Fix #976: Add support for websocket send_json and receive_json (#984)

* Fix #976: Add support for websocket send_json and receive_json

* Fix for (#976): use send_str instead of low level send method

* Fix for (#976): add test for websocket send_json and receive_json

* Fix for (#976): refactor websocket send_json and receive_json

* Fix for (#976): refactor tests for websocket send_json and receive_json

* Fix for (#976): add documentation for websocket send_json and receive_json

* Fix for (#976): serialize receive_str response in receive_json

* Fix for (#976): refactor docs for receive_json method

aiohttp/web_ws.py

@@ -154,6 +154,9 @@ def send_bytes(self, data):
                             type(data))
         self._writer.send(data, binary=True)
 
+    def send_json(self, data, *, dumps=json.dumps):
+        self.send_str(dumps(data))
+
     @asyncio.coroutine
     def write_eof(self):
         if self._eof_sent:
@@ -280,12 +283,8 @@ def receive_bytes(self):
 
     @asyncio.coroutine
     def receive_json(self, *, loads=json.loads):
-        msg = yield from self.receive()
-        if msg.tp != MsgType.text:
-            raise TypeError(
-                "Received message {}:{!r} is not str".format(msg.tp, msg.data)
-            )
-        return msg.json(loads=loads)
+        data = yield from self.receive_str()
+        return loads(data)
 
     def write(self, data):
         raise RuntimeError("Cannot call .write() for websocket")

aiohttp/websocket_client.py

@@ -3,6 +3,7 @@
 import asyncio
 
 import sys
+import json
 from enum import IntEnum
 
 from .websocket import Message
@@ -88,6 +89,9 @@ def send_bytes(self, data):
                             type(data))
         self._writer.send(data, binary=True)
 
+    def send_json(self, data, *, dumps=json.dumps):
+        self.send_str(dumps(data))
+
     @asyncio.coroutine
     def close(self, *, code=1000, message=b''):
         if not self._closed:
@@ -171,6 +175,28 @@ def receive(self):
         finally:
             self._waiting = False
 
+    @asyncio.coroutine
+    def receive_str(self):
+        msg = yield from self.receive()
+        if msg.tp != MsgType.text:
+            raise TypeError(
+                "Received message {}:{!r} is not str".format(msg.tp, msg.data))
+        return msg.data
+
+    @asyncio.coroutine
+    def receive_bytes(self):
+        msg = yield from self.receive()
+        if msg.tp != MsgType.binary:
+            raise TypeError(
+                "Received message {}:{!r} is not bytes".format(msg.tp,
+                                                               msg.data))
+        return msg.data
+
+    @asyncio.coroutine
+    def receive_json(self, *, loads=json.loads):
+        data = yield from self.receive_str()
+        return loads(data)
+
     if PY_35:
         @asyncio.coroutine
         def __aiter__(self):

docs/client_reference.rst

@@ -1277,6 +1277,22 @@ manually.
       :raise TypeError: if data is not :class:`bytes`,
                         :class:`bytearray` or :class:`memoryview`.
 
+   .. method:: send_json(data, *, dumps=json.loads)
+
+      Send *data* to peer as JSON string.
+
+      :param data: data to send.
+
+      :param callable dumps: any :term:`callable` that accepts an object and
+                             returns a JSON string
+                             (:func:`json.dumps` by default).
+
+      :raise RuntimeError: if connection is not started or closing
+
+      :raise ValueError: if data is not serializable object
+
+      :raise TypeError: if value returned by :term:`dumps` is not :class:`str`
+
    .. comethod:: close(*, code=1000, message=b'')
 
       A :ref:`coroutine<coroutine>` that initiates closing handshake by sending
@@ -1306,6 +1322,40 @@ manually.
       :return: :class:`~aiohttp.websocket.Message`, `tp` is types of
          `~aiohttp.MsgType`
 
+   .. coroutinemethod:: receive_str()
+
+      A :ref:`coroutine<coroutine>` that calls :meth:`receive` but
+      also asserts the message type is
+      :const:`~aiohttp.websocket.MSG_TEXT`.
+
+      :return str: peer's message content.
+
+      :raise TypeError: if message is :const:`~aiohttp.websocket.MSG_BINARY`.
+
+   .. coroutinemethod:: receive_bytes()
+
+      A :ref:`coroutine<coroutine>` that calls :meth:`receive` but
+      also asserts the message type is
+      :const:`~aiohttp.websocket.MSG_BINARY`.
+
+      :return bytes: peer's message content.
+
+      :raise TypeError: if message is :const:`~aiohttp.websocket.MSG_TEXT`.
+
+   .. coroutinemethod:: receive_json(*, loads=json.loads)
+
+      A :ref:`coroutine<coroutine>` that calls :meth:`receive_str` and loads
+      the JSON string to a Python dict.
+
+      :param callable loads: any :term:`callable` that accepts
+                              :class:`str` and returns :class:`dict`
+                              with parsed JSON (:func:`json.loads` by
+                              default).
+
+      :return dict: loaded JSON content
+
+      :raise TypeError: if message is :const:`~aiohttp.websocket.MSG_BINARY`.
+      :raise ValueError: if message is not valid JSON.
 
 Utilities
 ---------

docs/web_reference.rst

@@ -830,6 +830,22 @@ WebSocketResponse
       :raise TypeError: if data is not :class:`bytes`,
                         :class:`bytearray` or :class:`memoryview`.
 
+   .. method:: send_json(data, *, dumps=json.loads)
+
+      Send *data* to peer as JSON string.
+
+      :param data: data to send.
+
+      :param callable dumps: any :term:`callable` that accepts an object and
+                             returns a JSON string
+                             (:func:`json.dumps` by default).
+
+      :raise RuntimeError: if connection is not started or closing
+
+      :raise ValueError: if data is not serializable object
+
+      :raise TypeError: if value returned by :term:`dumps` is not :class:`str`
+
    .. coroutinemethod:: close(*, code=1000, message=b'')
 
       A :ref:`coroutine<coroutine>` that initiates closing
@@ -888,9 +904,8 @@ WebSocketResponse
 
    .. coroutinemethod:: receive_json(*, loads=json.loads)
 
-      A :ref:`coroutine<coroutine>` that calls :meth:`receive`, asserts the
-      message type is :const:`~aiohttp.websocket.MSG_TEXT`, and loads the JSON
-      string to a Python dict.
+      A :ref:`coroutine<coroutine>` that calls :meth:`receive_str` and loads the
+      JSON string to a Python dict.
 
       :param callable loads: any :term:`callable` that accepts
                               :class:`str` and returns :class:`dict`

tests/test_web_websocket.py

@@ -65,6 +65,11 @@ def test_nonstarted_send_bytes(self):
         with self.assertRaises(RuntimeError):
             ws.send_bytes(b'bytes')
 
+    def test_nonstarted_send_json(self):
+        ws = WebSocketResponse()
+        with self.assertRaises(RuntimeError):
+            ws.send_json({'type': 'json'})
+
     def test_nonstarted_close(self):
         ws = WebSocketResponse()
         with self.assertRaises(RuntimeError):
@@ -90,6 +95,16 @@ def go():
 
         self.loop.run_until_complete(go())
 
+    def test_nonstarted_receive_json(self):
+
+        @asyncio.coroutine
+        def go():
+            ws = WebSocketResponse()
+            with self.assertRaises(RuntimeError):
+                yield from ws.receive_json()
+
+        self.loop.run_until_complete(go())
+
     def test_receive_str_nonstring(self):
 
         @asyncio.coroutine
@@ -142,6 +157,13 @@ def test_send_bytes_nonbytes(self):
         with self.assertRaises(TypeError):
             ws.send_bytes('string')
 
+    def test_send_json_nonjson(self):
+        req = self.make_request('GET', '/')
+        ws = WebSocketResponse()
+        self.loop.run_until_complete(ws.prepare(req))
+        with self.assertRaises(TypeError):
+            ws.send_json(set())
+
     def test_write(self):
         ws = WebSocketResponse()
         with self.assertRaises(RuntimeError):
@@ -196,6 +218,14 @@ def test_send_bytes_closed(self):
         with self.assertRaises(RuntimeError):
             ws.send_bytes(b'bytes')
 
+    def test_send_json_closed(self):
+        req = self.make_request('GET', '/')
+        ws = WebSocketResponse()
+        self.loop.run_until_complete(ws.prepare(req))
+        self.loop.run_until_complete(ws.close())
+        with self.assertRaises(RuntimeError):
+            ws.send_json({'type': 'json'})
+
     def test_ping_closed(self):
         req = self.make_request('GET', '/')
         ws = WebSocketResponse()

tests/test_web_websocket_functional.py

@@ -40,14 +40,12 @@ def test_websocket_json_invalid_message(create_app_and_client):
     def handler(request):
         ws = web.WebSocketResponse()
         yield from ws.prepare(request)
-        msg = yield from ws.receive()
-
         try:
-            msg.json()
+            yield from ws.receive_json()
         except ValueError:
-            ws.send_str("ValueError raised: '%s'" % msg.data)
+            ws.send_str('ValueError was raised')
         else:
-            raise Exception("No ValueError was raised")
+            raise Exception('No Exception')
         finally:
             yield from ws.close()
         return ws
@@ -59,8 +57,32 @@ def handler(request):
     payload = 'NOT A VALID JSON STRING'
     ws.send_str(payload)
 
-    resp = yield from ws.receive()
-    assert payload in resp.data
+    data = yield from ws.receive_str()
+    assert 'ValueError was raised' in data
+
+
+@pytest.mark.run_loop
+def test_websocket_send_json(create_app_and_client):
+    @asyncio.coroutine
+    def handler(request):
+        ws = web.WebSocketResponse()
+        yield from ws.prepare(request)
+
+        data = yield from ws.receive_json()
+        ws.send_json(data)
+
+        yield from ws.close()
+        return ws
+
+    app, client = yield from create_app_and_client()
+    app.router.add_route('GET', '/', handler)
+
+    ws = yield from client.ws_connect('/')
+    expected_value = 'value'
+    ws.send_json({'test': expected_value})
+
+    data = yield from ws.receive_json()
+    assert data['test'] == expected_value
 
 
 @pytest.mark.run_loop

tests/test_web_websocket_functional_oldstyle.py

@@ -117,6 +117,41 @@ def go():
 
         self.loop.run_until_complete(go())
 
+    def test_send_recv_json(self):
+        closed = helpers.create_future(self.loop)
+
+        @asyncio.coroutine
+        def handler(request):
+            ws = web.WebSocketResponse()
+            yield from ws.prepare(request)
+            data = yield from ws.receive_json()
+            ws.send_json({'response': data['request']})
+            yield from ws.close()
+            closed.set_result(1)
+            return ws
+
+        @asyncio.coroutine
+        def go():
+            _, _, url = yield from self.create_server('GET', '/', handler)
+            resp, reader, writer = yield from self.connect_ws(url)
+            writer.send('{"request": "test"}')
+            msg = yield from reader.read()
+            data = msg.json()
+            self.assertEqual(msg.tp, websocket.MSG_TEXT)
+            self.assertEqual(data['response'], 'test')
+
+            msg = yield from reader.read()
+            self.assertEqual(msg.tp, websocket.MSG_CLOSE)
+            self.assertEqual(msg.data, 1000)
+            self.assertEqual(msg.extra, '')
+
+            writer.close()
+
+            yield from closed
+            resp.close()
+
+        self.loop.run_until_complete(go())
+
     def test_auto_pong_with_closing_by_peer(self):
 
         closed = helpers.create_future(self.loop)

tests/test_websocket_client.py

@@ -334,6 +334,7 @@ def test_send_data_after_close(self, m_req, m_os, WebSocketWriter):
         self.assertRaises(RuntimeError, resp.pong)
         self.assertRaises(RuntimeError, resp.send_str, 's')
         self.assertRaises(RuntimeError, resp.send_bytes, b'b')
+        self.assertRaises(RuntimeError, resp.send_json, {})
 
     @mock.patch('aiohttp.client.WebSocketWriter')
     @mock.patch('aiohttp.client.os')
@@ -357,6 +358,7 @@ def test_send_data_type_errors(self, m_req, m_os, WebSocketWriter):
 
         self.assertRaises(TypeError, resp.send_str, b's')
         self.assertRaises(TypeError, resp.send_bytes, 'b')
+        self.assertRaises(TypeError, resp.send_json, set())
 
     @mock.patch('aiohttp.client.WebSocketWriter')
     @mock.patch('aiohttp.client.os')

tests/test_websocket_client_functional.py

@@ -22,8 +22,8 @@ def handler(request):
     resp = yield from client.ws_connect('/')
     resp.send_str('ask')
 
-    msg = yield from resp.receive()
-    assert msg.data == 'ask/answer'
+    data = yield from resp.receive_str()
+    assert data == 'ask/answer'
     yield from resp.close()
 
 
@@ -46,9 +46,33 @@ def handler(request):
 
     resp.send_bytes(b'ask')
 
-    msg = yield from resp.receive()
-    assert msg.data == b'ask/answer'
+    data = yield from resp.receive_bytes()
+    assert data == b'ask/answer'
+
+    yield from resp.close()
+
+
+@pytest.mark.run_loop
+def test_send_recv_json(create_app_and_client):
+
+    @asyncio.coroutine
+    def handler(request):
+        ws = web.WebSocketResponse()
+        yield from ws.prepare(request)
+
+        data = yield from ws.receive_json()
+        ws.send_json({'response': data['request']})
+        yield from ws.close()
+        return ws
+
+    app, client = yield from create_app_and_client()
+    app.router.add_route('GET', '/', handler)
+    resp = yield from client.ws_connect('/')
+    payload = {'request': 'test'}
+    resp.send_json(payload)
 
+    data = yield from resp.receive_json()
+    assert data['response'] == payload['request']
     yield from resp.close()