Merge pull request #103 from AzureAD/unified-persistence-api

Making all platform-dependent parameters optional

Author: rayluo

msal_extensions/persistence.py

@@ -9,6 +9,7 @@
 import abc
 import os
 import errno
+import hashlib
 import logging
 import sys
 try:
@@ -50,6 +51,9 @@ def _mkdir_p(path):
         else:
             raise
 
+def _auto_hash(input_string):
+    return hashlib.sha256(input_string.encode('utf-8')).hexdigest()
+
 
 # We do not aim to wrap every os-specific exception.
 # Here we define only the most common one,
@@ -197,19 +201,18 @@ class KeychainPersistence(BasePersistence):
     and protected by native Keychain libraries on OSX"""
     is_encrypted = True
 
-    def __init__(self, signal_location, service_name, account_name):
+    def __init__(self, signal_location, service_name=None, account_name=None):
         """Initialization could fail due to unsatisfied dependency.
 
         :param signal_location: See :func:`persistence.LibsecretPersistence.__init__`
         """
-        if not (service_name and account_name):  # It would hang on OSX
-            raise ValueError("service_name and account_name are required")
         from .osx import Keychain, KeychainError  # pylint: disable=import-outside-toplevel
         self._file_persistence = FilePersistence(signal_location)  # Favor composition
         self._Keychain = Keychain  # pylint: disable=invalid-name
         self._KeychainError = KeychainError  # pylint: disable=invalid-name
-        self._service_name = service_name
-        self._account_name = account_name
+        default_service_name = "msal-extensions"  # This is also our package name
+        self._service_name = service_name or default_service_name
+        self._account_name = account_name or _auto_hash(signal_location)
 
     def save(self, content):
         with self._Keychain() as locker:
@@ -247,7 +250,7 @@ class LibsecretPersistence(BasePersistence):
     and protected by native libsecret libraries on Linux"""
     is_encrypted = True
 
-    def __init__(self, signal_location, schema_name, attributes, **kwargs):
+    def __init__(self, signal_location, schema_name=None, attributes=None, **kwargs):
         """Initialization could fail due to unsatisfied dependency.
 
         :param string signal_location:
@@ -262,7 +265,8 @@ def __init__(self, signal_location, schema_name, attributes, **kwargs):
         from .libsecret import (  # This uncertain import is deferred till runtime
             LibSecretAgent, trial_run)
         trial_run()
-        self._agent = LibSecretAgent(schema_name, attributes, **kwargs)
+        self._agent = LibSecretAgent(
+            schema_name or _auto_hash(signal_location), attributes or {}, **kwargs)
         self._file_persistence = FilePersistence(signal_location)  # Favor composition
 
     def save(self, content):

sample/persistence_sample.py

@@ -10,7 +10,7 @@ def build_persistence(location, fallback_to_plaintext=False):
     if sys.platform.startswith('win'):
         return FilePersistenceWithDataProtection(location)
     if sys.platform.startswith('darwin'):
-        return KeychainPersistence(location, "my_service_name", "my_account_name")
+        return KeychainPersistence(location)
     if sys.platform.startswith('linux'):
         try:
             return LibsecretPersistence(
@@ -21,8 +21,6 @@ def build_persistence(location, fallback_to_plaintext=False):
                 # unless there would frequently be a desktop session and
                 # a remote ssh session being active simultaneously.
                 location,
-                schema_name="my_schema_name",
-                attributes={"my_attr1": "foo", "my_attr2": "bar"},
                 )
         except:  # pylint: disable=bare-except
             if not fallback_to_plaintext:
@@ -31,6 +29,7 @@ def build_persistence(location, fallback_to_plaintext=False):
     return FilePersistence(location)
 
 persistence = build_persistence("storage.bin", fallback_to_plaintext=False)
+print("Type of persistence: {}".format(persistence.__class__.__name__))
 print("Is this persistence encrypted?", persistence.is_encrypted)
 
 data = {  # It can be anything, here we demonstrate an arbitrary json object

sample/token_cache_sample.py

@@ -10,7 +10,7 @@ def build_persistence(location, fallback_to_plaintext=False):
     if sys.platform.startswith('win'):
         return FilePersistenceWithDataProtection(location)
     if sys.platform.startswith('darwin'):
-        return KeychainPersistence(location, "my_service_name", "my_account_name")
+        return KeychainPersistence(location)
     if sys.platform.startswith('linux'):
         try:
             return LibsecretPersistence(
@@ -21,8 +21,6 @@ def build_persistence(location, fallback_to_plaintext=False):
                 # unless there would frequently be a desktop session and
                 # a remote ssh session being active simultaneously.
                 location,
-                schema_name="my_schema_name",
-                attributes={"my_attr1": "foo", "my_attr2": "bar"},
                 )
         except:  # pylint: disable=bare-except
             if not fallback_to_plaintext:
@@ -31,6 +29,7 @@ def build_persistence(location, fallback_to_plaintext=False):
     return FilePersistence(location)
 
 persistence = build_persistence("token_cache.bin")
+print("Type of persistence: {}".format(persistence.__class__.__name__))
 print("Is this persistence encrypted?", persistence.is_encrypted)
 
 cache = PersistedTokenCache(persistence)

tests/test_persistence.py

@@ -54,8 +54,7 @@ def test_nonexistent_file_persistence_with_data_protection(temp_location):
     not sys.platform.startswith('darwin'),
     reason="Requires OSX. Whether running on TRAVIS CI does not seem to matter.")
 def test_keychain_persistence(temp_location):
-    _test_persistence_roundtrip(KeychainPersistence(
-        temp_location, "my_service_name", "my_account_name"))
+    _test_persistence_roundtrip(KeychainPersistence(temp_location))
 
 @pytest.mark.skipif(
     not sys.platform.startswith('darwin'),
@@ -69,11 +68,7 @@ def test_nonexistent_keychain_persistence(temp_location):
     is_running_on_travis_ci or not sys.platform.startswith('linux'),
     reason="Requires Linux Desktop. Headless or SSH session won't work.")
 def test_libsecret_persistence(temp_location):
-    _test_persistence_roundtrip(LibsecretPersistence(
-        temp_location,
-        "my_schema_name",
-        {"my_attr_1": "foo", "my_attr_2": "bar"},
-        ))
+    _test_persistence_roundtrip(LibsecretPersistence(temp_location))
 
 @pytest.mark.skipif(
     is_running_on_travis_ci or not sys.platform.startswith('linux'),