Tornado support

vcr/patch.py

@@ -52,6 +52,25 @@ else:
     _CertValidatingHTTPSConnection = boto.https_connection.CertValidatingHTTPSConnection
 
 
+# Try to save the original types for Tornado
+try:
+    import tornado.httpclient
+    import tornado.simple_httpclient
+except ImportError:  # pragma: no cover
+    pass
+else:
+    _AsyncHTTPClient = tornado.httpclient.AsyncHTTPClient
+    _SimpleAsyncHTTPClient = tornado.simple_httpclient.SimpleAsyncHTTPClient
+
+
+try:
+    import tornado.curl_httpclient
+except ImportError:  # pragma: no cover
+    pass
+else:
+    _CurlAsyncHTTPClient = tornado.curl_httpclient.CurlAsyncHTTPClient
+
+
 class CassettePatcherBuilder(object):
 
     def _build_patchers_from_mock_triples_decorator(function):
@@ -68,10 +87,11 @@ class CassettePatcherBuilder(object):
 
     def build(self):
         return itertools.chain(
-            self._httplib(), self._requests(), self._urllib3(), self._httplib2(),
-            self._boto(), self._build_patchers_from_mock_triples(
+            self._httplib(), self._requests(), self._urllib3(),
+            self._httplib2(), self._boto(), self._tornado(),
+            self._build_patchers_from_mock_triples(
                 self._cassette.custom_patches
-            )
+            ),
         )
 
     def _build_patchers_from_mock_triples(self, mock_triples):
@@ -205,6 +225,27 @@ class CassettePatcherBuilder(object):
             from .stubs.boto_stubs import VCRCertValidatingHTTPSConnection
             yield cpool, 'CertValidatingHTTPSConnection', VCRCertValidatingHTTPSConnection
 
+    @_build_patchers_from_mock_triples_decorator
+    def _tornado(self):
+        try:
+            import tornado.httpclient as http
+            import tornado.simple_httpclient as simple
+        except ImportError:  # pragma: no cover
+            pass
+        else:
+            from .stubs.tornado_stubs import VCRAsyncHTTPClient
+            from .stubs.tornado_stubs import VCRSimpleAsyncHTTPClient
+
+            yield http, 'AsyncHTTPClient', VCRAsyncHTTPClient
+            yield simple, 'SimpleAsyncHTTPClient', VCRSimpleAsyncHTTPClient
+        try:
+            import tornado.curl_httpclient as curl
+        except ImportError:  # pragma: no cover
+            pass
+        else:
+            from .stubs.tornado_stubs import VCRCurlAsyncHTTPClient
+            yield curl, 'CurlAsyncHTTPClient', VCRCurlAsyncHTTPClient
+
     def _urllib3_patchers(self, cpool, stubs):
         http_connection_remover = ConnectionRemover(
             self._get_cassette_subclass(stubs.VCRRequestsHTTPConnection)
@@ -320,6 +361,21 @@ def reset_patchers():
         yield mock.patch.object(cpool, 'CertValidatingHTTPSConnection',
                                 _CertValidatingHTTPSConnection)
 
+    try:
+        import tornado.httpclient as http
+        import tornado.simple_httpclient as simple
+    except ImportError:  # pragma: no cover
+        pass
+    else:
+        yield mock.patch.object(http, 'AsyncHTTPClient', _AsyncHTTPClient)
+        yield mock.patch.object(simple, 'SimpleAsyncHTTPClient', _SimpleAsyncHTTPClient)
+    try:
+        import tornado.curl_httpclient as curl
+    except ImportError:  # pragma: no cover
+        pass
+    else:
+        yield mock.patch.object(curl, 'CurlAsyncHTTPClient', _CurlAsyncHTTPClient)
+
 
 @contextlib.contextmanager
 def force_reset():

vcr/stubs/tornado_stubs.py

@@ -0,0 +1,147 @@
+'''Stubs for tornado HTTP clients'''
+from __future__ import absolute_import
+
+from six import BytesIO
+
+from tornado import httputil
+from tornado.httpclient import AsyncHTTPClient
+from tornado.httpclient import HTTPResponse
+from tornado.simple_httpclient import SimpleAsyncHTTPClient
+
+from vcr.errors import CannotOverwriteExistingCassetteException
+from vcr.request import Request
+
+
+class _VCRAsyncClient(object):
+    cassette = None
+
+    def __new__(cls, *args, **kwargs):
+        from vcr.patch import force_reset
+        with force_reset():
+            return super(_VCRAsyncClient, cls).__new__(cls, *args, **kwargs)
+
+    def initialize(self, *args, **kwargs):
+        from vcr.patch import force_reset
+        with force_reset():
+            self.real_client = self._baseclass(*args, **kwargs)
+
+    @property
+    def io_loop(self):
+        return self.real_client.io_loop
+
+    @property
+    def _closed(self):
+        return self.real_client._closed
+
+    @property
+    def defaults(self):
+        return self.real_client.defaults
+
+    def close(self):
+        from vcr.patch import force_reset
+        with force_reset():
+            self.real_client.close()
+
+    def fetch_impl(self, request, callback):
+        headers = dict(request.headers)
+        if request.user_agent:
+            headers.setdefault('User-Agent', request.user_agent)
+
+        # TODO body_producer, header_callback, and streaming_callback are not
+        # yet supported.
+
+        unsupported_call = (
+            request.body_producer is not None or
+            request.header_callback is not None or
+            request.streaming_callback is not None
+        )
+        if unsupported_call:
+            response = HTTPResponse(
+                request,
+                599,
+                error=Exception(
+                    "The request (%s) uses AsyncHTTPClient functionality "
+                    "that is not yet supported by VCR.py. Please make the "
+                    "request outside a VCR.py context." % repr(request)
+                ),
+            )
+
+        vcr_request = Request(
+            request.method,
+            request.url,
+            request.body,
+            headers,
+        )
+
+        if self.cassette.can_play_response_for(vcr_request):
+            vcr_response = self.cassette.play_response(vcr_request)
+            headers = httputil.HTTPHeaders()
+
+            recorded_headers = vcr_response['headers']
+            if isinstance(recorded_headers, dict):
+                recorded_headers = recorded_headers.items()
+            for k, vs in recorded_headers:
+                for v in vs:
+                    headers.add(k, v)
+            response = HTTPResponse(
+                request,
+                code=vcr_response['status']['code'],
+                reason=vcr_response['status']['message'],
+                headers=headers,
+                buffer=BytesIO(vcr_response['body']['string']),
+            )
+            callback(response)
+        else:
+            if self.cassette.write_protected and self.cassette.filter_request(
+                vcr_request
+            ):
+                response = HTTPResponse(
+                    request,
+                    599,
+                    error=CannotOverwriteExistingCassetteException(
+                        "No match for the request (%r) was found. "
+                        "Can't overwrite existing cassette (%r) in "
+                        "your current record mode (%r)."
+                        % (vcr_request, self.cassette._path,
+                           self.cassette.record_mode)
+                    ),
+                )
+                callback(response)
+
+            def new_callback(response):
+                headers = [
+                    (k, response.headers.get_list(k))
+                    for k in response.headers.keys()
+                ]
+
+                vcr_response = {
+                    'status': {
+                        'code': response.code,
+                        'message': response.reason,
+                    },
+                    'headers': headers,
+                    'body': {'string': response.body},
+                }
+                self.cassette.append(vcr_request, vcr_response)
+                callback(response)
+
+            from vcr.patch import force_reset
+            with force_reset():
+                self.real_client.fetch_impl(request, new_callback)
+
+
+class VCRAsyncHTTPClient(_VCRAsyncClient, AsyncHTTPClient):
+    _baseclass = AsyncHTTPClient
+
+
+class VCRSimpleAsyncHTTPClient(_VCRAsyncClient, SimpleAsyncHTTPClient):
+    _baseclass = SimpleAsyncHTTPClient
+
+
+try:
+    from tornado.curl_httpclient import CurlAsyncHTTPClient
+except ImportError:  # pragma: no cover
+    VCRCurlAsyncHTTPClient = None
+else:
+    class VCRCurlAsyncHTTPClient(_VCRAsyncClient, CurlAsyncHTTPClient):
+        _baseclass = CurlAsyncHTTPClient