Keep connection open and lock to prevent duplicate requests (#213)

* Keep connection open and lock to prevent duplicate requests

* option to not update children

* tweaks

* typing

* tweaks

* run tests in the same event loop

* memorize model

* Update kasa/protocol.py

Co-authored-by: Teemu R. <tpr@iki.fi>

* Update kasa/protocol.py

Co-authored-by: Teemu R. <tpr@iki.fi>

* Update kasa/protocol.py

Co-authored-by: Teemu R. <tpr@iki.fi>

* Update kasa/protocol.py

Co-authored-by: Teemu R. <tpr@iki.fi>

* dry

* tweaks

* warn when the event loop gets switched out from under us

* raise on unable to connect multiple times

* fix patch target

* tweaks

* isrot

* reconnect test

* prune

* fix mocking

* fix mocking

* fix test under python 3.7

* fix test under python 3.7

* less patching

* isort

* use mocker to patch

* disable on old python since mocking doesnt work

* avoid disconnect/reconnect cycles

* isort

* Fix hue validation

* Fix latitude_i/longitude_i units

Co-authored-by: Teemu R. <tpr@iki.fi>

kasa/tests/test_protocol.py

@@ -1,4 +1,6 @@
 import json
+import struct
+import sys
 
 import pytest
 
@@ -21,11 +23,47 @@ async def test_protocol_retries(mocker, retry_count):
 
     conn = mocker.patch("asyncio.open_connection", side_effect=aio_mock_writer)
     with pytest.raises(SmartDeviceException):
-        await TPLinkSmartHomeProtocol.query("127.0.0.1", {}, retry_count=retry_count)
+        await TPLinkSmartHomeProtocol("127.0.0.1").query({}, retry_count=retry_count)
 
     assert conn.call_count == retry_count + 1
 
 
+@pytest.mark.skipif(sys.version_info < (3, 8), reason="3.8 is first one with asyncmock")
+@pytest.mark.parametrize("retry_count", [1, 3, 5])
+async def test_protocol_reconnect(mocker, retry_count):
+    remaining = retry_count
+    encrypted = TPLinkSmartHomeProtocol.encrypt('{"great":"success"}')[
+        TPLinkSmartHomeProtocol.BLOCK_SIZE :
+    ]
+
+    def _fail_one_less_than_retry_count(*_):
+        nonlocal remaining
+        remaining -= 1
+        if remaining:
+            raise Exception("Simulated write failure")
+
+    async def _mock_read(byte_count):
+        nonlocal encrypted
+        if byte_count == TPLinkSmartHomeProtocol.BLOCK_SIZE:
+            return struct.pack(">I", len(encrypted))
+        if byte_count == len(encrypted):
+            return encrypted
+
+        raise ValueError(f"No mock for {byte_count}")
+
+    def aio_mock_writer(_, __):
+        reader = mocker.patch("asyncio.StreamReader")
+        writer = mocker.patch("asyncio.StreamWriter")
+        mocker.patch.object(writer, "write", _fail_one_less_than_retry_count)
+        mocker.patch.object(reader, "readexactly", _mock_read)
+        return reader, writer
+
+    protocol = TPLinkSmartHomeProtocol("127.0.0.1")
+    mocker.patch("asyncio.open_connection", side_effect=aio_mock_writer)
+    response = await protocol.query({}, retry_count=retry_count)
+    assert response == {"great": "success"}
+
+
 def test_encrypt():
     d = json.dumps({"foo": 1, "bar": 2})
     encrypted = TPLinkSmartHomeProtocol.encrypt(d)