refactor(kserve): make the torchserve configuration loading more resiliant (#2995)

The many defaults defined cannot currently be used as if the matching
keys are not present in the properties file, it's loading will fail.

This patch fixes that and also ignores lines starting with # as they
should be.

Author: sgaist

kubernetes/kserve/kserve_wrapper/__main__.py

@@ -28,52 +28,42 @@ def parse_config():
         model_store: the path in which the .mar file resides
     """
     separator = "="
-    keys = {}
+    ts_configuration = {}
     config_path = os.environ.get("CONFIG_PATH", DEFAULT_CONFIG_PATH)
 
     logging.info(f"Wrapper: loading configuration from {config_path}")
 
     with open(config_path) as f:
         for line in f:
-            if separator in line:
-                # Find the name and value by splitting the string
-                name, value = line.split(separator, 1)
-
-                # Assign key value pair to dict
-                # strip() removes white space from the ends of strings
-                keys[name.strip()] = value.strip()
-
-    keys["model_snapshot"] = json.loads(keys["model_snapshot"])
-    inference_address, management_address, grpc_inference_port, model_store = (
-        keys["inference_address"],
-        keys["management_address"],
-        keys["grpc_inference_port"],
-        keys["model_store"],
+            if not line.startswith("#"):
+                if separator in line:
+                    name, value = line.split(separator, 1)
+                    ts_configuration[name.strip()] = value.strip()
+
+    ts_configuration["model_snapshot"] = json.loads(
+        ts_configuration.get("model_snapshot", "{}")
     )
 
-    models = keys["model_snapshot"]["models"]
-    model_names = []
+    inference_address = ts_configuration.get(
+        "inference_address", DEFAULT_INFERENCE_ADDRESS
+    )
+    management_address = ts_configuration.get(
+        "management_address", DEFAULT_MANAGEMENT_ADDRESS
+    )
+    grpc_inference_port = ts_configuration.get(
+        "grpc_inference_port", DEFAULT_GRPC_INFERENCE_PORT
+    )
+    model_store = ts_configuration.get("model_store", DEFAULT_MODEL_STORE)
 
     # Get all the model_names
-    for model, value in models.items():
-        model_names.append(model)
+    model_names = ts_configuration["model_snapshot"].get("models", {}).keys()
 
-    if not inference_address:
-        inference_address = DEFAULT_INFERENCE_ADDRESS
     if not model_names:
         model_names = [DEFAULT_MODEL_NAME]
-    if not inference_address:
-        inference_address = DEFAULT_INFERENCE_ADDRESS
-    if not management_address:
-        management_address = DEFAULT_MANAGEMENT_ADDRESS
+
     inf_splits = inference_address.split(":")
-    if not grpc_inference_port:
-        grpc_inference_address = inf_splits[1] + ":" + DEFAULT_GRPC_INFERENCE_PORT
-    else:
-        grpc_inference_address = inf_splits[1] + ":" + grpc_inference_port
+    grpc_inference_address = inf_splits[1] + ":" + grpc_inference_port
     grpc_inference_address = grpc_inference_address.replace("/", "")
-    if not model_store:
-        model_store = DEFAULT_MODEL_STORE
 
     logging.info(
         "Wrapper : Model names %s, inference address %s, management address %s, grpc_inference_address, %s, model store %s",