Make recipients optional when encrypting files.

If no recipients are defined, use all loaded keys.

Change-Id: I0e465f83ee2537d1aabf8608da1fc5b143374ce9

edx/analytics/tasks/encrypt.py

@@ -17,8 +17,15 @@ log = logging.getLogger(__name__)
 
 
 @contextmanager
-def make_encrypted_file(output_file, key_file_targets, recipients):
-    """Creates a file object to be written to, whose contents will afterwards be encrypted."""
+def make_encrypted_file(output_file, key_file_targets, recipients=None):
+    """
+    Creates a file object to be written to, whose contents will afterwards be encrypted.
+
+    Parameters:
+        output_file:  a file object, opened for writing.
+        key_file_targets: a list of luigi.Target objects defining the gpg public key files to be loaded.
+        recipients:  an optional list of recipients to be loaded.  If not specified, uses all loaded keys.
+    """
     with make_temp_directory(prefix="encrypt") as temp_dir:
         # Use temp directory to hold gpg keys.
         gpg = gnupg.GPG(gnupghome=temp_dir)
@@ -31,6 +38,8 @@ def make_encrypted_file(output_file, key_file_targets, recipients):
 
         # Encryption produces a second file in the same temp directory.
         temp_encrypted_filepath = "{filepath}.gpg".format(filepath=temp_input_filepath)
+        if recipients is None:
+            recipients = [key['keyid'] for key in gpg.list_keys()]
         with open(temp_input_filepath, 'r') as temp_input_file:
             _encrypt_file(gpg, temp_input_file, temp_encrypted_filepath, recipients)
         _copy_file_to_open_file(temp_encrypted_filepath, output_file)
@@ -109,7 +118,7 @@ class FakeEventExportWithEncryptionTask(MultiOutputMapReduceJobTask):
         org_id, _server_id = key
         recipients = self._get_recipients(org_id)
         key_file_targets = [get_target_from_url(url_path_join(self.gpg_key_dir, recipient)) for recipient in recipients]
-        with make_encrypted_file(output_file, key_file_targets, recipients) as encrypted_output_file:
+        with make_encrypted_file(output_file, key_file_targets) as encrypted_output_file:
             for value in values:
                 encrypted_output_file.write(value)
                 encrypted_output_file.write('\n')

edx/analytics/tasks/tests/test_encrypt.py

@@ -13,6 +13,12 @@ from edx.analytics.tasks.util.tempdir import make_temp_directory
 class MakeEncryptedFileTest(unittest.TestCase):
     """Test make_encrypted_file context manager."""
 
+    def setUp(self):
+        self.recipient = 'daemon@edx.org'
+        self.gpg_key_dir = 'gpg-keys'
+        self.recipient_private_key = 'insecure_secret.key'
+        self.key_file_targets = [get_target_from_url(url_path_join(self.gpg_key_dir, self.recipient))]
+
     def get_decrypted_data(self, input_file, key_file_target):
         """Decrypts contents of input, and writes to output file object open for writing."""
         with make_temp_directory(prefix="decrypt") as temp_dir:
@@ -22,21 +28,30 @@ class MakeEncryptedFileTest(unittest.TestCase):
             decrypted_data = gpg_instance.decrypt_file(input_file, always_trust=True)
             return decrypted_data
 
+    def check_encrypted_data(self, encrypted_file, expected_values):
+        """Decrypt the file and compare against expected values."""
+        key_file_target = get_target_from_url(url_path_join(self.gpg_key_dir, self.recipient_private_key))
+        decrypted_data = self.get_decrypted_data(encrypted_file, key_file_target)
+        self.assertEquals(str(decrypted_data).strip().split('\n'), expected_values)
+
     def test_make_encrypted_file(self):
-        recipient = 'daemon@edx.org'
-        gpg_key_dir = 'gpg-keys'
-        key_file_targets = [get_target_from_url(url_path_join(gpg_key_dir, recipient))]
         values = ['this', 'is', 'a', 'test']
         with tempfile.NamedTemporaryFile() as output_file:
-            with make_encrypted_file(output_file, key_file_targets, [recipient]) as encrypted_output_file:
+            with make_encrypted_file(output_file, self.key_file_targets, [self.recipient]) as encrypted_output_file:
                 for value in values:
                     encrypted_output_file.write(value)
                     encrypted_output_file.write('\n')
 
             output_file.seek(0)
+            self.check_encrypted_data(output_file, values)
 
-            # Decrypt the file and compare.
-            recipient_private_key = 'insecure_secret.key'
-            key_file_target = get_target_from_url(url_path_join(gpg_key_dir, recipient_private_key))
-            decrypted_data = self.get_decrypted_data(output_file, key_file_target)
-            self.assertEquals(values, str(decrypted_data).strip().split('\n'))
+    def test_make_encrypted_file_with_implied_recipients(self):
+        values = ['this', 'is', 'a', 'test']
+        with tempfile.NamedTemporaryFile() as output_file:
+            with make_encrypted_file(output_file, self.key_file_targets) as encrypted_output_file:
+                for value in values:
+                    encrypted_output_file.write(value)
+                    encrypted_output_file.write('\n')
+
+            output_file.seek(0)
+            self.check_encrypted_data(output_file, values)