Permit the ServiceBrowser to browse overlong types

bdraco · bdraco · commit 4ea3c5fe4b45 · 2021-06-15T13:42:04.000-10:00
- At least one type "tivo-videostream" exists in the wild
  so we are permissive about what we will look for, and
  strict about what we will announce.
diff --git a/tests/test_services.py b/tests/test_services.py
@@ -1258,3 +1258,20 @@ def test_changing_name_updates_serviceinfo_key():
     assert info_service.key == "mytesthome._homeassistant._tcp.local."
     info_service.name = "YourTestHome._homeassistant._tcp.local."
     assert info_service.key == "yourtesthome._homeassistant._tcp.local."
+
+
+def test_servicebrowser_uses_non_strict_names():
+    """Verify we can look for technically invalid names as we cannot change what others do."""
+
+    # dummy service callback
+    def on_service_state_change(zeroconf, service_type, state_change, name):
+        pass
+
+    zc = r.Zeroconf(interfaces=['127.0.0.1'])
+    browser = ServiceBrowser(zc, ["_tivo-videostream._tcp.local."], [on_service_state_change])
+    browser.cancel()
+
+    # Still fail on completely invalid
+    with pytest.raises(r.BadTypeInNameException):
+        browser = ServiceBrowser(zc, ["tivo-videostream._tcp.local."], [on_service_state_change])
+    zc.close()
diff --git a/tests/utils/test_name.py b/tests/utils/test_name.py
@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+
+"""Unit tests for zeroconf._utils.name."""
+
+import pytest
+
+from zeroconf._utils import name as nameutils
+from zeroconf import BadTypeInNameException
+
+
+def test_service_type_name():
+    """Test overlong service_type_name."""
+    with pytest.raises(BadTypeInNameException):
+        nameutils.service_type_name("Tivo1._tivo-videostream._tcp.local.")
+    nameutils.service_type_name("Tivo1._tivo-videostream._tcp.local.", strict=False)
diff --git a/zeroconf/_utils/name.py b/zeroconf/_utils/name.py
@@ -104,7 +104,8 @@ def service_type_name(type_: str, *, strict: bool = True) -> str:  # pylint: dis
 
         test_service_name = service_name[1:]
 
-        if len(test_service_name) > 15:
+        if strict and len(test_service_name) > 15:
+            # https://datatracker.ietf.org/doc/html/rfc6763#section-7.2
             raise BadTypeInNameException("Service name (%s) must be <= 15 bytes" % test_service_name)
 
         if '--' in test_service_name:
