App Config Provider - Minimum Up Time

sdk/appconfiguration/azure-appconfiguration-provider/CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Features Added
 
 - Added on_refresh_success callback to load method. This callback is called when the refresh method successfully refreshes the configuration.
+- Added minimum up time. This is the minimum amount of time the provider will try to be up before throwing an error. This is to prevent quick restart loops.
 
 ### Breaking Changes
 

sdk/appconfiguration/azure-appconfiguration-provider/azure/appconfiguration/provider/_azureappconfigurationprovider.py

@@ -7,6 +7,7 @@
 import json
 import random
 import time
+import datetime
 from threading import Lock
 import logging
 from typing import (
@@ -51,6 +52,8 @@
 
 logger = logging.getLogger(__name__)
 
+min_uptime = 5
+
 
 @overload
 def load(
@@ -151,6 +154,7 @@ def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
     credential: Optional["TokenCredential"] = kwargs.pop("credential", None)
     connection_string: Optional[str] = kwargs.pop("connection_string", None)
     key_vault_options: Optional[AzureAppConfigurationKeyVaultOptions] = kwargs.pop("key_vault_options", None)
+    start_time = datetime.datetime.now()
 
     # Update endpoint and credential if specified positionally.
     if len(args) > 2:
@@ -186,7 +190,11 @@ def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
     provider = _buildprovider(
         connection_string, endpoint, credential, uses_key_vault="UsesKeyVault" in headers, **kwargs
     )
-    provider._load_all(headers=headers)
+    try:
+        provider._load_all(headers=headers)
+    except Exception as e:
+        _prekill(start_time)
+        raise e
 
     # Refresh-All sentinels are not updated on load_all, as they are not necessarily included in the provider.
     for (key, label), etag in provider._refresh_on.items():
@@ -203,10 +211,23 @@ def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
                         label,
                     )
                 else:
+                    _prekill(start_time)
                     raise e
+            except Exception as e:
+                _prekill(start_time)
+                raise e
     return provider
 
 
+def _prekill(start_time: datetime.datetime) -> None:
+    # We want to make sure we are up a minimum amount of time before we kill the process. Otherwise, we could get stuck
+    # in a quick restart loop.
+    min_time = datetime.timedelta(seconds=min_uptime)
+    current_time = datetime.datetime.now()
+    if current_time - start_time < min_time:
+        time.sleep(min_time - (current_time - start_time))
+
+
 def _get_headers(request_type, **kwargs) -> str:
     headers = kwargs.pop("headers", {})
     if os.environ.get(REQUEST_TRACING_DISABLED_ENVIRONMENT_VARIABLE, default="").lower() != "true":

sdk/appconfiguration/azure-appconfiguration-provider/azure/appconfiguration/provider/aio/_azureappconfigurationproviderasync.py

@@ -4,6 +4,7 @@
 # license information.
 # -------------------------------------------------------------------------
 import json
+import datetime
 from asyncio.locks import Lock
 import logging
 from typing import (
@@ -42,6 +43,7 @@
     _get_headers,
     _RefreshTimer,
     _build_sentinel,
+    _prekill,
 )
 from .._user_agent import USER_AGENT
 
@@ -153,6 +155,7 @@ async def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
     credential: Optional["AsyncTokenCredential"] = kwargs.pop("credential", None)
     connection_string: Optional[str] = kwargs.pop("connection_string", None)
     key_vault_options: Optional[AzureAppConfigurationKeyVaultOptions] = kwargs.pop("key_vault_options", None)
+    start_time = datetime.datetime.now()
 
     # Update endpoint and credential if specified positionally.
     if len(args) > 2:
@@ -186,7 +189,12 @@ async def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
 
     headers = _get_headers("Startup", **kwargs)
     provider = _buildprovider(connection_string, endpoint, credential, **kwargs)
-    await provider._load_all(headers=headers)
+
+    try:
+        await provider._load_all(headers=headers)
+    except Exception as e:
+        _prekill(start_time)
+        raise e
 
     # Refresh-All sentinels are not updated on load_all, as they are not necessarily included in the provider.
     for (key, label), etag in provider._refresh_on.items():
@@ -204,7 +212,11 @@ async def load(*args, **kwargs) -> "AzureAppConfigurationProvider":
                     )
                     provider._refresh_on[(key, label)] = None
                 else:
+                    _prekill(start_time)
                     raise e
+            except Exception as e:
+                _prekill(start_time)
+                raise e
     return provider
 
 

sdk/appconfiguration/azure-appconfiguration-provider/tests/test_provider.py

@@ -7,6 +7,10 @@
 from devtools_testutils import recorded_by_proxy
 from preparers import app_config_decorator
 from testcase import AppConfigTestCase
+import datetime
+from unittest.mock import patch
+
+from azure.appconfiguration.provider._azureappconfigurationprovider import _prekill
 
 
 class TestAppConfigurationProvider(AppConfigTestCase):
@@ -104,6 +108,18 @@ def test_provider_secret_resolver_options(self, appconfiguration_connection_stri
         )
         assert client["secret"] == "Reslover Value"
 
+    # method: _prekill
+    @patch("time.sleep")
+    def test_prekill(self, mock_sleep, **kwargs):
+        start_time = datetime.datetime.now()
+        _prekill(start_time)
+        assert mock_sleep.call_count == 1
+
+        mock_sleep.reset_mock()
+        start_time = datetime.datetime.now() - datetime.timedelta(seconds=10)
+        _prekill(start_time)
+        mock_sleep.assert_not_called()
+
 
 def secret_resolver(secret_id):
     return "Reslover Value"