feat: improve dns cache performance (#1172)

src/zeroconf/_cache.pxd

@@ -1,4 +1,5 @@
 import cython
+
 from ._dns cimport (
     DNSAddress,
     DNSEntry,
@@ -10,6 +11,7 @@ from ._dns cimport (
 )
 
 
+cdef object _UNIQUE_RECORD_TYPES
 cdef object _TYPE_PTR
 
 cdef _remove_key(cython.dict cache, object key, DNSRecord record)

src/zeroconf/_cache.py

@@ -134,14 +134,17 @@ def async_get_unique(self, entry: _UniqueRecordsType) -> Optional[DNSRecord]:
             return None
         return store.get(entry)
 
-    def async_all_by_details(self, name: str, type_: int, class_: int) -> Iterator[DNSRecord]:
+    def async_all_by_details(self, name: _str, type_: int, class_: int) -> Iterator[DNSRecord]:
         """Gets all matching entries by details.
 
         This function is not threadsafe and must be called from
         the event loop.
         """
         key = name.lower()
-        for entry in self.cache.get(key, []):
+        records = self.cache.get(key)
+        if records is None:
+            return
+        for entry in records:
             if _dns_record_matches(entry, key, type_, class_):
                 yield entry
 
@@ -151,15 +154,15 @@ def async_entries_with_name(self, name: str) -> Dict[DNSRecord, DNSRecord]:
         This function is not threadsafe and must be called from
         the event loop.
         """
-        return self.cache.get(name.lower(), {})
+        return self.cache.get(name.lower()) or {}
 
     def async_entries_with_server(self, name: str) -> Dict[DNSRecord, DNSRecord]:
         """Returns a dict of entries whose key matches the server.
 
         This function is not threadsafe and must be called from
         the event loop.
         """
-        return self.service_cache.get(name.lower(), {})
+        return self.service_cache.get(name.lower()) or {}
 
     # The below functions are threadsafe and do not need to be run in the
     # event loop, however they all make copies so they significantly