Asynchronously refresh registry in transformation service (#2060)

Signed-off-by: pyalex <moskalenko.alexey@gmail.com>

sdk/python/feast/feature_store.py

@@ -142,8 +142,10 @@ def refresh_registry(self):
         downloaded synchronously, which may increase latencies if the triggering method is get_online_features()
         """
         registry_config = self.config.get_registry_config()
-        self._registry = Registry(registry_config, repo_path=self.repo_path)
-        self._registry.refresh()
+        registry = Registry(registry_config, repo_path=self.repo_path)
+        registry.refresh()
+
+        self._registry = registry
 
     @log_exceptions_and_usage
     def list_entities(self, allow_cache: bool = False) -> List[Entity]:

sdk/python/feast/infra/transformation_servers/app.py

@@ -1,6 +1,7 @@
 import base64
 import os
 import tempfile
+import threading
 from pathlib import Path
 
 import yaml
@@ -28,9 +29,10 @@
 # Write registry contents for local registries
 config_string = config_bytes.decode("utf-8")
 raw_config = yaml.safe_load(config_string)
-registry_path = raw_config["registry"]
+registry = raw_config["registry"]
+registry_path = registry["path"] if isinstance(registry, dict) else registry
 registry_store_class = get_registry_store_class_from_scheme(registry_path)
-if registry_store_class == LocalRegistryStore:
+if registry_store_class == LocalRegistryStore and not os.path.exists(registry_path):
     registry_base64 = os.environ[REGISTRY_ENV_NAME]
     registry_bytes = base64.b64decode(registry_base64)
     registry_dir = os.path.dirname(registry_path)
@@ -42,6 +44,17 @@
 # Initialize the feature store
 store = FeatureStore(repo_path=str(repo_path.resolve()))
 
+if isinstance(registry, dict) and registry.get("cache_ttl_seconds", 0) > 0:
+    # disable synchronous refresh
+    store.config.registry.cache_ttl_seconds = 0
+
+    # enable asynchronous refresh
+    def async_refresh():
+        store.refresh_registry()
+        threading.Timer(registry["cache_ttl_seconds"], async_refresh).start()
+
+    async_refresh()
+
 # Start the feature transformation server
 port = (
     os.environ.get(FEATURE_TRANSFORMATION_SERVER_PORT_ENV_NAME)