From fae56ef2bac8a0b3b64dae0839aa2460716d9ca3 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Mon, 10 Jan 2022 11:17:53 +0100
Subject: [PATCH 01/12] Fix mypy errors

---
 .github/workflows/python_build.yml            |  2 ++
 aws_lambda_powertools/metrics/metrics.py      |  5 +--
 aws_lambda_powertools/shared/functions.py     | 12 ++++---
 .../utilities/batch/exceptions.py             |  2 +-
 aws_lambda_powertools/utilities/batch/sqs.py  | 11 +++++--
 .../utilities/idempotency/idempotency.py      |  4 +--
 .../utilities/idempotency/persistence/base.py |  8 ++---
 .../idempotency/persistence/dynamodb.py       |  2 +-
 .../utilities/parameters/base.py              | 31 ++++++++++---------
 .../utilities/parameters/ssm.py               |  2 +-
 .../utilities/parser/envelopes/apigw.py       |  2 +-
 .../utilities/parser/envelopes/apigwv2.py     |  2 +-
 .../parser/envelopes/event_bridge.py          |  2 +-
 .../utilities/parser/envelopes/sns.py         |  2 +-
 .../utilities/parser/models/alb.py            |  4 +--
 .../utilities/parser/models/apigw.py          |  4 +--
 .../utilities/parser/models/apigwv2.py        |  4 +--
 .../utilities/parser/models/cloudwatch.py     |  4 +--
 .../utilities/parser/models/dynamodb.py       |  4 +--
 .../utilities/parser/models/event_bridge.py   |  4 +--
 .../utilities/parser/models/kinesis.py        |  4 +--
 .../parser/models/s3_object_event.py          |  4 +--
 .../utilities/parser/models/sns.py            |  4 +--
 .../utilities/parser/models/sqs.py            |  4 +--
 24 files changed, 70 insertions(+), 57 deletions(-)

diff --git a/.github/workflows/python_build.yml b/.github/workflows/python_build.yml
index 17aa08ead81..98a574bd94d 100644
--- a/.github/workflows/python_build.yml
+++ b/.github/workflows/python_build.yml
@@ -30,6 +30,8 @@ jobs:
         run: make dev
       - name: Formatting and Linting
         run: make lint
+      - name: Typing
+        run: make mypy
       - name: Test with pytest
         run: make test
       - name: Security baseline
diff --git a/aws_lambda_powertools/metrics/metrics.py b/aws_lambda_powertools/metrics/metrics.py
index 927b6873648..00e083d4a7f 100644
--- a/aws_lambda_powertools/metrics/metrics.py
+++ b/aws_lambda_powertools/metrics/metrics.py
@@ -53,7 +53,7 @@ def lambda_handler():
     ----------
     service : str, optional
         service name to be used as metric dimension, by default "service_undefined"
-    namespace : str
+    namespace : str, optional
         Namespace for metrics
 
     Raises
@@ -209,5 +209,6 @@ def __add_cold_start_metric(self, context: Any) -> None:
             logger.debug("Adding cold start metric and function_name dimension")
             with single_metric(name="ColdStart", unit=MetricUnit.Count, value=1, namespace=self.namespace) as metric:
                 metric.add_dimension(name="function_name", value=context.function_name)
-                metric.add_dimension(name="service", value=self.service)
+                if self.service:
+                    metric.add_dimension(name="service", value=str(self.service))
                 is_cold_start = False
diff --git a/aws_lambda_powertools/shared/functions.py b/aws_lambda_powertools/shared/functions.py
index 11c4e4ce77c..37621f8274a 100644
--- a/aws_lambda_powertools/shared/functions.py
+++ b/aws_lambda_powertools/shared/functions.py
@@ -1,4 +1,4 @@
-from typing import Any, Optional, Union
+from typing import Optional, Union
 
 
 def strtobool(value: str) -> bool:
@@ -38,21 +38,23 @@ def resolve_truthy_env_var_choice(env: str, choice: Optional[bool] = None) -> bo
     return choice if choice is not None else strtobool(env)
 
 
-def resolve_env_var_choice(env: Any, choice: Optional[Any] = None) -> Union[bool, Any]:
+def resolve_env_var_choice(
+    env: Optional[str] = None, choice: Optional[Union[str, float]] = None
+) -> Optional[Union[str, float]]:
     """Pick explicit choice over env, if available, otherwise return env value received
 
     NOTE: Environment variable should be resolved by the caller.
 
     Parameters
     ----------
-    env : Any
+    env : str, Optional
         environment variable actual value
-    choice : bool
+    choice : str|float, optional
         explicit choice
 
     Returns
     -------
-    choice : str
+    choice : str, Optional
         resolved choice as either bool or environment value
     """
     return choice if choice is not None else env
diff --git a/aws_lambda_powertools/utilities/batch/exceptions.py b/aws_lambda_powertools/utilities/batch/exceptions.py
index dc4ca300c7c..d90c25f12bc 100644
--- a/aws_lambda_powertools/utilities/batch/exceptions.py
+++ b/aws_lambda_powertools/utilities/batch/exceptions.py
@@ -5,7 +5,7 @@
 from types import TracebackType
 from typing import List, Optional, Tuple, Type
 
-ExceptionInfo = Tuple[Type[BaseException], BaseException, TracebackType]
+ExceptionInfo = Tuple[Optional[Type[BaseException]], Optional[BaseException], Optional[TracebackType]]
 
 
 class BaseBatchProcessingError(Exception):
diff --git a/aws_lambda_powertools/utilities/batch/sqs.py b/aws_lambda_powertools/utilities/batch/sqs.py
index 38773a399dd..0a2e3fb7828 100644
--- a/aws_lambda_powertools/utilities/batch/sqs.py
+++ b/aws_lambda_powertools/utilities/batch/sqs.py
@@ -5,11 +5,13 @@
 """
 import logging
 import sys
-from typing import Callable, Dict, List, Optional, Tuple
+from typing import Callable, Dict, List, Optional, Tuple, cast
 
 import boto3
 from botocore.config import Config
 
+from aws_lambda_powertools.utilities.data_classes.sqs_event import SQSRecord
+
 from ...middleware_factory import lambda_handler_decorator
 from .base import BasePartialProcessor
 from .exceptions import SQSBatchProcessingError
@@ -84,11 +86,14 @@ def _get_queue_url(self) -> Optional[str]:
         *_, account_id, queue_name = self.records[0]["eventSourceARN"].split(":")
         return f"{self.client._endpoint.host}/{account_id}/{queue_name}"
 
-    def _get_entries_to_clean(self) -> List:
+    def _get_entries_to_clean(self) -> List[Dict[str, str]]:
         """
         Format messages to use in batch deletion
         """
-        return [{"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]} for msg in self.success_messages]
+        return [
+            {"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]}
+            for msg in cast(List[SQSRecord], self.success_messages)
+        ]
 
     def _process_record(self, record) -> Tuple:
         """
diff --git a/aws_lambda_powertools/utilities/idempotency/idempotency.py b/aws_lambda_powertools/utilities/idempotency/idempotency.py
index 42b8052fd32..4a7d8e71e1d 100644
--- a/aws_lambda_powertools/utilities/idempotency/idempotency.py
+++ b/aws_lambda_powertools/utilities/idempotency/idempotency.py
@@ -112,7 +112,7 @@ def process_order(customer_id: str, order: dict, **kwargs):
             return {"StatusCode": 200}
     """
 
-    if function is None:
+    if not function:
         return cast(
             AnyCallableT,
             functools.partial(
@@ -132,7 +132,7 @@ def decorate(*args, **kwargs):
 
         payload = kwargs.get(data_keyword_argument)
 
-        if payload is None:
+        if not payload:
             raise RuntimeError(
                 f"Unable to extract '{data_keyword_argument}' from keyword arguments."
                 f" Ensure this exists in your function's signature as well as the caller used it as a keyword argument"
diff --git a/aws_lambda_powertools/utilities/idempotency/persistence/base.py b/aws_lambda_powertools/utilities/idempotency/persistence/base.py
index b07662e6432..78262919f58 100644
--- a/aws_lambda_powertools/utilities/idempotency/persistence/base.py
+++ b/aws_lambda_powertools/utilities/idempotency/persistence/base.py
@@ -40,7 +40,7 @@ def __init__(
         idempotency_key,
         status: str = "",
         expiry_timestamp: Optional[int] = None,
-        response_data: Optional[str] = "",
+        response_data: str = "",
         payload_hash: Optional[str] = None,
     ) -> None:
         """
@@ -279,14 +279,14 @@ def _save_to_cache(self, data_record: DataRecord):
         -------
 
         """
-        if not self.use_local_cache:
+        if not self.use_local_cache or self._cache is None:
             return
         if data_record.status == STATUS_CONSTANTS["INPROGRESS"]:
             return
         self._cache[data_record.idempotency_key] = data_record
 
     def _retrieve_from_cache(self, idempotency_key: str):
-        if not self.use_local_cache:
+        if not self.use_local_cache or self._cache is None:
             return
         cached_record = self._cache.get(key=idempotency_key)
         if cached_record:
@@ -296,7 +296,7 @@ def _retrieve_from_cache(self, idempotency_key: str):
             self._delete_from_cache(idempotency_key=idempotency_key)
 
     def _delete_from_cache(self, idempotency_key: str):
-        if not self.use_local_cache:
+        if not self.use_local_cache or self._cache is None:
             return
         if idempotency_key in self._cache:
             del self._cache[idempotency_key]
diff --git a/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py b/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
index 8a470c0f910..228188dd136 100644
--- a/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
+++ b/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
@@ -130,7 +130,7 @@ def _item_to_data_record(self, item: Dict[str, Any]) -> DataRecord:
             idempotency_key=item[self.key_attr],
             status=item[self.status_attr],
             expiry_timestamp=item[self.expiry_attr],
-            response_data=item.get(self.data_attr),
+            response_data=item.get(self.data_attr, ""),
             payload_hash=item.get(self.validation_key_attr),
         )
 
diff --git a/aws_lambda_powertools/utilities/parameters/base.py b/aws_lambda_powertools/utilities/parameters/base.py
index b059a3b2483..383c72cfeab 100644
--- a/aws_lambda_powertools/utilities/parameters/base.py
+++ b/aws_lambda_powertools/utilities/parameters/base.py
@@ -15,6 +15,7 @@
 ExpirableValue = namedtuple("ExpirableValue", ["value", "ttl"])
 # These providers will be dynamically initialized on first use of the helper functions
 DEFAULT_PROVIDERS: Dict[str, Any] = {}
+MULTIPLE_VALUES_TYPE: Union[Dict[str, str], Dict[str, dict], Dict[str, bytes], Dict[str, None]]
 TRANSFORM_METHOD_JSON = "json"
 TRANSFORM_METHOD_BINARY = "binary"
 SUPPORTED_TRANSFORM_METHODS = [TRANSFORM_METHOD_JSON, TRANSFORM_METHOD_BINARY]
@@ -44,7 +45,7 @@ def get(
         transform: Optional[str] = None,
         force_fetch: bool = False,
         **sdk_options,
-    ) -> Union[str, list, dict, bytes]:
+    ) -> Optional[Union[str, dict, bytes]]:
         """
         Retrieve a parameter value or return the cached value
 
@@ -81,6 +82,7 @@ def get(
         # of supported transform is small and the probability that a given
         # parameter will always be used in a specific transform, this should be
         # an acceptable tradeoff.
+        value: Optional[Union[str, bytes, dict]] = None
         key = (name, transform)
 
         if not force_fetch and self._has_not_expired(key):
@@ -92,12 +94,12 @@ def get(
         except Exception as exc:
             raise GetParameterError(str(exc))
 
-        if transform is not None:
+        if transform:
             if isinstance(value, bytes):
                 value = value.decode("utf-8")
             value = transform_value(value, transform)
-
-        self.store[key] = ExpirableValue(value, datetime.now() + timedelta(seconds=max_age))
+            if value:
+                self.store[key] = ExpirableValue(value, datetime.now() + timedelta(seconds=max_age))
 
         return value
 
@@ -146,26 +148,25 @@ def get_multiple(
         TransformParameterError
             When the parameter provider fails to transform a parameter value.
         """
-
         key = (path, transform)
 
         if not force_fetch and self._has_not_expired(key):
             return self.store[key].value
 
         try:
-            values: Dict[str, Union[str, bytes, dict, None]] = self._get_multiple(path, **sdk_options)
+            values = self._get_multiple(path, **sdk_options)
         # Encapsulate all errors into a generic GetParameterError
         except Exception as exc:
             raise GetParameterError(str(exc))
 
-        if transform is not None:
-            for (key, value) in values.items():
-                _transform = get_transform_method(key, transform)
-                if _transform is None:
+        if transform:
+            transformed_values: dict = {}
+            for (item, value) in values.items():
+                _transform = get_transform_method(item, transform)
+                if not _transform:
                     continue
-
-                values[key] = transform_value(value, _transform, raise_on_transform_error)
-
+                transformed_values[item] = transform_value(value, _transform, raise_on_transform_error)
+            values.update(transformed_values)
         self.store[key] = ExpirableValue(values, datetime.now() + timedelta(seconds=max_age))
 
         return values
@@ -217,7 +218,9 @@ def get_transform_method(key: str, transform: Optional[str] = None) -> Optional[
     return None
 
 
-def transform_value(value: str, transform: str, raise_on_transform_error: bool = True) -> Union[dict, bytes, None]:
+def transform_value(
+    value: str, transform: str, raise_on_transform_error: Optional[bool] = True
+) -> Optional[Union[dict, bytes]]:
     """
     Apply a transform to a value
 
diff --git a/aws_lambda_powertools/utilities/parameters/ssm.py b/aws_lambda_powertools/utilities/parameters/ssm.py
index 4cbb16354c7..c71e30b2415 100644
--- a/aws_lambda_powertools/utilities/parameters/ssm.py
+++ b/aws_lambda_powertools/utilities/parameters/ssm.py
@@ -95,7 +95,7 @@ def get(
         decrypt: bool = False,
         force_fetch: bool = False,
         **sdk_options
-    ) -> Union[str, list, dict, bytes]:
+    ) -> Optional[Union[str, dict, bytes]]:
         """
         Retrieve a parameter value or return the cached value
 
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/apigw.py b/aws_lambda_powertools/utilities/parser/envelopes/apigw.py
index 6b74a3037e9..a9af93e9b9c 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/apigw.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/apigw.py
@@ -27,6 +27,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
             Parsed detail payload with model provided
         """
         logger.debug(f"Parsing incoming data with Api Gateway model {APIGatewayProxyEventModel}")
-        parsed_envelope = APIGatewayProxyEventModel.parse_obj(data)
+        parsed_envelope: APIGatewayProxyEventModel = APIGatewayProxyEventModel.parse_obj(data)
         logger.debug(f"Parsing event payload in `detail` with {model}")
         return self._parse(data=parsed_envelope.body, model=model)
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/apigwv2.py b/aws_lambda_powertools/utilities/parser/envelopes/apigwv2.py
index a627e4da0e5..336645a2b73 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/apigwv2.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/apigwv2.py
@@ -27,6 +27,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
             Parsed detail payload with model provided
         """
         logger.debug(f"Parsing incoming data with Api Gateway model V2 {APIGatewayProxyEventV2Model}")
-        parsed_envelope = APIGatewayProxyEventV2Model.parse_obj(data)
+        parsed_envelope: APIGatewayProxyEventV2Model = APIGatewayProxyEventV2Model.parse_obj(data)
         logger.debug(f"Parsing event payload in `detail` with {model}")
         return self._parse(data=parsed_envelope.body, model=model)
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/event_bridge.py b/aws_lambda_powertools/utilities/parser/envelopes/event_bridge.py
index ad1df09a65e..239bfd72025 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/event_bridge.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/event_bridge.py
@@ -27,6 +27,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
             Parsed detail payload with model provided
         """
         logger.debug(f"Parsing incoming data with EventBridge model {EventBridgeModel}")
-        parsed_envelope = EventBridgeModel.parse_obj(data)
+        parsed_envelope: EventBridgeModel = EventBridgeModel.parse_obj(data)
         logger.debug(f"Parsing event payload in `detail` with {model}")
         return self._parse(data=parsed_envelope.detail, model=model)
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/sns.py b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
index d4fa7c2f663..ada279fb5f5 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/sns.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
@@ -69,6 +69,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         parsed_envelope = SqsModel.parse_obj(data)
         output = []
         for record in parsed_envelope.Records:
-            sns_notification = SnsNotificationModel.parse_raw(record.body)
+            sns_notification: SnsNotificationModel = SnsNotificationModel.parse_raw(record.body)
             output.append(self._parse(data=sns_notification.Message, model=model))
         return output
diff --git a/aws_lambda_powertools/utilities/parser/models/alb.py b/aws_lambda_powertools/utilities/parser/models/alb.py
index 1112d0c04e4..e4cbd38f2fb 100644
--- a/aws_lambda_powertools/utilities/parser/models/alb.py
+++ b/aws_lambda_powertools/utilities/parser/models/alb.py
@@ -1,4 +1,4 @@
-from typing import Dict, Union
+from typing import Dict, Generic, Union
 
 from pydantic import BaseModel
 
@@ -13,7 +13,7 @@ class AlbRequestContext(BaseModel):
     elb: AlbRequestContextData
 
 
-class AlbModel(BaseModel):
+class AlbModel(BaseModel, Generic[Model]):
     httpMethod: str
     path: str
     body: Union[str, Model]
diff --git a/aws_lambda_powertools/utilities/parser/models/apigw.py b/aws_lambda_powertools/utilities/parser/models/apigw.py
index ce519b8e0e3..e5dab8334a7 100644
--- a/aws_lambda_powertools/utilities/parser/models/apigw.py
+++ b/aws_lambda_powertools/utilities/parser/models/apigw.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel, root_validator
 from pydantic.networks import IPvAnyNetwork
@@ -76,7 +76,7 @@ def check_message_id(cls, values):
         return values
 
 
-class APIGatewayProxyEventModel(BaseModel):
+class APIGatewayProxyEventModel(BaseModel, Generic[Model]):
     version: Optional[str]
     resource: str
     path: str
diff --git a/aws_lambda_powertools/utilities/parser/models/apigwv2.py b/aws_lambda_powertools/utilities/parser/models/apigwv2.py
index ddaf2d7ef82..7c64f065d07 100644
--- a/aws_lambda_powertools/utilities/parser/models/apigwv2.py
+++ b/aws_lambda_powertools/utilities/parser/models/apigwv2.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel, Field
 from pydantic.networks import IPvAnyNetwork
@@ -56,7 +56,7 @@ class RequestContextV2(BaseModel):
     http: RequestContextV2Http
 
 
-class APIGatewayProxyEventV2Model(BaseModel):
+class APIGatewayProxyEventV2Model(BaseModel, Generic[Model]):
     version: str
     routeKey: str
     rawPath: str
diff --git a/aws_lambda_powertools/utilities/parser/models/cloudwatch.py b/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
index 9b954ec3b13..31703c6810b 100644
--- a/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
+++ b/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
@@ -3,7 +3,7 @@
 import logging
 import zlib
 from datetime import datetime
-from typing import List, Union
+from typing import Generic, List, Union
 
 from pydantic import BaseModel, Field, validator
 
@@ -12,7 +12,7 @@
 logger = logging.getLogger(__name__)
 
 
-class CloudWatchLogsLogEvent(BaseModel):
+class CloudWatchLogsLogEvent(BaseModel, Generic[Model]):
     id: str  # noqa AA03 VNE003
     timestamp: datetime
     message: Union[str, Model]
diff --git a/aws_lambda_powertools/utilities/parser/models/dynamodb.py b/aws_lambda_powertools/utilities/parser/models/dynamodb.py
index fe7514bada0..0b826935242 100644
--- a/aws_lambda_powertools/utilities/parser/models/dynamodb.py
+++ b/aws_lambda_powertools/utilities/parser/models/dynamodb.py
@@ -1,12 +1,12 @@
 from datetime import date
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel
 
 from aws_lambda_powertools.utilities.parser.types import Literal, Model
 
 
-class DynamoDBStreamChangedRecordModel(BaseModel):
+class DynamoDBStreamChangedRecordModel(BaseModel, Generic[Model]):
     ApproximateCreationDateTime: Optional[date]
     Keys: Dict[str, Dict[str, Any]]
     NewImage: Optional[Union[Dict[str, Any], Model]]
diff --git a/aws_lambda_powertools/utilities/parser/models/event_bridge.py b/aws_lambda_powertools/utilities/parser/models/event_bridge.py
index f98a263c680..d0e02831075 100644
--- a/aws_lambda_powertools/utilities/parser/models/event_bridge.py
+++ b/aws_lambda_powertools/utilities/parser/models/event_bridge.py
@@ -1,12 +1,12 @@
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel, Field
 
 from aws_lambda_powertools.utilities.parser.types import Model
 
 
-class EventBridgeModel(BaseModel):
+class EventBridgeModel(BaseModel, Generic[Model]):
     version: str
     id: str  # noqa: A003,VNE003
     source: str
diff --git a/aws_lambda_powertools/utilities/parser/models/kinesis.py b/aws_lambda_powertools/utilities/parser/models/kinesis.py
index 1c7c31c97b4..dbc413eedcc 100644
--- a/aws_lambda_powertools/utilities/parser/models/kinesis.py
+++ b/aws_lambda_powertools/utilities/parser/models/kinesis.py
@@ -1,7 +1,7 @@
 import base64
 import logging
 from binascii import Error as BinAsciiError
-from typing import List, Union
+from typing import Generic, List, Union
 
 from pydantic import BaseModel, validator
 
@@ -10,7 +10,7 @@
 logger = logging.getLogger(__name__)
 
 
-class KinesisDataStreamRecordPayload(BaseModel):
+class KinesisDataStreamRecordPayload(BaseModel, Generic[Model]):
     kinesisSchemaVersion: str
     partitionKey: str
     sequenceNumber: str
diff --git a/aws_lambda_powertools/utilities/parser/models/s3_object_event.py b/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
index 778786bc8cb..0ded5947b2c 100644
--- a/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
+++ b/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
@@ -1,4 +1,4 @@
-from typing import Dict, Optional, Union
+from typing import Dict, Generic, Optional, Union
 
 from pydantic import BaseModel, HttpUrl
 
@@ -11,7 +11,7 @@ class S3ObjectContext(BaseModel):
     outputToken: str
 
 
-class S3ObjectConfiguration(BaseModel):
+class S3ObjectConfiguration(BaseModel, Generic[Model]):
     accessPointArn: str
     supportingAccessPointArn: str
     payload: Union[str, Model]
diff --git a/aws_lambda_powertools/utilities/parser/models/sns.py b/aws_lambda_powertools/utilities/parser/models/sns.py
index cdcd9549a98..5fe9813cd04 100644
--- a/aws_lambda_powertools/utilities/parser/models/sns.py
+++ b/aws_lambda_powertools/utilities/parser/models/sns.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from typing import Dict, List, Optional, Union
+from typing import Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel, root_validator
 from pydantic.networks import HttpUrl
@@ -12,7 +12,7 @@ class SnsMsgAttributeModel(BaseModel):
     Value: str
 
 
-class SnsNotificationModel(BaseModel):
+class SnsNotificationModel(BaseModel, Generic[Model]):
     Subject: Optional[str]
     TopicArn: str
     UnsubscribeUrl: HttpUrl
diff --git a/aws_lambda_powertools/utilities/parser/models/sqs.py b/aws_lambda_powertools/utilities/parser/models/sqs.py
index 47871ab8840..cbe3d523bb4 100644
--- a/aws_lambda_powertools/utilities/parser/models/sqs.py
+++ b/aws_lambda_powertools/utilities/parser/models/sqs.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from typing import Dict, List, Optional, Union
+from typing import Dict, Generic, List, Optional, Union
 
 from pydantic import BaseModel
 
@@ -49,7 +49,7 @@ class SqsMsgAttributeModel(BaseModel):
     #     return values # noqa: E800
 
 
-class SqsRecordModel(BaseModel):
+class SqsRecordModel(BaseModel, Generic[Model]):
     messageId: str
     receiptHandle: str
     body: Union[str, Model]

From 0c55c978220921fb5729ae0b2e90b701d3600552 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Sun, 16 Jan 2022 21:48:38 +0100
Subject: [PATCH 02/12] Silent overwide method error

Since any change to this method spec may be breaking to users and we cannot also move get method declaration in Base class we need to silent it and accept potential risk
---
 aws_lambda_powertools/utilities/parameters/ssm.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/aws_lambda_powertools/utilities/parameters/ssm.py b/aws_lambda_powertools/utilities/parameters/ssm.py
index c71e30b2415..5839fbdffd9 100644
--- a/aws_lambda_powertools/utilities/parameters/ssm.py
+++ b/aws_lambda_powertools/utilities/parameters/ssm.py
@@ -87,7 +87,7 @@ def __init__(self, config: Optional[Config] = None, boto3_session: Optional[boto
 
         super().__init__()
 
-    def get(
+    def get(  # type: ignore[override]
         self,
         name: str,
         max_age: int = DEFAULT_MAX_AGE_SECS,

From 8bcb3fdbe61426d32976a159f7041a98495d7c84 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Sun, 16 Jan 2022 23:04:37 +0100
Subject: [PATCH 03/12] Fix typing errors for python 3.6

---
 aws_lambda_powertools/event_handler/api_gateway.py |  6 +++---
 poetry.lock                                        | 14 +++++++++++++-
 pyproject.toml                                     |  1 +
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/aws_lambda_powertools/event_handler/api_gateway.py b/aws_lambda_powertools/event_handler/api_gateway.py
index 5017597c0f1..f423f1291fa 100644
--- a/aws_lambda_powertools/event_handler/api_gateway.py
+++ b/aws_lambda_powertools/event_handler/api_gateway.py
@@ -10,7 +10,7 @@
 from enum import Enum
 from functools import partial
 from http import HTTPStatus
-from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Type, Union
+from typing import Any, Callable, Dict, List, Match, Optional, Pattern, Set, Tuple, Type, Union
 
 from aws_lambda_powertools.event_handler import content_types
 from aws_lambda_powertools.event_handler.exceptions import NotFoundError, ServiceError
@@ -167,7 +167,7 @@ class Route:
     """Internally used Route Configuration"""
 
     def __init__(
-        self, method: str, rule: Any, func: Callable, cors: bool, compress: bool, cache_control: Optional[str]
+        self, method: str, rule: Pattern, func: Callable, cors: bool, compress: bool, cache_control: Optional[str]
     ):
         self.method = method.upper()
         self.rule = rule
@@ -555,7 +555,7 @@ def _resolve(self) -> ResponseBuilder:
         for route in self._routes:
             if method != route.method:
                 continue
-            match_results: Optional[re.Match] = route.rule.match(path)
+            match_results: Optional[Match] = route.rule.match(path)
             if match_results:
                 logger.debug("Found a registered route. Calling function")
                 return self._call_route(route, match_results.groupdict())  # pass fn args
diff --git a/poetry.lock b/poetry.lock
index 1ed434d9afa..09e940fec8e 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -985,6 +985,14 @@ category = "dev"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "types-dataclasses"
+version = "0.6.4"
+description = "Typing stubs for dataclasses"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "typing-extensions"
 version = "4.0.1"
@@ -1056,7 +1064,7 @@ pydantic = ["pydantic", "email-validator"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6.2"
-content-hash = "c1df73741840dc9ee5e8dbbf6bfa02e09d3c84f53318e3e36cba9b30f6f2d2e4"
+content-hash = "a263c73ed245c75e0d4472b672bee8548ef1a1d5e4d9c092b57f4d8506835204"
 
 [metadata.files]
 atomicwrites = [
@@ -1625,6 +1633,10 @@ typed-ast = [
     {file = "typed_ast-1.4.3-cp39-cp39-win_amd64.whl", hash = "sha256:9c6d1a54552b5330bc657b7ef0eae25d00ba7ffe85d9ea8ae6540d2197a3788c"},
     {file = "typed_ast-1.4.3.tar.gz", hash = "sha256:fb1bbeac803adea29cedd70781399c99138358c26d05fcbd23c13016b7f5ec65"},
 ]
+types-dataclasses = [
+    {file = "types-dataclasses-0.6.4.tar.gz", hash = "sha256:2f7ab6c565cf05cc7f27f31a4c2fcc803384e319aab292807b857ddf1473429f"},
+    {file = "types_dataclasses-0.6.4-py3-none-any.whl", hash = "sha256:fef6ed4742ca27996530c6d549cd704772a4a86e4781841c9bb387001e369ec3"},
+]
 typing-extensions = [
     {file = "typing_extensions-4.0.1-py3-none-any.whl", hash = "sha256:7f001e5ac290a0c0401508864c7ec868be4e701886d5b573a9528ed3973d9d3b"},
     {file = "typing_extensions-4.0.1.tar.gz", hash = "sha256:4ca091dea149f945ec56afb48dae714f21e8692ef22a395223bcd328961b6a0e"},
diff --git a/pyproject.toml b/pyproject.toml
index bdda4cdaa5e..7c5e79292c4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -54,6 +54,7 @@ mkdocs-material = "^7.3.6"
 mkdocs-git-revision-date-plugin = "^0.3.1"
 mike = "^0.6.0"
 mypy = "^0.931"
+types-dataclasses = "^0.6.4"
 
 
 [tool.poetry.extras]

From 0196883410bf4fadeb1ca27f3f331ec6fbaffbe4 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Tue, 18 Jan 2022 09:19:58 +0100
Subject: [PATCH 04/12] Use BaseModel directly instead of TypeVar to avoid
 python3.6 limitations

---
 .../utilities/parser/envelopes/kinesis.py              |  5 +++--
 .../utilities/parser/envelopes/sns.py                  |  4 ++--
 aws_lambda_powertools/utilities/parser/models/alb.py   |  8 +++-----
 aws_lambda_powertools/utilities/parser/models/apigw.py |  8 ++++----
 .../utilities/parser/models/apigwv2.py                 |  8 ++++----
 .../utilities/parser/models/cloudwatch.py              |  8 +++-----
 .../utilities/parser/models/dynamodb.py                | 10 +++++-----
 .../utilities/parser/models/event_bridge.py            |  8 +++-----
 .../utilities/parser/models/kinesis.py                 |  8 ++++----
 .../utilities/parser/models/s3_object_event.py         |  8 +++-----
 aws_lambda_powertools/utilities/parser/models/sns.py   | 10 ++++++----
 aws_lambda_powertools/utilities/parser/models/sqs.py   |  8 ++++----
 12 files changed, 44 insertions(+), 49 deletions(-)

diff --git a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
index 9db8e4450f2..88ae65f6e12 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
@@ -1,5 +1,5 @@
 import logging
-from typing import Any, Dict, List, Optional, Type, Union
+from typing import Any, Dict, List, Optional, Type, Union, cast
 
 from ..models import KinesisDataStreamModel
 from ..types import Model
@@ -38,5 +38,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         parsed_envelope: KinesisDataStreamModel = KinesisDataStreamModel.parse_obj(data)
         logger.debug(f"Parsing Kinesis records in `body` with {model}")
         return [
-            self._parse(data=record.kinesis.data.decode("utf-8"), model=model) for record in parsed_envelope.Records
+            self._parse(data=cast(bytes, record.kinesis.data).decode("utf-8"), model=model)
+            for record in parsed_envelope.Records
         ]
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/sns.py b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
index ada279fb5f5..dafbf755d8c 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/sns.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
@@ -1,5 +1,5 @@
 import logging
-from typing import Any, Dict, List, Optional, Type, Union
+from typing import Any, Dict, List, Optional, Type, Union, cast
 
 from ..models import SnsModel, SnsNotificationModel, SqsModel
 from ..types import Model
@@ -69,6 +69,6 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         parsed_envelope = SqsModel.parse_obj(data)
         output = []
         for record in parsed_envelope.Records:
-            sns_notification: SnsNotificationModel = SnsNotificationModel.parse_raw(record.body)
+            sns_notification: SnsNotificationModel = SnsNotificationModel.parse_raw(cast(str, record.body))
             output.append(self._parse(data=sns_notification.Message, model=model))
         return output
diff --git a/aws_lambda_powertools/utilities/parser/models/alb.py b/aws_lambda_powertools/utilities/parser/models/alb.py
index e4cbd38f2fb..d903e9f0fd8 100644
--- a/aws_lambda_powertools/utilities/parser/models/alb.py
+++ b/aws_lambda_powertools/utilities/parser/models/alb.py
@@ -1,9 +1,7 @@
-from typing import Dict, Generic, Union
+from typing import Dict, Type, Union
 
 from pydantic import BaseModel
 
-from aws_lambda_powertools.utilities.parser.types import Model
-
 
 class AlbRequestContextData(BaseModel):
     targetGroupArn: str
@@ -13,10 +11,10 @@ class AlbRequestContext(BaseModel):
     elb: AlbRequestContextData
 
 
-class AlbModel(BaseModel, Generic[Model]):
+class AlbModel(BaseModel):
     httpMethod: str
     path: str
-    body: Union[str, Model]
+    body: Union[str, Type[BaseModel]]
     isBase64Encoded: bool
     headers: Dict[str, str]
     queryStringParameters: Dict[str, str]
diff --git a/aws_lambda_powertools/utilities/parser/models/apigw.py b/aws_lambda_powertools/utilities/parser/models/apigw.py
index e5dab8334a7..78b40cd2c0c 100644
--- a/aws_lambda_powertools/utilities/parser/models/apigw.py
+++ b/aws_lambda_powertools/utilities/parser/models/apigw.py
@@ -1,10 +1,10 @@
 from datetime import datetime
-from typing import Any, Dict, Generic, List, Optional, Union
+from typing import Any, Dict, List, Optional, Type, Union
 
 from pydantic import BaseModel, root_validator
 from pydantic.networks import IPvAnyNetwork
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 
 class ApiGatewayUserCertValidity(BaseModel):
@@ -76,7 +76,7 @@ def check_message_id(cls, values):
         return values
 
 
-class APIGatewayProxyEventModel(BaseModel, Generic[Model]):
+class APIGatewayProxyEventModel(BaseModel):
     version: Optional[str]
     resource: str
     path: str
@@ -89,4 +89,4 @@ class APIGatewayProxyEventModel(BaseModel, Generic[Model]):
     pathParameters: Optional[Dict[str, str]]
     stageVariables: Optional[Dict[str, str]]
     isBase64Encoded: bool
-    body: Optional[Union[str, Model]]
+    body: Optional[Union[str, Type[BaseModel]]]
diff --git a/aws_lambda_powertools/utilities/parser/models/apigwv2.py b/aws_lambda_powertools/utilities/parser/models/apigwv2.py
index 7c64f065d07..f97dad3bcb0 100644
--- a/aws_lambda_powertools/utilities/parser/models/apigwv2.py
+++ b/aws_lambda_powertools/utilities/parser/models/apigwv2.py
@@ -1,10 +1,10 @@
 from datetime import datetime
-from typing import Any, Dict, Generic, List, Optional, Union
+from typing import Any, Dict, List, Optional, Type, Union
 
 from pydantic import BaseModel, Field
 from pydantic.networks import IPvAnyNetwork
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 
 class RequestContextV2AuthorizerIamCognito(BaseModel):
@@ -56,7 +56,7 @@ class RequestContextV2(BaseModel):
     http: RequestContextV2Http
 
 
-class APIGatewayProxyEventV2Model(BaseModel, Generic[Model]):
+class APIGatewayProxyEventV2Model(BaseModel):
     version: str
     routeKey: str
     rawPath: str
@@ -67,5 +67,5 @@ class APIGatewayProxyEventV2Model(BaseModel, Generic[Model]):
     pathParameters: Optional[Dict[str, str]]
     stageVariables: Optional[Dict[str, str]]
     requestContext: RequestContextV2
-    body: Optional[Union[str, Model]]
+    body: Optional[Union[str, Type[BaseModel]]]
     isBase64Encoded: bool
diff --git a/aws_lambda_powertools/utilities/parser/models/cloudwatch.py b/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
index 31703c6810b..71e560276a4 100644
--- a/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
+++ b/aws_lambda_powertools/utilities/parser/models/cloudwatch.py
@@ -3,19 +3,17 @@
 import logging
 import zlib
 from datetime import datetime
-from typing import Generic, List, Union
+from typing import List, Type, Union
 
 from pydantic import BaseModel, Field, validator
 
-from aws_lambda_powertools.utilities.parser.types import Model
-
 logger = logging.getLogger(__name__)
 
 
-class CloudWatchLogsLogEvent(BaseModel, Generic[Model]):
+class CloudWatchLogsLogEvent(BaseModel):
     id: str  # noqa AA03 VNE003
     timestamp: datetime
-    message: Union[str, Model]
+    message: Union[str, Type[BaseModel]]
 
 
 class CloudWatchLogsDecode(BaseModel):
diff --git a/aws_lambda_powertools/utilities/parser/models/dynamodb.py b/aws_lambda_powertools/utilities/parser/models/dynamodb.py
index 0b826935242..772b8fb580f 100644
--- a/aws_lambda_powertools/utilities/parser/models/dynamodb.py
+++ b/aws_lambda_powertools/utilities/parser/models/dynamodb.py
@@ -1,16 +1,16 @@
 from datetime import date
-from typing import Any, Dict, Generic, List, Optional, Union
+from typing import Any, Dict, List, Optional, Type, Union
 
 from pydantic import BaseModel
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 
-class DynamoDBStreamChangedRecordModel(BaseModel, Generic[Model]):
+class DynamoDBStreamChangedRecordModel(BaseModel):
     ApproximateCreationDateTime: Optional[date]
     Keys: Dict[str, Dict[str, Any]]
-    NewImage: Optional[Union[Dict[str, Any], Model]]
-    OldImage: Optional[Union[Dict[str, Any], Model]]
+    NewImage: Optional[Union[Dict[str, Any], Type[BaseModel]]]
+    OldImage: Optional[Union[Dict[str, Any], Type[BaseModel]]]
     SequenceNumber: str
     SizeBytes: int
     StreamViewType: Literal["NEW_AND_OLD_IMAGES", "KEYS_ONLY", "NEW_IMAGE", "OLD_IMAGE"]
diff --git a/aws_lambda_powertools/utilities/parser/models/event_bridge.py b/aws_lambda_powertools/utilities/parser/models/event_bridge.py
index d0e02831075..68359f867bd 100644
--- a/aws_lambda_powertools/utilities/parser/models/event_bridge.py
+++ b/aws_lambda_powertools/utilities/parser/models/event_bridge.py
@@ -1,12 +1,10 @@
 from datetime import datetime
-from typing import Any, Dict, Generic, List, Optional, Union
+from typing import Any, Dict, List, Optional, Type, Union
 
 from pydantic import BaseModel, Field
 
-from aws_lambda_powertools.utilities.parser.types import Model
 
-
-class EventBridgeModel(BaseModel, Generic[Model]):
+class EventBridgeModel(BaseModel):
     version: str
     id: str  # noqa: A003,VNE003
     source: str
@@ -15,5 +13,5 @@ class EventBridgeModel(BaseModel, Generic[Model]):
     region: str
     resources: List[str]
     detail_type: str = Field(None, alias="detail-type")
-    detail: Union[Dict[str, Any], Model]
+    detail: Union[Dict[str, Any], Type[BaseModel]]
     replay_name: Optional[str] = Field(None, alias="replay-name")
diff --git a/aws_lambda_powertools/utilities/parser/models/kinesis.py b/aws_lambda_powertools/utilities/parser/models/kinesis.py
index dbc413eedcc..be868ca44ba 100644
--- a/aws_lambda_powertools/utilities/parser/models/kinesis.py
+++ b/aws_lambda_powertools/utilities/parser/models/kinesis.py
@@ -1,20 +1,20 @@
 import base64
 import logging
 from binascii import Error as BinAsciiError
-from typing import Generic, List, Union
+from typing import List, Type, Union
 
 from pydantic import BaseModel, validator
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 logger = logging.getLogger(__name__)
 
 
-class KinesisDataStreamRecordPayload(BaseModel, Generic[Model]):
+class KinesisDataStreamRecordPayload(BaseModel):
     kinesisSchemaVersion: str
     partitionKey: str
     sequenceNumber: str
-    data: Union[bytes, Model]  # base64 encoded str is parsed into bytes
+    data: Union[bytes, Type[BaseModel]]  # base64 encoded str is parsed into bytes
     approximateArrivalTimestamp: float
 
     @validator("data", pre=True, allow_reuse=True)
diff --git a/aws_lambda_powertools/utilities/parser/models/s3_object_event.py b/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
index 0ded5947b2c..ef59e9c2f98 100644
--- a/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
+++ b/aws_lambda_powertools/utilities/parser/models/s3_object_event.py
@@ -1,9 +1,7 @@
-from typing import Dict, Generic, Optional, Union
+from typing import Dict, Optional, Type, Union
 
 from pydantic import BaseModel, HttpUrl
 
-from aws_lambda_powertools.utilities.parser.types import Model
-
 
 class S3ObjectContext(BaseModel):
     inputS3Url: HttpUrl
@@ -11,10 +9,10 @@ class S3ObjectContext(BaseModel):
     outputToken: str
 
 
-class S3ObjectConfiguration(BaseModel, Generic[Model]):
+class S3ObjectConfiguration(BaseModel):
     accessPointArn: str
     supportingAccessPointArn: str
-    payload: Union[str, Model]
+    payload: Union[str, Type[BaseModel]]
 
 
 class S3ObjectUserRequest(BaseModel):
diff --git a/aws_lambda_powertools/utilities/parser/models/sns.py b/aws_lambda_powertools/utilities/parser/models/sns.py
index 5fe9813cd04..e329162e5c8 100644
--- a/aws_lambda_powertools/utilities/parser/models/sns.py
+++ b/aws_lambda_powertools/utilities/parser/models/sns.py
@@ -1,10 +1,12 @@
 from datetime import datetime
-from typing import Dict, Generic, List, Optional, Union
+from typing import Dict, List, Optional
+from typing import Type as TypingType
+from typing import Union
 
 from pydantic import BaseModel, root_validator
 from pydantic.networks import HttpUrl
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 
 class SnsMsgAttributeModel(BaseModel):
@@ -12,13 +14,13 @@ class SnsMsgAttributeModel(BaseModel):
     Value: str
 
 
-class SnsNotificationModel(BaseModel, Generic[Model]):
+class SnsNotificationModel(BaseModel):
     Subject: Optional[str]
     TopicArn: str
     UnsubscribeUrl: HttpUrl
     Type: Literal["Notification"]
     MessageAttributes: Optional[Dict[str, SnsMsgAttributeModel]]
-    Message: Union[str, Model]
+    Message: Union[str, TypingType[BaseModel]]
     MessageId: str
     SigningCertUrl: HttpUrl
     Signature: str
diff --git a/aws_lambda_powertools/utilities/parser/models/sqs.py b/aws_lambda_powertools/utilities/parser/models/sqs.py
index cbe3d523bb4..1d56c4f8e34 100644
--- a/aws_lambda_powertools/utilities/parser/models/sqs.py
+++ b/aws_lambda_powertools/utilities/parser/models/sqs.py
@@ -1,9 +1,9 @@
 from datetime import datetime
-from typing import Dict, Generic, List, Optional, Union
+from typing import Dict, List, Optional, Type, Union
 
 from pydantic import BaseModel
 
-from aws_lambda_powertools.utilities.parser.types import Literal, Model
+from aws_lambda_powertools.utilities.parser.types import Literal
 
 
 class SqsAttributesModel(BaseModel):
@@ -49,10 +49,10 @@ class SqsMsgAttributeModel(BaseModel):
     #     return values # noqa: E800
 
 
-class SqsRecordModel(BaseModel, Generic[Model]):
+class SqsRecordModel(BaseModel):
     messageId: str
     receiptHandle: str
-    body: Union[str, Model]
+    body: Union[str, Type[BaseModel]]
     attributes: SqsAttributesModel
     messageAttributes: Dict[str, SqsMsgAttributeModel]
     md5OfBody: str

From 862c67e1abe9ba5d301d0e545d44f9dbbb2644c2 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Thu, 27 Jan 2022 22:18:49 +0100
Subject: [PATCH 05/12] Apply PR suggestions

---
 aws_lambda_powertools/utilities/batch/sqs.py      | 11 +++++++----
 .../utilities/idempotency/persistence/base.py     | 15 +++++++--------
 .../utilities/idempotency/persistence/dynamodb.py |  2 +-
 aws_lambda_powertools/utilities/parameters/ssm.py |  2 ++
 .../utilities/parser/envelopes/kinesis.py         | 10 ++++++----
 .../utilities/parser/envelopes/sns.py             |  4 +++-
 mypy.ini                                          |  3 +++
 poetry.lock                                       | 14 +-------------
 pyproject.toml                                    |  1 -
 9 files changed, 30 insertions(+), 32 deletions(-)

diff --git a/aws_lambda_powertools/utilities/batch/sqs.py b/aws_lambda_powertools/utilities/batch/sqs.py
index 0a2e3fb7828..411e400615d 100644
--- a/aws_lambda_powertools/utilities/batch/sqs.py
+++ b/aws_lambda_powertools/utilities/batch/sqs.py
@@ -90,10 +90,13 @@ def _get_entries_to_clean(self) -> List[Dict[str, str]]:
         """
         Format messages to use in batch deletion
         """
-        return [
-            {"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]}
-            for msg in cast(List[SQSRecord], self.success_messages)
-        ]
+        entries = []
+        # success_messages has generic type of union of SQS, Dynamodb and Kinesis Streams records or Pydantic models.
+        # Here we get SQS Record only
+        messages = cast(List[SQSRecord], self.success_messages)
+        for msg in messages:
+            entries.append({"Id": msg["messageId"], "ReceiptHandle": msg["receiptHandle"]})
+        return entries
 
     def _process_record(self, record) -> Tuple:
         """
diff --git a/aws_lambda_powertools/utilities/idempotency/persistence/base.py b/aws_lambda_powertools/utilities/idempotency/persistence/base.py
index 78262919f58..e6ffea10de8 100644
--- a/aws_lambda_powertools/utilities/idempotency/persistence/base.py
+++ b/aws_lambda_powertools/utilities/idempotency/persistence/base.py
@@ -40,7 +40,7 @@ def __init__(
         idempotency_key,
         status: str = "",
         expiry_timestamp: Optional[int] = None,
-        response_data: str = "",
+        response_data: Optional[str] = "",
         payload_hash: Optional[str] = None,
     ) -> None:
         """
@@ -92,16 +92,16 @@ def status(self) -> str:
         else:
             raise IdempotencyInvalidStatusError(self._status)
 
-    def response_json_as_dict(self) -> dict:
+    def response_json_as_dict(self) -> Optional[dict]:
         """
         Get response data deserialized to python dict
 
         Returns
         -------
-        dict
+        Optional[dict]
             previous response data deserialized
         """
-        return json.loads(self.response_data)
+        return json.loads(self.response_data) if self.response_data else None
 
 
 class BasePersistenceLayer(ABC):
@@ -121,7 +121,6 @@ def __init__(self):
         self.raise_on_no_idempotency_key = False
         self.expires_after_seconds: int = 60 * 60  # 1 hour default
         self.use_local_cache = False
-        self._cache: Optional[LRUDict] = None
         self.hash_function = None
 
     def configure(self, config: IdempotencyConfig, function_name: Optional[str] = None) -> None:
@@ -279,14 +278,14 @@ def _save_to_cache(self, data_record: DataRecord):
         -------
 
         """
-        if not self.use_local_cache or self._cache is None:
+        if not self.use_local_cache:
             return
         if data_record.status == STATUS_CONSTANTS["INPROGRESS"]:
             return
         self._cache[data_record.idempotency_key] = data_record
 
     def _retrieve_from_cache(self, idempotency_key: str):
-        if not self.use_local_cache or self._cache is None:
+        if not self.use_local_cache:
             return
         cached_record = self._cache.get(key=idempotency_key)
         if cached_record:
@@ -296,7 +295,7 @@ def _retrieve_from_cache(self, idempotency_key: str):
             self._delete_from_cache(idempotency_key=idempotency_key)
 
     def _delete_from_cache(self, idempotency_key: str):
-        if not self.use_local_cache or self._cache is None:
+        if not self.use_local_cache:
             return
         if idempotency_key in self._cache:
             del self._cache[idempotency_key]
diff --git a/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py b/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
index 228188dd136..8a470c0f910 100644
--- a/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
+++ b/aws_lambda_powertools/utilities/idempotency/persistence/dynamodb.py
@@ -130,7 +130,7 @@ def _item_to_data_record(self, item: Dict[str, Any]) -> DataRecord:
             idempotency_key=item[self.key_attr],
             status=item[self.status_attr],
             expiry_timestamp=item[self.expiry_attr],
-            response_data=item.get(self.data_attr, ""),
+            response_data=item.get(self.data_attr),
             payload_hash=item.get(self.validation_key_attr),
         )
 
diff --git a/aws_lambda_powertools/utilities/parameters/ssm.py b/aws_lambda_powertools/utilities/parameters/ssm.py
index 5839fbdffd9..fd55e40a95f 100644
--- a/aws_lambda_powertools/utilities/parameters/ssm.py
+++ b/aws_lambda_powertools/utilities/parameters/ssm.py
@@ -87,6 +87,8 @@ def __init__(self, config: Optional[Config] = None, boto3_session: Optional[boto
 
         super().__init__()
 
+    # We break Liskov substitution principle due to differences in signatures of this method and superclass get method
+    # We ignore mypy error, as changes to the signature here or in a superclass is a breaking change to users
     def get(  # type: ignore[override]
         self,
         name: str,
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
index 88ae65f6e12..cede74c7a54 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
@@ -37,7 +37,9 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         logger.debug(f"Parsing incoming data with Kinesis model {KinesisDataStreamModel}")
         parsed_envelope: KinesisDataStreamModel = KinesisDataStreamModel.parse_obj(data)
         logger.debug(f"Parsing Kinesis records in `body` with {model}")
-        return [
-            self._parse(data=cast(bytes, record.kinesis.data).decode("utf-8"), model=model)
-            for record in parsed_envelope.Records
-        ]
+        models = []
+        for record in parsed_envelope.Records:
+            # We allow either AWS expected contract (bytes) or a custom Model, see #943
+            data = cast(bytes, record.kinesis.data)
+            models.append(self._parse(data=cast(bytes, record.kinesis.data).decode("utf-8"), model=model))
+        return models
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/sns.py b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
index dafbf755d8c..50b9d406c23 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/sns.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/sns.py
@@ -69,6 +69,8 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         parsed_envelope = SqsModel.parse_obj(data)
         output = []
         for record in parsed_envelope.Records:
-            sns_notification: SnsNotificationModel = SnsNotificationModel.parse_raw(cast(str, record.body))
+            # We allow either AWS expected contract (str) or a custom Model, see #943
+            body = cast(str, record.body)
+            sns_notification = SnsNotificationModel.parse_raw(body)
             output.append(self._parse(data=sns_notification.Message, model=model))
         return output
diff --git a/mypy.ini b/mypy.ini
index faf6014a54d..3061cc4a2d9 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -31,3 +31,6 @@ ignore_missing_imports = True
 
 [mypy-aws_xray_sdk.ext.aiohttp.client]
 ignore_missing_imports = True
+
+[mypy-dataclasses]
+ignore_missing_imports = True
\ No newline at end of file
diff --git a/poetry.lock b/poetry.lock
index 09e940fec8e..1ed434d9afa 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -985,14 +985,6 @@ category = "dev"
 optional = false
 python-versions = "*"
 
-[[package]]
-name = "types-dataclasses"
-version = "0.6.4"
-description = "Typing stubs for dataclasses"
-category = "dev"
-optional = false
-python-versions = "*"
-
 [[package]]
 name = "typing-extensions"
 version = "4.0.1"
@@ -1064,7 +1056,7 @@ pydantic = ["pydantic", "email-validator"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6.2"
-content-hash = "a263c73ed245c75e0d4472b672bee8548ef1a1d5e4d9c092b57f4d8506835204"
+content-hash = "c1df73741840dc9ee5e8dbbf6bfa02e09d3c84f53318e3e36cba9b30f6f2d2e4"
 
 [metadata.files]
 atomicwrites = [
@@ -1633,10 +1625,6 @@ typed-ast = [
     {file = "typed_ast-1.4.3-cp39-cp39-win_amd64.whl", hash = "sha256:9c6d1a54552b5330bc657b7ef0eae25d00ba7ffe85d9ea8ae6540d2197a3788c"},
     {file = "typed_ast-1.4.3.tar.gz", hash = "sha256:fb1bbeac803adea29cedd70781399c99138358c26d05fcbd23c13016b7f5ec65"},
 ]
-types-dataclasses = [
-    {file = "types-dataclasses-0.6.4.tar.gz", hash = "sha256:2f7ab6c565cf05cc7f27f31a4c2fcc803384e319aab292807b857ddf1473429f"},
-    {file = "types_dataclasses-0.6.4-py3-none-any.whl", hash = "sha256:fef6ed4742ca27996530c6d549cd704772a4a86e4781841c9bb387001e369ec3"},
-]
 typing-extensions = [
     {file = "typing_extensions-4.0.1-py3-none-any.whl", hash = "sha256:7f001e5ac290a0c0401508864c7ec868be4e701886d5b573a9528ed3973d9d3b"},
     {file = "typing_extensions-4.0.1.tar.gz", hash = "sha256:4ca091dea149f945ec56afb48dae714f21e8692ef22a395223bcd328961b6a0e"},
diff --git a/pyproject.toml b/pyproject.toml
index 7c5e79292c4..bdda4cdaa5e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -54,7 +54,6 @@ mkdocs-material = "^7.3.6"
 mkdocs-git-revision-date-plugin = "^0.3.1"
 mike = "^0.6.0"
 mypy = "^0.931"
-types-dataclasses = "^0.6.4"
 
 
 [tool.poetry.extras]

From a82e9595f91b59939b193024c120f4f0892c9b92 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Thu, 27 Jan 2022 22:53:44 +0100
Subject: [PATCH 06/12] Add missing tests

---
 .../idempotency/test_idempotency.py           | 23 +++++++++++++++++++
 tests/functional/test_metrics.py              | 20 ++++++++++++++++
 2 files changed, 43 insertions(+)

diff --git a/tests/functional/idempotency/test_idempotency.py b/tests/functional/idempotency/test_idempotency.py
index 0732f1d58b1..ab915931a70 100644
--- a/tests/functional/idempotency/test_idempotency.py
+++ b/tests/functional/idempotency/test_idempotency.py
@@ -648,6 +648,29 @@ def test_data_record_invalid_status_value():
     assert e.value.args[0] == "UNSUPPORTED_STATUS"
 
 
+def test_data_record_json_to_dict_mapping():
+    # GIVEN a data record with status "COMPLETED" and provided response data
+    data_record = DataRecord(
+        "key", status="INPROGRESS", response_data='{"body": "execution finished","statusCode": "200"}'
+    )
+
+    # WHEN translating response data to dictionary
+    response_data = data_record.response_json_as_dict()
+
+    # THEN return dictionary
+    assert isinstance(response_data, dict)
+
+
+def test_data_record_json_to_dict_mapping_when_response_data_none():
+    # GIVEN a data record with status "INPROGRESS" and not set response data
+    data_record = DataRecord("key", status="INPROGRESS", response_data=None)
+    # WHEN translating response data to dictionary
+    response_data = data_record.response_json_as_dict()
+
+    # THEN return null value
+    assert response_data is None
+
+
 @pytest.mark.parametrize("idempotency_config", [{"use_local_cache": True}], indirect=True)
 def test_in_progress_never_saved_to_cache(
     idempotency_config: IdempotencyConfig, persistence_store: DynamoDBPersistenceLayer
diff --git a/tests/functional/test_metrics.py b/tests/functional/test_metrics.py
index ae160c65d87..9d03a25e8b6 100644
--- a/tests/functional/test_metrics.py
+++ b/tests/functional/test_metrics.py
@@ -493,9 +493,29 @@ def lambda_handler(evt, context):
 
     output = capture_metrics_output(capsys)
 
+    # THEN ColdStart metric and function_name and service dimension should be logged
+    assert output["ColdStart"] == [1.0]
+    assert output["function_name"] == "example_fn"
+    assert output['service'] == service
+
+def test_log_metrics_capture_cold_start_metric_no_service(capsys, namespace):
+    # GIVEN Metrics is initialized without service
+    my_metrics = Metrics(namespace=namespace)
+
+    # WHEN log_metrics is used with capture_cold_start_metric
+    @my_metrics.log_metrics(capture_cold_start_metric=True)
+    def lambda_handler(evt, context):
+        pass
+
+    LambdaContext = namedtuple("LambdaContext", "function_name")
+    lambda_handler({}, LambdaContext("example_fn"))
+
+    output = capture_metrics_output(capsys)
+
     # THEN ColdStart metric and function_name dimension should be logged
     assert output["ColdStart"] == [1.0]
     assert output["function_name"] == "example_fn"
+    assert output.get('service') is None
 
 
 def test_emit_cold_start_metric_only_once(capsys, namespace, service, metric):

From 521bf92233063abae152666ebd7728481f1992ac Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Thu, 27 Jan 2022 23:23:19 +0100
Subject: [PATCH 07/12] Remove not needed value check in parameter base

---
 aws_lambda_powertools/utilities/parameters/base.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/aws_lambda_powertools/utilities/parameters/base.py b/aws_lambda_powertools/utilities/parameters/base.py
index 383c72cfeab..26162951eaf 100644
--- a/aws_lambda_powertools/utilities/parameters/base.py
+++ b/aws_lambda_powertools/utilities/parameters/base.py
@@ -98,8 +98,8 @@ def get(
             if isinstance(value, bytes):
                 value = value.decode("utf-8")
             value = transform_value(value, transform)
-            if value:
-                self.store[key] = ExpirableValue(value, datetime.now() + timedelta(seconds=max_age))
+
+        self.store[key] = ExpirableValue(value, datetime.now() + timedelta(seconds=max_age))
 
         return value
 

From 8831b4b9ea08bee173a806697818232c9fad0c37 Mon Sep 17 00:00:00 2001
From: Michal Ploski <mploski@amazon.com>
Date: Thu, 27 Jan 2022 23:36:02 +0100
Subject: [PATCH 08/12] Cleanup unused variable and repeated code

---
 aws_lambda_powertools/utilities/parameters/base.py          | 1 -
 aws_lambda_powertools/utilities/parser/envelopes/kinesis.py | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/aws_lambda_powertools/utilities/parameters/base.py b/aws_lambda_powertools/utilities/parameters/base.py
index 26162951eaf..7e8588eb895 100644
--- a/aws_lambda_powertools/utilities/parameters/base.py
+++ b/aws_lambda_powertools/utilities/parameters/base.py
@@ -15,7 +15,6 @@
 ExpirableValue = namedtuple("ExpirableValue", ["value", "ttl"])
 # These providers will be dynamically initialized on first use of the helper functions
 DEFAULT_PROVIDERS: Dict[str, Any] = {}
-MULTIPLE_VALUES_TYPE: Union[Dict[str, str], Dict[str, dict], Dict[str, bytes], Dict[str, None]]
 TRANSFORM_METHOD_JSON = "json"
 TRANSFORM_METHOD_BINARY = "binary"
 SUPPORTED_TRANSFORM_METHODS = [TRANSFORM_METHOD_JSON, TRANSFORM_METHOD_BINARY]
diff --git a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
index cede74c7a54..9ff221a7b7b 100644
--- a/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
+++ b/aws_lambda_powertools/utilities/parser/envelopes/kinesis.py
@@ -41,5 +41,5 @@ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model])
         for record in parsed_envelope.Records:
             # We allow either AWS expected contract (bytes) or a custom Model, see #943
             data = cast(bytes, record.kinesis.data)
-            models.append(self._parse(data=cast(bytes, record.kinesis.data).decode("utf-8"), model=model))
+            models.append(self._parse(data=data.decode("utf-8"), model=model))
         return models

From e707edd4433486d5e6349c932725047fd15690c7 Mon Sep 17 00:00:00 2001
From: Heitor Lessa <heitor.lessa@hotmail.com>
Date: Mon, 31 Jan 2022 14:17:38 +0100
Subject: [PATCH 09/12] chore: typo in test comment

---
 tests/functional/idempotency/test_idempotency.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/functional/idempotency/test_idempotency.py b/tests/functional/idempotency/test_idempotency.py
index ab915931a70..5b76cda0475 100644
--- a/tests/functional/idempotency/test_idempotency.py
+++ b/tests/functional/idempotency/test_idempotency.py
@@ -649,7 +649,7 @@ def test_data_record_invalid_status_value():
 
 
 def test_data_record_json_to_dict_mapping():
-    # GIVEN a data record with status "COMPLETED" and provided response data
+    # GIVEN a data record with status "INPROGRESS" and provided response data
     data_record = DataRecord(
         "key", status="INPROGRESS", response_data='{"body": "execution finished","statusCode": "200"}'
     )

From 82d93fc2255dc01804a53f3493d4c96da5ebc72a Mon Sep 17 00:00:00 2001
From: Heitor Lessa <heitor.lessa@hotmail.com>
Date: Mon, 31 Jan 2022 14:21:25 +0100
Subject: [PATCH 10/12] chore: correct name for mypy step

---
 .github/workflows/python_build.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/python_build.yml b/.github/workflows/python_build.yml
index 98a574bd94d..7af7bb8e4ba 100644
--- a/.github/workflows/python_build.yml
+++ b/.github/workflows/python_build.yml
@@ -30,7 +30,7 @@ jobs:
         run: make dev
       - name: Formatting and Linting
         run: make lint
-      - name: Typing
+      - name: Static type checking
         run: make mypy
       - name: Test with pytest
         run: make test

From cd8fa872075012e5433be1bfaf9da508bffd66bb Mon Sep 17 00:00:00 2001
From: heitorlessa <lessa@amazon.co.uk>
Date: Mon, 31 Jan 2022 14:28:23 +0100
Subject: [PATCH 11/12] chore(ci): ensure mypy runs on publish and locally

---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 5b8e9b0d689..fc350ac6923 100644
--- a/Makefile
+++ b/Makefile
@@ -29,7 +29,7 @@ coverage-html:
 pre-commit:
 	pre-commit run --show-diff-on-failure
 
-pr: lint pre-commit test security-baseline complexity-baseline
+pr: lint mypy pre-commit test security-baseline complexity-baseline
 
 build: pr
 	poetry build

From c72d51083d329d3f27da51869ae8877b62d41e50 Mon Sep 17 00:00:00 2001
From: heitorlessa <lessa@amazon.co.uk>
Date: Mon, 31 Jan 2022 14:39:53 +0100
Subject: [PATCH 12/12] docs(contributing): add mypy and other fixes

---
 CONTRIBUTING.md | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 0941fbc535b..060726ec11a 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -49,13 +49,14 @@ You might find useful to run both the documentation website and the API referenc
 
 Category | Convention
 ------------------------------------------------- | ---------------------------------------------------------------------------------
-**Docstring** |  We use a slight variation of numpy convention with markdown to help generate more readable API references.
-**Style guide** | We use black as well as flake8 extensions to enforce beyond good practices [PEP8](https://pep8.org/). We strive to make use of type annotation as much as possible, but don't overdo in creating custom types.
+**Docstring** |  We use a slight variation of Numpy convention with markdown to help generate more readable API references.
+**Style guide** | We use black as well as flake8 extensions to enforce beyond good practices [PEP8](https://pep8.org/). We use type annotations and enforce static type checking at CI (mypy).
 **Core utilities** | Core utilities use a Class, always accept `service` as a constructor parameter, can work in isolation, and are also available in other languages implementation.
 **Utilities** | Utilities are not as strict as core and focus on solving a developer experience problem while following the project [Tenets](https://awslabs.github.io/aws-lambda-powertools-python/#tenets).
 **Exceptions** | Specific exceptions live within utilities themselves and use `Error` suffix e.g. `MetricUnitError`.
-**Git commits** | We follow [conventional commits](https://www.conventionalcommits.org/en/v1.0.0/). These are not enforced as we squash and merge PRs, but PR titles are enforced during CI.
-**Documentation** | API reference docs are generated from docstrings which should have Examples section to allow developers to have what they need within their own IDE. Documentation website covers the wider usage, tips, and strive to be concise.
+**Git commits** | We follow [conventional commits](https://www.conventionalcommits.org/en/v1.0.0/). We do not enforce conventional commits on contributors to lower the entry bar. Instead, we enforce a conventional PR title so our label automation and changelog are generated correctly.
+**API documentation** | API reference docs are generated from docstrings which should have Examples section to allow developers to have what they need within their own IDE. Documentation website covers the wider usage, tips, and strive to be concise.
+**Documentation** | We treat it like a product. We sub-divide content aimed at getting started (80% of customers) vs advanced usage (20%). We also ensure customers know how to unit test their code when using our features.
 
 ## Finding contributions to work on