Allow homeassistant in MQTT configuration_url schema (#96107)

homeassistant/helpers/config_validation.py

@@ -25,6 +25,7 @@ from uuid import UUID
 import voluptuous as vol
 import voluptuous_serialize
 
+from homeassistant.backports.enum import StrEnum
 from homeassistant.const import (
     ATTR_AREA_ID,
     ATTR_DEVICE_ID,
@@ -106,6 +107,22 @@ from . import script_variables as script_variables_helper, template as template_
 
 TIME_PERIOD_ERROR = "offset {} should be format 'HH:MM', 'HH:MM:SS' or 'HH:MM:SS.F'"
 
+
+class UrlProtocolSchema(StrEnum):
+    """Valid URL protocol schema values."""
+
+    HTTP = "http"
+    HTTPS = "https"
+    HOMEASSISTANT = "homeassistant"
+
+
+EXTERNAL_URL_PROTOCOL_SCHEMA_LIST = frozenset(
+    {UrlProtocolSchema.HTTP, UrlProtocolSchema.HTTPS}
+)
+CONFIGURATION_URL_PROTOCOL_SCHEMA_LIST = frozenset(
+    {UrlProtocolSchema.HOMEASSISTANT, UrlProtocolSchema.HTTP, UrlProtocolSchema.HTTPS}
+)
+
 # Home Assistant types
 byte = vol.All(vol.Coerce(int), vol.Range(min=0, max=255))
 small_float = vol.All(vol.Coerce(float), vol.Range(min=0, max=1))
@@ -728,16 +745,24 @@ def socket_timeout(value: Any | None) -> object:
 
 
 # pylint: disable=no-value-for-parameter
-def url(value: Any) -> str:
+def url(
+    value: Any,
+    _schema_list: frozenset[UrlProtocolSchema] = EXTERNAL_URL_PROTOCOL_SCHEMA_LIST,
+) -> str:
     """Validate an URL."""
     url_in = str(value)
 
-    if urlparse(url_in).scheme in ["http", "https"]:
+    if urlparse(url_in).scheme in _schema_list:
         return cast(str, vol.Schema(vol.Url())(url_in))
 
     raise vol.Invalid("invalid url")
 
 
+def configuration_url(value: Any) -> str:
+    """Validate an URL that allows the homeassistant schema."""
+    return url(value, CONFIGURATION_URL_PROTOCOL_SCHEMA_LIST)
+
+
 def url_no_path(value: Any) -> str:
     """Validate a url without a path."""
     url_in = url(value)