Add support for Mqtt protocol version 5 (#82260)

homeassistant/components/mqtt/client.py

@@ -57,6 +57,7 @@ from .const import (
     DEFAULT_QOS,
     MQTT_CONNECTED,
     MQTT_DISCONNECTED,
+    PROTOCOL_5,
     PROTOCOL_31,
 )
 from .models import (
@@ -272,8 +273,10 @@ class MqttClientSetup:
         # should be able to optionally rely on MQTT.
         import paho.mqtt.client as mqtt  # pylint: disable=import-outside-toplevel
 
-        if config.get(CONF_PROTOCOL, DEFAULT_PROTOCOL) == PROTOCOL_31:
+        if (protocol := config.get(CONF_PROTOCOL, DEFAULT_PROTOCOL)) == PROTOCOL_31:
             proto = mqtt.MQTTv31
+        elif protocol == PROTOCOL_5:
+            proto = mqtt.MQTTv5
         else:
             proto = mqtt.MQTTv311
 
@@ -558,8 +561,9 @@ class MQTT:
         self,
         _mqttc: mqtt.Client,
         _userdata: None,
-        _flags: dict[str, Any],
+        _flags: dict[str, int],
         result_code: int,
+        properties: mqtt.Properties | None = None,
     ) -> None:
         """On connect callback.
 
@@ -677,9 +681,13 @@ class MQTT:
         _mqttc: mqtt.Client,
         _userdata: None,
         mid: int,
-        _granted_qos: tuple[Any, ...] | None = None,
+        _granted_qos_reason: tuple[int, ...] | mqtt.ReasonCodes | None = None,
+        _properties_reason: mqtt.ReasonCodes | None = None,
     ) -> None:
         """Publish / Subscribe / Unsubscribe callback."""
+        # The callback signature for on_unsubscribe is different from on_subscribe
+        # see https://github.com/eclipse/paho.mqtt.python/issues/687
+        # properties and reasoncodes are not used in Home Assistant
         self.hass.add_job(self._mqtt_handle_mid, mid)
 
     async def _mqtt_handle_mid(self, mid: int) -> None:
@@ -695,7 +703,11 @@ class MQTT:
                 self._pending_operations[mid] = asyncio.Event()
 
     def _mqtt_on_disconnect(
-        self, _mqttc: mqtt.Client, _userdata: None, result_code: int
+        self,
+        _mqttc: mqtt.Client,
+        _userdata: None,
+        result_code: int,
+        properties: mqtt.Properties | None = None,
     ) -> None:
         """Disconnected callback."""
         self.connected = False

homeassistant/components/mqtt/config_flow.py

@@ -683,7 +683,11 @@ def try_connection(
     result: queue.Queue[bool] = queue.Queue(maxsize=1)
 
     def on_connect(
-        client_: mqtt.Client, userdata: None, flags: dict[str, Any], result_code: int
+        client_: mqtt.Client,
+        userdata: None,
+        flags: dict[str, Any],
+        result_code: int,
+        properties: mqtt.Properties | None = None,
     ) -> None:
         """Handle connection result."""
         result.put(result_code == mqtt.CONNACK_ACCEPTED)

homeassistant/components/mqtt/const.py

@@ -46,7 +46,8 @@ DEFAULT_RETAIN = False
 
 PROTOCOL_31 = "3.1"
 PROTOCOL_311 = "3.1.1"
-SUPPORTED_PROTOCOLS = [PROTOCOL_31, PROTOCOL_311]
+PROTOCOL_5 = "5"
+SUPPORTED_PROTOCOLS = [PROTOCOL_31, PROTOCOL_311, PROTOCOL_5]
 
 DEFAULT_PORT = 1883
 DEFAULT_KEEPALIVE = 60

tests/components/mqtt/test_config_flow.py

@@ -194,6 +194,45 @@ async def test_user_connection_works(
     assert len(mock_finish_setup.mock_calls) == 1
 
 
+async def test_user_v5_connection_works(
+    hass, mock_try_connection, mock_finish_setup, mqtt_client_mock
+):
+    """Test we can finish a config flow."""
+    mock_try_connection.return_value = True
+
+    result = await hass.config_entries.flow.async_init(
+        "mqtt", context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == "form"
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], {"broker": "127.0.0.1", "advanced_options": True}
+    )
+
+    assert result["step_id"] == "broker"
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"],
+        user_input={
+            mqtt.CONF_BROKER: "another-broker",
+            mqtt.CONF_PORT: 2345,
+            mqtt.CONF_PROTOCOL: "5",
+        },
+    )
+    assert result["type"] == "create_entry"
+    assert result["result"].data == {
+        "broker": "another-broker",
+        "discovery": True,
+        "discovery_prefix": "homeassistant",
+        "port": 2345,
+        "protocol": "5",
+    }
+    # Check we tried the connection
+    assert len(mock_try_connection.mock_calls) == 1
+    # Check config entry got setup
+    assert len(mock_finish_setup.mock_calls) == 1
+
+
 async def test_user_connection_fails(
     hass, mock_try_connection_time_out, mock_finish_setup
 ):