docs(samples): add sample to update secret with alias (#307)

Update code samples for Access By alias Launch

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Fixes #<issue_number_goes_here> 🦕

secretmanager/snippets/snippets_test.py

@@ -41,6 +41,7 @@
 from list_secrets_with_filter import list_secrets_with_filter
 from quickstart import quickstart
 from update_secret import update_secret
+from update_secret_with_alias import update_secret_with_alias
 from update_secret_with_etag import update_secret_with_etag
 
 
@@ -290,3 +291,9 @@ def test_update_secret_with_etag(secret):
     project_id, secret_id, etag = secret
     secret = update_secret_with_etag(project_id, secret_id, etag)
     assert secret.labels["secretmanager"] == "rocks"
+
+
+def test_update_secret_with_alias(secret_version):
+    project_id, secret_id, version_id, _ = secret_version
+    secret = update_secret_with_alias(project_id, secret_id)
+    assert secret.version_aliases["test"] == 1

secretmanager/snippets/update_secret_with_alias.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+
+# Copyright 2022 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+
+import argparse
+
+
+# [START secretmanager_update_secret_with_alias]
+def update_secret_with_alias(project_id, secret_id):
+    """
+    Update the metadata about an existing secret.
+    """
+
+    # Import the Secret Manager client library.
+    from google.cloud import secretmanager
+
+    # Create the Secret Manager client.
+    client = secretmanager.SecretManagerServiceClient()
+
+    # Build the resource name of the secret.
+    name = client.secret_path(project_id, secret_id)
+
+    # Update the secret.
+    secret = {"name": name, "version_aliases": {"test": 1}}
+    update_mask = {"paths": ["version_aliases"]}
+    response = client.update_secret(
+        request={"secret": secret, "update_mask": update_mask}
+    )
+
+    # Print the new secret name.
+    print("Updated secret: {}".format(response.name))
+    # [END secretmanager_update_secret_with_alias]
+
+    return response
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter
+    )
+    parser.add_argument("project_id", help="id of the GCP project")
+    parser.add_argument("--secret-id", required=True)
+    args = parser.parse_args()
+
+    update_secret_with_alias(args.project_id, args.secret_id)