adding unit tests

src/sonic-host-services/.gitignore

@@ -14,3 +14,4 @@ dist/
 .coverage
 coverage.xml
 htmlcov/
+/.pytest_cache/

src/sonic-host-services/pytest.ini

@@ -1,2 +1,2 @@
 [pytest]
-addopts = --cov=scripts --cov-report html --cov-report term --cov-report xml
+addopts = --cov=scripts --cov-report html --cov-report term --cov-report xml --ignore=tests/hostcfgd/test_vectors.py

src/sonic-host-services/tests/hostcfgd/hostcfgd_test.py

@@ -0,0 +1,78 @@
+import importlib.machinery
+import importlib.util
+import os
+import sys
+import swsssdk
+
+from parameterized import parameterized
+from unittest import TestCase, mock
+from tests.hostcfgd.test_vectors import hostcfgdTestVector
+from tests.hostcfgd.mock_configdb import MockConfigDb
+
+
+swsssdk.ConfigDBConnector = MockConfigDb
+test_path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+modules_path = os.path.dirname(test_path)
+scripts_path = os.path.join(modules_path, "scripts")
+sys.path.insert(0, modules_path)
+
+# Load the file under test
+hostcfgd_path = os.path.join(scripts_path, 'hostcfgd')
+loader = importlib.machinery.SourceFileLoader('hostcfgd', hostcfgd_path)
+spec = importlib.util.spec_from_loader(loader.name, loader)
+hostcfgd = importlib.util.module_from_spec(spec)
+loader.exec_module(hostcfgd)
+sys.modules['hostcfgd'] = hostcfgd
+
+
+class TestHostcfgd(TestCase):
+    """
+        Test hostcfd daemon - feature
+    """
+    def __verify_table(self, table, expected_table):
+        """
+            verify config db tables
+
+            Compares Config DB table (FEATURE) with expected output table
+
+            Args:
+                table(dict): Current Config Db table
+                expected_table(dict): Expected Config Db table
+
+            Returns:
+                None
+        """
+        isEqual = len(table) == len(expected_table)
+        if isEqual:
+            for key, fields in expected_table.items():
+                isEqual = isEqual and key in table
+                if isEqual:
+                    for field, value in fields.items():
+                        isEqual = isEqual and value == table[key][field]
+                        if not isEqual:
+                            break;
+                else:
+                    break
+        return isEqual
+
+    @parameterized.expand(hostcfgdTestVector)
+    def test_hostcfgd(self, name, testData):
+        """
+            Test hostcfd daemon initialization
+
+            Args:
+                name(str): test name
+                test_data(dict): test data which contains initial Config Db tables, and expected results
+
+            Returns:
+                None
+        """
+        MockConfigDb.set_config_db(testData["config_db"])
+        with mock.patch("hostcfgd.subprocess") as mockSubprocess:
+            hostConfigDaemon = hostcfgd.HostConfigDaemon()
+            hostConfigDaemon.update_all_feature_states()
+            assert self.__verify_table(
+                MockConfigDb.get_config_db()["FEATURE"],
+                testData["expected_config_db"]["FEATURE"]
+            ), "Test failed for test data: {0}".format(testData)
+            mockSubprocess.check_call.assert_has_calls(testData["expected_subprocess_calls"], any_order=True)

src/sonic-host-services/tests/hostcfgd/mock_configdb.py

@@ -0,0 +1,32 @@
+class MockConfigDb(object):
+    """
+        Mock Config DB which responds to data tables requests and store updates to the data table
+    """
+    STATE_DB = None
+    CONFIG_DB = None
+
+    def __init__(self):
+        pass
+
+    @staticmethod
+    def set_config_db(test_config_db):
+        MockConfigDb.CONFIG_DB = test_config_db
+
+    @staticmethod
+    def get_config_db():
+        return MockConfigDb.CONFIG_DB
+
+    def connect(self, wait_for_init=True, retry_on=True):
+        pass
+
+    def get(self, db_id, key, field):
+        return MockConfigDb.CONFIG_DB[key][field]
+
+    def get_entry(self, key, field):
+        return MockConfigDb.CONFIG_DB[key][field]
+
+    def set_entry(self, key, field, data):
+        MockConfigDb.CONFIG_DB[key][field] = data
+
+    def get_table(self, table_name):
+        return MockConfigDb.CONFIG_DB[table_name]