datastore.rb in google-cloud-datastore-1.3.0

- old
+ new

@@ -1,12 +1,12 @@
-# Copyright 2014 Google Inc. All rights reserved.
+# Copyright 2014 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
+#     https://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
@@ -367,10 +367,34 @@
     # rescue
     #   tx.rollback
     # end
     # ```
     #
+    # A read-only transaction cannot modify entities; in return they do not
+    # contend with other read-write or read-only transactions. Using a read-only
+    # transaction for transactions that only read data will potentially improve
+    # throughput.
+    #
+    # ```ruby
+    # require "google/cloud/datastore"
+    #
+    # datastore = Google::Cloud::Datastore.new
+    #
+    # task_list_key = datastore.key "TaskList", "default"
+    # query = datastore.query("Task").
+    #   ancestor(task_list_key)
+    #
+    # tasks = nil
+    #
+    # datastore.transaction read_only: true do |tx|
+    #   task_list = tx.find task_list_key
+    #   if task_list
+    #     tasks = tx.run query
+    #   end
+    # end
+    # ```
+    #
     # See {Google::Cloud::Datastore::Transaction} and
     # {Google::Cloud::Datastore::Dataset#transaction}
     #
     # ## Querying metadata
     #
@@ -535,12 +559,10 @@
     #
     # datastore.save task
     # ```
     #
     module Datastore
-      # rubocop:disable MethodLength
-
       ##
       # Creates a new object for connecting to the Datastore service.
       # Each call creates a new connection.
       #
       # For more information on connecting to Google Cloud see the
@@ -612,10 +634,8 @@
         Datastore::Dataset.new(
           Datastore::Service.new(
             project_id, credentials,
             timeout: timeout, client_config: client_config))
       end
-
-      # rubocop:enable MethodLength
     end
   end
 end