Add OTBR discovery (#4040)

* Add OTBR discovery

* Fix typo

* Move constants to correct file

* Drop Web Service port

* Use existing port constant

supervisor/discovery/services/otbr.py

@@ -0,0 +1,13 @@
+"""Discovery service for OpenThread Border Router."""
+import voluptuous as vol
+
+from ...validate import network_port
+from ..const import ATTR_HOST, ATTR_PORT
+
+# pylint: disable=no-value-for-parameter
+SCHEMA = vol.Schema(
+    {
+        vol.Required(ATTR_HOST): str,
+        vol.Required(ATTR_PORT): network_port,
+    }
+)

tests/discovery/test_otbr.py

@@ -0,0 +1,22 @@
+"""Test OTBR discovery."""
+
+import pytest
+import voluptuous as vol
+
+from supervisor.discovery.validate import valid_discovery_config
+
+
+def test_good_config():
+    """Test good OTBR config."""
+
+    valid_discovery_config(
+        "otbr",
+        {"host": "test", "port": 3812},
+    )
+
+
+def test_bad_config():
+    """Test bad OTBR config."""
+
+    with pytest.raises(vol.Invalid):
+        valid_discovery_config("otbr", {"host": "test"})