol(asyncio.Protocol):
     # -------------------------------------------- #
 
     def write_response(self, response):
+        keep_alive = (
+            self.parser.should_keep_alive() and not self.signal.stopped)
         try:
-            keep_alive = (
-                self.parser.should_keep_alive() and not self.signal.stopped)
             self.transport.write(
                 response.output(
                     self.request.version, keep_alive, self.request_timeout))
+        except AttributeError:
+            log.error(
+                ('Invalid response object for url {}, '
+                 'Expected Type: HTTPResponse, Actual Type: {}').format(
+                    self.url, type(response)))
+            self.write_error(ServerError('Invalid response type'))
         except RuntimeError:
             log.error(
                 'Connection lost before response written @ {}'.format(
                     self.request.ip))
         except Exception as e:
             self.bail_out(
-                "Writing response failed, connection closed {}".format(e))
+                "Writing response failed, connection closed {}".format(
+                    repr(e)))
         finally:
             if not keep_alive:
                 self.transport.close()
@@ -196,10 +203,10 @@ class HttpProtocol(asyncio.Protocol):
         except RuntimeError:
             log.error(
                 'Connection lost before error written @ {}'.format(
-                    self.request.ip))
+                    self.request.ip if self.request else 'Unknown'))
         except Exception as e:
             self.bail_out(
-                "Writing error failed, connection closed {}".format(e),
+                "Writing error failed, connection closed {}".format(repr(e)),
                 from_error=True)
         finally:
             self.transport.close()
diff --git a/tox.ini b/tox.ini
index 4155e909..05276a43 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,10 +14,13 @@ deps =
     aiohttp
     pytest
     beautifulsoup4
+    coverage
 
 commands =
     pytest tests {posargs}
-
+    coverage erase
+    coverage run -m sanic.app
+    coverage report
 
 [testenv:flake8]
 deps =