chore: Add support policy (#170)

Author: farleyb-amazon

README.rst

@@ -38,6 +38,8 @@ You can find our source on `GitHub`_.
 
 `Security issue notifications`_
 
+See `Support Policy`_ for details on the current support status of all major versions of this library.
+
 ***************
 Getting Started
 ***************
@@ -193,3 +195,4 @@ of the one that the client would normally construct for you.
 .. _decrypt_dynamodb_item: https://aws-dynamodb-encryption-python.readthedocs.io/en/latest/lib/encrypted/item.html#dynamodb_encryption_sdk.encrypted.item.decrypt_dynamodb_item
 .. _transformation functions: https://aws-dynamodb-encryption-python.readthedocs.io/en/latest/lib/tools/transform.html
 .. _Security issue notifications: https://github.com/aws/aws-dynamodb-encryption-python/blob/master/CONTRIBUTING.md#user-content-security-issue-notifications
+.. _Support Policy: https://github.com/aws/aws-dynamodb-encryption-python/blob/master/SUPPORT_POLICY.rst

SUPPORT_POLICY.rst

@@ -0,0 +1,33 @@
+Overview
+========
+This page describes the support policy for the AWS DynamoDB Encryption Client. We regularly provide the AWS DynamoDB Encryption Client with updates that may contain support for new or updated APIs, new features, enhancements, bug fixes, security patches, or documentation updates. Updates may also address changes with dependencies, language runtimes, and operating systems.
+
+We recommend users to stay up-to-date with DynamoDB Encryption Client releases to keep up with the latest features, security updates, and underlying dependencies. Continued use of an unsupported SDK version is not recommended and is done at the user’s discretion.
+
+
+Major Version Lifecycle
+========================
+The AWS DynamoDB Encryption Client follows the same major version lifecycle as the AWS SDK. For details on this lifecycle, see  `AWS SDKs and Tools Maintenance Policy`_.
+
+Version Support Matrix
+======================
+This table describes the current support status of each major version of the AWS DynamoDB Encryption Client for Python. It also shows the next status each major version will transition to, and the date at which that transition will happen.
+
+.. list-table::
+    :widths: 30 50 50 50
+    :header-rows: 1
+
+    * - Major version
+      - Current status
+      - Next status
+      - Next status date
+    * - 1.x
+      - Maintenance
+      - End of Support
+      - 2022-07-08
+    * - 2.x
+      - Generally Available
+      -
+      -
+
+.. _AWS SDKs and Tools Maintenance Policy: https://docs.aws.amazon.com/sdkref/latest/guide/maint-policy.html#version-life-cycle

doc/conf.py

@@ -11,7 +11,7 @@
 
 def read(*args):
     """Reads complete file contents."""
-    return io.open(os.path.join(HERE, *args), encoding="utf-8").read()
+    return io.open(os.path.join(HERE, *args), encoding="utf-8").read()  # pylint: disable=consider-using-with
 
 
 def get_release():

setup.py

@@ -11,7 +11,7 @@
 
 def read(*args):
     """Reads complete file contents."""
-    return io.open(os.path.join(HERE, *args), encoding="utf-8").read()
+    return io.open(os.path.join(HERE, *args), encoding="utf-8").read()  # pylint: disable=consider-using-with
 
 
 def get_version():

src/dynamodb_encryption_sdk/delegated_keys/__init__.py

@@ -45,7 +45,8 @@ class DelegatedKey(object):
     a :class:`NotImplementedError` detailing this.
     """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def algorithm(self):
         # type: () -> Text
         """Text description of algorithm used by this delegated key."""

src/dynamodb_encryption_sdk/materials/__init__.py

@@ -33,7 +33,8 @@
 class CryptographicMaterials(object):
     """Base class for all cryptographic materials."""
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def material_description(self):
         # type: () -> Dict[Text, Text]
         """Material description to use with these cryptographic materials.
@@ -42,7 +43,8 @@ def material_description(self):
         :rtype: dict
         """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def encryption_key(self):
         # type: () -> DelegatedKey
         """Delegated key used for encrypting attributes.
@@ -51,7 +53,8 @@ def encryption_key(self):
         :rtype: DelegatedKey
         """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def decryption_key(self):
         # type: () -> DelegatedKey
         """Delegated key used for decrypting attributes.
@@ -60,7 +63,8 @@ def decryption_key(self):
         :rtype: DelegatedKey
         """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def signing_key(self):
         # type: () -> DelegatedKey
         """Delegated key used for calculating digital signatures.
@@ -69,7 +73,8 @@ def signing_key(self):
         :rtype: DelegatedKey
         """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def verification_key(self):
         # type: () -> DelegatedKey
         """Delegated key used for verifying digital signatures.