Defer cloud SDK imports across AWS RDS, Azure, and Google Cloud

web/pgadmin/misc/cloud/azure/__init__.py

@@ -25,15 +25,6 @@
 import os
 
 
-from azure.mgmt.rdbms.postgresql_flexibleservers import \
-    PostgreSQLManagementClient
-from azure.identity import AzureCliCredential, DeviceCodeCredential,\
-    AuthenticationRecord
-from azure.mgmt.resource import ResourceManagementClient
-from azure.mgmt.subscription import SubscriptionClient
-from azure.mgmt.rdbms.postgresql_flexibleservers.models import \
-    NameAvailabilityRequest
-
 MODULE_NAME = 'azure'
 
 
@@ -265,6 +256,34 @@ def clear_session():
     return make_json_response(success=1)
 
 
+def _azure_sdk():
+    """Defer heavy Azure SDK imports until required by user actions.
+    Repeat calls are cheap via sys.modules caching.
+    """
+    from types import SimpleNamespace
+    from azure.identity import (
+        AzureCliCredential, DeviceCodeCredential, AuthenticationRecord
+    )
+    from azure.mgmt.rdbms.postgresql_flexibleservers import (
+        PostgreSQLManagementClient
+    )
+    from azure.mgmt.rdbms.postgresql_flexibleservers.models import (
+        NameAvailabilityRequest
+    )
+    from azure.mgmt.resource import ResourceManagementClient
+    from azure.mgmt.subscription import SubscriptionClient
+
+    return SimpleNamespace(
+        AzureCliCredential=AzureCliCredential,
+        DeviceCodeCredential=DeviceCodeCredential,
+        AuthenticationRecord=AuthenticationRecord,
+        PostgreSQLManagementClient=PostgreSQLManagementClient,
+        ResourceManagementClient=ResourceManagementClient,
+        SubscriptionClient=SubscriptionClient,
+        NameAvailabilityRequest=NameAvailabilityRequest,
+    )
+
+
 class Azure:
     def __init__(self, interactive_browser_credential, tenant_id=None,
                  session_token=None, region='eastus'):
@@ -367,7 +386,8 @@ def _get_azure_credentials(self):
 
     def _azure_cli_auth(self):
         if self._cli_credentials is None:
-            self._cli_credentials = AzureCliCredential()
+            sdk = _azure_sdk()
+            self._cli_credentials = sdk.AzureCliCredential()
             self.list_subscriptions()
         return self._cli_credentials
 
@@ -380,8 +400,9 @@ def _azure_interactive_auth_prompt_callback(
         session['azure']['azure_auth_code'] = azure_auth_code
 
     def _azure_interactive_auth(self):
+        sdk = _azure_sdk()
         if self.authentication_record_json is None:
-            _interactive_credential = DeviceCodeCredential(
+            _interactive_credential = sdk.DeviceCodeCredential(
                 tenant_id=self._tenant_id,
                 timeout=180,
                 prompt_callback=self._azure_interactive_auth_prompt_callback,
@@ -392,9 +413,9 @@ def _azure_interactive_auth(self):
             _auth_record = _interactive_credential.authenticate()
             self.authentication_record_json = _auth_record.serialize()
         else:
-            deserialized_auth_record = AuthenticationRecord.deserialize(
+            deserialized_auth_record = sdk.AuthenticationRecord.deserialize(
                 self.authentication_record_json)
-            _interactive_credential = DeviceCodeCredential(
+            _interactive_credential = sdk.DeviceCodeCredential(
                 tenant_id=self._tenant_id,
                 timeout=180,
                 prompt_callback=self._azure_interactive_auth_prompt_callback,
@@ -410,16 +431,23 @@ def _get_azure_client(self, type):
         if type in self._clients:
             return self._clients[type]
 
-        _, _credentials = self._get_azure_credentials()
+        status, _credentials = self._get_azure_credentials()
+        if not status:
+            return None
+
+        try:
+            sdk = _azure_sdk()
+        except ImportError:
+            return None
 
         if type == 'postgresql':
-            client = PostgreSQLManagementClient(_credentials,
-                                                self.subscription_id)
+            client = sdk.PostgreSQLManagementClient(_credentials,
+                                                    self.subscription_id)
         elif type == 'resource':
-            client = ResourceManagementClient(_credentials,
-                                              self.subscription_id)
+            client = sdk.ResourceManagementClient(_credentials,
+                                                  self.subscription_id)
         elif type == 'subscription':
-            client = SubscriptionClient(_credentials)
+            client = sdk.SubscriptionClient(_credentials)
 
         self._clients[type] = client
         return self._clients[type]
@@ -429,9 +457,15 @@ def check_cluster_name_availability(self, cluster_name):
         Checks whether given server name is available or not
         :param cluster_name
         """
+        try:
+            sdk = _azure_sdk()
+        except ImportError as e:
+            return False, str(e)
         postgresql_client = self._get_azure_client('postgresql')
+        if not postgresql_client:
+            return False, 'Failed to initialize Azure client.'
         res = postgresql_client.check_name_availability.execute(
-            NameAvailabilityRequest(
+            sdk.NameAvailabilityRequest(
                 name=cluster_name,
                 type='Microsoft.DBforPostgreSQL/flexibleServers'))
         res = res.__dict__
@@ -442,13 +476,18 @@ def list_subscriptions(self):
         List subscriptions
         :return:
         """
-        subscription_client = self._get_azure_client('subscription')
-        sub_list = subscription_client.subscriptions.list()
         subscriptions_list = []
-        for group in list(sub_list):
-            subscriptions_list.append(
-                {'subscription_id': group.subscription_id,
-                 'subscription_name': group.display_name})
+        try:
+            subscription_client = self._get_azure_client('subscription')
+            if not subscription_client:
+                return subscriptions_list
+            sub_list = subscription_client.subscriptions.list()
+            for group in list(sub_list):
+                subscriptions_list.append(
+                    {'subscription_id': group.subscription_id,
+                     'subscription_name': group.display_name})
+        except ImportError:
+            return subscriptions_list
         return subscriptions_list
 
     def list_resource_groups(self, subscription_id):
@@ -458,14 +497,19 @@ def list_resource_groups(self, subscription_id):
         :return:
         """
         self.subscription_id = subscription_id
-        resource_client = self._get_azure_client('resource')
-        group_list = resource_client.resource_groups.list()
         resource_groups_list = []
-        for group in list(group_list):
-            resource_groups_list.append(
-                {'label': group.name,
-                 'value': group.name,
-                 'region': group.location})
+        try:
+            resource_client = self._get_azure_client('resource')
+            if not resource_client:
+                return resource_groups_list
+            group_list = resource_client.resource_groups.list()
+            for group in list(group_list):
+                resource_groups_list.append(
+                    {'label': group.name,
+                     'value': group.name,
+                     'region': group.location})
+        except ImportError:
+            return resource_groups_list
         return resource_groups_list
 
     def list_regions(self, subscription_id):
@@ -475,13 +519,18 @@ def list_regions(self, subscription_id):
         :return:
         """
         self.subscription_id = subscription_id
-        subscription_client = self._get_azure_client('subscription')
-        locations = subscription_client.subscriptions.list_locations(
-            subscription_id=self.subscription_id)
         locations_list = []
-        for location in locations:
-            locations_list.append(
-                {'label': location.display_name, 'value': location.name})
+        try:
+            subscription_client = self._get_azure_client('subscription')
+            if not subscription_client:
+                return locations_list
+            locations = subscription_client.subscriptions.list_locations(
+                subscription_id=self.subscription_id)
+            for location in locations:
+                locations_list.append(
+                    {'label': location.display_name, 'value': location.name})
+        except ImportError:
+            return locations_list
         return locations_list
 
     def is_zone_redundant_ha_supported(self, region):
@@ -492,8 +541,10 @@ def is_zone_redundant_ha_supported(self, region):
         else:
             self._available_capabilities_list = \
                 self._get_available_capabilities_list(region)
-            return self._available_capabilities_list[0][
-                'zone_redundant_ha_supported']
+            if self._available_capabilities_list:
+                return self._available_capabilities_list[0][
+                    'zone_redundant_ha_supported']
+            return False
 
     def list_azure_availability_zones(self, region):
         """
@@ -597,6 +648,8 @@ def _get_available_capabilities_object(self, region):
         :return: azure capabilities object
         """
         postgresql_client = self._get_azure_client('postgresql')
+        if not postgresql_client:
+            return []
         return postgresql_client.location_based_capabilities.execute(
             location_name=region)
 

web/pgadmin/misc/cloud/azure/tests/test_azure_session_state.py

@@ -206,3 +206,38 @@ def runTest(self):
             "cloud.azure must not import the unsafe deserializer")
         self.assertNotIn(forbidden + '.dumps(', src)
         self.assertNotIn(forbidden + '.loads(', src)
+
+
+class TestAzureImportErrorHandling(
+        _SkipServerSetUpMixin, BaseTestGenerator):
+    """Azure methods must handle ImportError cleanly without raising."""
+
+    scenarios = [('default', dict())]
+
+    def runTest(self):
+        from unittest.mock import patch
+        from pgadmin.misc.cloud.azure import Azure
+        import pgadmin.misc.cloud.azure as azure_mod
+
+        a = Azure.from_state({'tenant_id': 'tid'})
+        with patch.object(
+                azure_mod, '_azure_sdk',
+                side_effect=ImportError('No module named azure.mgmt')):
+            client = a._get_azure_client('postgresql')
+            self.assertIsNone(client)
+
+            avail, msg = a.check_cluster_name_availability('server')
+            self.assertFalse(avail)
+            self.assertIn('azure.mgmt', msg)
+
+            subs = a.list_subscriptions()
+            self.assertEqual(subs, [])
+
+            rgs = a.list_resource_groups('sub-1')
+            self.assertEqual(rgs, [])
+
+            regs = a.list_regions('sub-1')
+            self.assertEqual(regs, [])
+
+            ha = a.is_zone_redundant_ha_supported('eastus')
+            self.assertFalse(ha)