diff --git a/acto/checker/checker_set.py b/acto/checker/checker_set.py
index aebf6da607..52a7167569 100644
--- a/acto/checker/checker_set.py
+++ b/acto/checker/checker_set.py
@@ -7,7 +7,7 @@
 from acto.checker.impl.health import HealthChecker
 from acto.checker.impl.operator_log import OperatorLogChecker
 from acto.common import flatten_dict
-from acto.input import InputModel
+from acto.input.input import InputModel
 from acto.oracle_handle import OracleHandle
 from acto.result import OracleResults
 from acto.snapshot import Snapshot
diff --git a/acto/checker/impl/consistency.py b/acto/checker/impl/consistency.py
index 3e3335063e..8adb25ab4a 100644
--- a/acto/checker/impl/consistency.py
+++ b/acto/checker/impl/consistency.py
@@ -19,8 +19,8 @@
     invalid_input_message,
     is_subfield,
 )
-from acto.input import InputModel
 from acto.input.get_matched_schemas import find_matched_schema
+from acto.input.input import InputModel
 from acto.input.property_attribute import PropertyAttribute
 from acto.k8s_util.k8sutil import canonicalize_quantity
 from acto.result import ConsistencyOracleResult, InvalidInputResult
diff --git a/acto/checker/impl/tests/test_state.py b/acto/checker/impl/tests/test_state.py
index fc7bcc2f39..fa562de08c 100644
--- a/acto/checker/impl/tests/test_state.py
+++ b/acto/checker/impl/tests/test_state.py
@@ -11,7 +11,7 @@
 from acto.checker.impl.consistency import ConsistencyChecker
 from acto.checker.impl.tests import load_snapshot
 from acto.common import Diff, PropertyPath
-from acto.input import DeterministicInputModel
+from acto.input.input import DeterministicInputModel
 from acto.result import (
     ConsistencyOracleResult,
     InvalidInputResult,
diff --git a/acto/engine.py b/acto/engine.py
index 7ebaa80d5e..665b877865 100644
--- a/acto/engine.py
+++ b/acto/engine.py
@@ -21,8 +21,7 @@
 from acto.common import kubernetes_client, print_event
 from acto.constant import CONST
 from acto.deploy import Deploy
-from acto.input import InputModel
-from acto.input.input import DeterministicInputModel
+from acto.input.input import DeterministicInputModel, InputModel
 from acto.input.testcase import TestCase
 from acto.input.testplan import TestGroup
 from acto.input.value_with_schema import ValueWithSchema, attach_schema_to_value
diff --git a/acto/input/__init__.py b/acto/input/__init__.py
index f5c2d4db26..e69de29bb2 100644
--- a/acto/input/__init__.py
+++ b/acto/input/__init__.py
@@ -1,2 +0,0 @@
-from .input import DeterministicInputModel, InputModel
-from .testcase import TestCase
diff --git a/acto/reproduce.py b/acto/reproduce.py
index 43557c49df..9544ad21a1 100644
--- a/acto/reproduce.py
+++ b/acto/reproduce.py
@@ -13,8 +13,8 @@
 
 from acto import DEFAULT_KUBERNETES_VERSION
 from acto.engine import Acto
-from acto.input import TestCase
 from acto.input.input import DeterministicInputModel
+from acto.input.testcase import TestCase
 from acto.input.testplan import TestGroup
 from acto.input.value_with_schema import ValueWithSchema
 from acto.input.valuegenerator import extract_schema_with_value_generator
diff --git a/acto/schema/object.py b/acto/schema/object.py
index f7b70fef7c..664c76ffb0 100644
--- a/acto/schema/object.py
+++ b/acto/schema/object.py
@@ -31,12 +31,8 @@ def __init__(self, path: list, schema: dict) -> None:
         self.properties: dict[str, BaseSchema] = {}
         self.additional_properties = None
         self.required = []
-        logger = get_thread_logger(with_prefix=True)
         if "properties" not in schema and "additionalProperties" not in schema:
-            logger.warning(
-                "Object schema %s does not have properties nor additionalProperties",
-                self.path,
-            )
+            return
         if "properties" in schema:
             for property_key, property_schema in schema["properties"].items():
                 self.properties[property_key] = extract_schema(
diff --git a/acto/serialization.py b/acto/serialization.py
index 5756f84794..b0f1b4d01b 100644
--- a/acto/serialization.py
+++ b/acto/serialization.py
@@ -9,7 +9,7 @@
 from deepdiff.helper import NotPresent
 
 from acto.common import Diff, PropertyPath
-from acto.input import TestCase
+from acto.input.testcase import TestCase
 
 
 def _serialize_decimal(value: decimal.Decimal):
diff --git a/test/integration_tests/test_cassop_bugs.py b/test/integration_tests/test_cassop_bugs.py
index 28fc525a0a..db97c86674 100644
--- a/test/integration_tests/test_cassop_bugs.py
+++ b/test/integration_tests/test_cassop_bugs.py
@@ -1,4 +1,5 @@
 """Integration tests for cass-operator bugs."""
+
 import json
 import os
 import pathlib
@@ -8,7 +9,7 @@
 
 from acto import acto_config
 from acto.checker.checker_set import CheckerSet
-from acto.input import DeterministicInputModel, InputModel
+from acto.input.input import DeterministicInputModel, InputModel
 from acto.lib.operator_config import OperatorConfig
 from acto.post_process.post_diff_test import DiffTestResult, PostDiffTest
 from acto.snapshot import Snapshot
diff --git a/test/integration_tests/test_crdb_bugs.py b/test/integration_tests/test_crdb_bugs.py
index a1ff260058..310019056a 100644
--- a/test/integration_tests/test_crdb_bugs.py
+++ b/test/integration_tests/test_crdb_bugs.py
@@ -1,4 +1,5 @@
 """Integration tests for cockroach-operator bugs."""
+
 import json
 import os
 import pathlib
@@ -8,7 +9,7 @@
 
 from acto import acto_config
 from acto.checker.checker_set import CheckerSet
-from acto.input import DeterministicInputModel, InputModel
+from acto.input.input import DeterministicInputModel, InputModel
 from acto.lib.operator_config import OperatorConfig
 from acto.snapshot import Snapshot
 
diff --git a/test/integration_tests/test_learn.py b/test/integration_tests/test_learn.py
new file mode 100644
index 0000000000..317c026256
--- /dev/null
+++ b/test/integration_tests/test_learn.py
@@ -0,0 +1,52 @@
+import json
+import os
+import pathlib
+import unittest
+from datetime import datetime
+
+from acto.engine import Acto, apply_testcase
+from acto.input.input import DeterministicInputModel
+from acto.lib.operator_config import OperatorConfig
+
+test_dir = pathlib.Path(__file__).parent.resolve()
+test_data_dir = os.path.join(test_dir, "test_data")
+
+
+class TestLearnPhase(unittest.TestCase):
+    """Integration tests for Acto's learning phase."""
+
+    def test_statefulset_operator(self):
+        """Test statefulset operator."""
+        workdir_path = f"testrun-{datetime.now().strftime('%Y-%m-%d-%H-%M')}"
+        os.makedirs(workdir_path, exist_ok=True)
+
+        config_path = os.path.join(
+            test_data_dir, "elastic-on-k8s", "config.json"
+        )
+        with open(config_path, "r", encoding="utf-8") as config_file:
+            config = json.load(config_file)
+            if "monkey_patch" in config:
+                del config["monkey_patch"]
+            config = OperatorConfig.model_validate(config)
+
+        context_cache = os.path.join(
+            os.path.dirname(config.seed_custom_resource), "context.json"
+        )
+
+        Acto(
+            workdir_path=workdir_path,
+            operator_config=config,
+            cluster_runtime="KIND",
+            preload_images_=None,
+            context_file=context_cache,
+            helper_crd=None,
+            num_workers=1,
+            num_cases=1,
+            dryrun=False,
+            analysis_only=False,
+            is_reproduce=False,
+            input_model=DeterministicInputModel,
+            apply_testcase_f=apply_testcase,
+            delta_from=None,
+            focus_fields=config.focus_fields,
+        )
diff --git a/test/integration_tests/test_rbop_bugs.py b/test/integration_tests/test_rbop_bugs.py
index 7152e6a019..db5a4fe69c 100644
--- a/test/integration_tests/test_rbop_bugs.py
+++ b/test/integration_tests/test_rbop_bugs.py
@@ -9,7 +9,7 @@
 
 from acto import acto_config
 from acto.checker.checker_set import CheckerSet
-from acto.input import DeterministicInputModel, InputModel
+from acto.input.input import DeterministicInputModel, InputModel
 from acto.lib.operator_config import OperatorConfig
 from acto.snapshot import Snapshot