feat: add client_encryped_cert_source to ClientOptions (googleapis#31)

Author: arithmetic1728

google/api_core/client_options.py

@@ -56,12 +56,31 @@ class ClientOptions(object):
         api_endpoint (str): The desired API endpoint, e.g., compute.googleapis.com
         client_cert_source (Callable[[], (bytes, bytes)]): An optional callback
             which returns client certificate bytes and private key bytes both in
-            PEM format.
+            PEM format. ``client_cert_source`` and ``client_encrypted_cert_source``
+            are mutually exclusive.
+        client_encrypted_cert_source (Callable[[], (str, str, bytes)]): An optional
+            callback which returns client certificate file path, encrypted private
+            key file path, and the passphrase bytes.``client_cert_source`` and
+            ``client_encrypted_cert_source`` are mutually exclusive.
+
+    Raises:
+        ValueError: If both ``client_cert_source`` and ``client_encrypted_cert_source``
+            are provided.
     """
 
-    def __init__(self, api_endpoint=None, client_cert_source=None):
+    def __init__(
+        self,
+        api_endpoint=None,
+        client_cert_source=None,
+        client_encrypted_cert_source=None,
+    ):
+        if client_cert_source and client_encrypted_cert_source:
+            raise ValueError(
+                "client_cert_source and client_encrypted_cert_source are mutually exclusive"
+            )
         self.api_endpoint = api_endpoint
         self.client_cert_source = client_cert_source
+        self.client_encrypted_cert_source = client_encrypted_cert_source
 
     def __repr__(self):
         return "ClientOptions: " + repr(self.__dict__)

tests/unit/test_client_options.py

@@ -21,6 +21,10 @@ def get_client_cert():
     return b"cert", b"key"
 
 
+def get_client_encrypted_cert():
+    return "cert_path", "key_path", b"passphrase"
+
+
 def test_constructor():
 
     options = client_options.ClientOptions(
@@ -31,6 +35,30 @@ def test_constructor():
     assert options.client_cert_source() == (b"cert", b"key")
 
 
+def test_constructor_with_encrypted_cert_source():
+
+    options = client_options.ClientOptions(
+        api_endpoint="foo.googleapis.com",
+        client_encrypted_cert_source=get_client_encrypted_cert,
+    )
+
+    assert options.api_endpoint == "foo.googleapis.com"
+    assert options.client_encrypted_cert_source() == (
+        "cert_path",
+        "key_path",
+        b"passphrase",
+    )
+
+
+def test_constructor_with_both_cert_sources():
+    with pytest.raises(ValueError):
+        client_options.ClientOptions(
+            api_endpoint="foo.googleapis.com",
+            client_cert_source=get_client_cert,
+            client_encrypted_cert_source=get_client_encrypted_cert,
+        )
+
+
 def test_from_dict():
     options = client_options.from_dict(
         {"api_endpoint": "foo.googleapis.com", "client_cert_source": get_client_cert}
@@ -57,6 +85,6 @@ def test_repr():
 
     assert (
         repr(options)
-        == "ClientOptions: {'api_endpoint': 'foo.googleapis.com', 'client_cert_source': None}"
-        or "ClientOptions: {'client_cert_source': None, 'api_endpoint': 'foo.googleapis.com'}"
+        == "ClientOptions: {'api_endpoint': 'foo.googleapis.com', 'client_cert_source': None, 'client_encrypted_cert_source': None}"
+        or "ClientOptions: {'client_encrypted_cert_source': None, 'client_cert_source': None, 'api_endpoint': 'foo.googleapis.com'}"
     )