Add GAX client_config to Datastore service factory

Replace retries value with the GAX client configuration.
This leaks the GAX implementation to the public API.
If Gax changes its implementation this may result in a change to
the google-cloud-datastore public API.

google-cloud-datastore/acceptance/datastore_helper.rb

@@ -19,7 +19,7 @@
 require "google/cloud/datastore"
 
 # Create shared dataset object so we don't create new for each test
-$dataset = Google::Cloud.new.datastore retries: 10
+$dataset = Google::Cloud.new.datastore
 
 module Acceptance
   ##

google-cloud-datastore/lib/google-cloud-datastore.rb

@@ -38,8 +38,9 @@ module Cloud
     #   The default scope is:
     #
     #   * `https://www.googleapis.com/auth/datastore`
-    # @param [Integer] retries This option is not currently supported.
     # @param [Integer] timeout Default timeout to use in requests. Optional.
+    # @param [Hash] client_config A hash of values to override the default
+    #   behavior of the API client. See Google::Gax::CallSettings. Optional.
     #
     # @return [Google::Cloud::Datastore::Dataset]
     #
@@ -65,10 +66,10 @@ module Cloud
     #   platform_scope = "https://www.googleapis.com/auth/cloud-platform"
     #   datastore = gcloud.datastore scope: platform_scope
     #
-    def datastore scope: nil, retries: nil, timeout: nil
+    def datastore scope: nil, timeout: nil, client_config: nil
       Google::Cloud.datastore @project, @keyfile,
-                              scope: scope, retries: retries,
-                              timeout: (timeout || @timeout)
+                              scope: scope, timeout: (timeout || @timeout),
+                              client_config: client_config
     end
 
     ##
@@ -90,8 +91,9 @@ def datastore scope: nil, retries: nil, timeout: nil
     #   The default scope is:
     #
     #   * `https://www.googleapis.com/auth/datastore`
-    # @param [Integer] retries This option is not currently supported.
     # @param [Integer] timeout Default timeout to use in requests. Optional.
+    # @param [Hash] client_config A hash of values to override the default
+    #   behavior of the API client. See Google::Gax::CallSettings. Optional.
     #
     # @return [Google::Cloud::Datastore::Dataset]
     #
@@ -106,16 +108,16 @@ def datastore scope: nil, retries: nil, timeout: nil
     #     t["done"] = false
     #     t["priority"] = 4
     #     t["description"] = "Learn Cloud Datastore"
-    #   end
+    #   end                                                                  ``
     #
     #   datastore.save task
     #
-    def self.datastore project = nil, keyfile = nil, scope: nil, retries: nil,
-                       timeout: nil
+    def self.datastore project = nil, keyfile = nil, scope: nil, timeout: nil,
+                       client_config: nil
       require "google/cloud/datastore"
       Google::Cloud::Datastore.new project: project, keyfile: keyfile,
-                                   scope: scope, retries: retries,
-                                   timeout: timeout
+                                   scope: scope, timeout: timeout,
+                                   client_config: client_config
     end
   end
 end

google-cloud-datastore/lib/google/cloud/datastore.rb

@@ -518,9 +518,9 @@ module Datastore
       #   The default scope is:
       #
       #   * `https://www.googleapis.com/auth/datastore`
-      # @param [Integer] retries Number of times to retry requests on server
-      #   error. The default value is `3`. Optional.
       # @param [Integer] timeout Default timeout to use in requests. Optional.
+      # @param [Hash] client_config A hash of values to override the default
+      #   behavior of the API client. See Google::Gax::CallSettings. Optional.
       #
       # @return [Google::Cloud::Datastore::Dataset]
       #
@@ -541,8 +541,8 @@ module Datastore
       #
       #   datastore.save task
       #
-      def self.new project: nil, keyfile: nil, scope: nil, retries: nil,
-                   timeout: nil
+      def self.new project: nil, keyfile: nil, scope: nil, timeout: nil,
+                   client_config: nil
         project ||= Google::Cloud::Datastore::Dataset.default_project
         project = project.to_s # Always cast to a string
         fail ArgumentError, "project is missing" if project.empty?
@@ -551,20 +551,24 @@ def self.new project: nil, keyfile: nil, scope: nil, retries: nil,
           return Google::Cloud::Datastore::Dataset.new(
             Google::Cloud::Datastore::Service.new(
               project, :this_channel_is_insecure,
-              host: ENV["DATASTORE_EMULATOR_HOST"], retries: retries))
+              host: ENV["DATASTORE_EMULATOR_HOST"],
+              client_config: client_config))
         end
+        credentials = credentials_with_scope keyfile, scope
+        Google::Cloud::Datastore::Dataset.new(
+          Google::Cloud::Datastore::Service.new(
+            project, credentials, timeout: timeout,
+                                  client_config: client_config))
+      end
 
+      ##
+      # @private
+      def self.credentials_with_scope keyfile, scope
         if keyfile.nil?
-          credentials = Google::Cloud::Datastore::Credentials.default(
-            scope: scope)
+          Google::Cloud::Datastore::Credentials.default(scope: scope)
         else
-          credentials = Google::Cloud::Datastore::Credentials.new(
-            keyfile, scope: scope)
+          Google::Cloud::Datastore::Credentials.new(keyfile, scope: scope)
         end
-
-        Google::Cloud::Datastore::Dataset.new(
-          Google::Cloud::Datastore::Service.new(
-            project, credentials, retries: retries, timeout: timeout))
       end
     end
   end

google-cloud-datastore/lib/google/cloud/datastore/service.rb

@@ -16,8 +16,8 @@
 require "google/cloud/errors"
 require "google/cloud/datastore/credentials"
 require "google/cloud/datastore/version"
-require "google/datastore/v1/datastore_services_pb"
-require "google/cloud/datastore/v1/datastore_api"
+require "google/cloud/datastore/v1"
+require "google/gax/errors"
 
 module Google
   module Cloud
@@ -26,38 +26,40 @@ module Datastore
       # @private Represents the GAX Datastore service, including all the API
       # methods.
       class Service
-        attr_accessor :project, :credentials, :host, :retries, :timeout
+        attr_accessor :project, :credentials, :host, :timeout, :client_config
 
         ##
         # Creates a new Service instance.
-        def initialize project, credentials, host: nil, retries: nil,
-                       timeout: nil
+        def initialize project, credentials, host: nil, timeout: nil,
+                       client_config: nil
           @project = project
           @credentials = credentials
           @host = host || V1::DatastoreApi::SERVICE_ADDRESS
-          @retries = retries
           @timeout = timeout
+          @client_config = client_config || {}
         end
 
         def channel
+          require "grpc"
           GRPC::Core::Channel.new host, nil, chan_creds
         end
 
         def chan_creds
           return credentials if insecure?
+          require "grpc"
           GRPC::Core::ChannelCredentials.new.compose \
             GRPC::Core::CallCredentials.new credentials.client.updater_proc
         end
 
         def service
           return mocked_service if mocked_service
-          @service ||= \
-            V1::DatastoreApi.new(
-              service_path: host,
-              channel: channel,
-              timeout: timeout,
-              app_name: "google-cloud-datastore",
-              app_version: Google::Cloud::Datastore::VERSION)
+          @service ||= V1::DatastoreApi.new(
+            service_path: host,
+            channel: channel,
+            timeout: timeout,
+            client_config: client_config,
+            app_name: "google-cloud-datastore",
+            app_version: Google::Cloud::Datastore::VERSION)
         end
         attr_accessor :mocked_service
 
@@ -143,10 +145,10 @@ def generate_read_options consistency, transaction
         end
 
         def execute
-          require "grpc" # Ensure GRPC is loaded before rescuing exception
           yield
-        rescue GRPC::BadStatus => e
-          raise Google::Cloud::Error.from_error(e)
+        rescue Google::Gax::GaxError => e
+          # GaxError wraps BadStatus, but exposes it as #cause
+          raise Google::Cloud::Error.from_error(e.cause)
         end
       end
     end

google-cloud-datastore/lib/google/cloud/datastore/v1.rb

@@ -14,3 +14,5 @@
 
 
 require "google/cloud/datastore/v1/datastore_api"
+# Require the protobufs so we can create objects before GRPC is loaded.
+require "google/datastore/v1/datastore_pb"

google-cloud-datastore/test/google/cloud/datastore_test.rb

@@ -19,12 +19,12 @@
   describe "#datastore" do
     it "calls out to Google::Cloud.datastore" do
       gcloud = Google::Cloud.new
-      stubbed_datastore = ->(project, keyfile, scope: nil, retries: nil, timeout: nil) {
+      stubbed_datastore = ->(project, keyfile, scope: nil, timeout: nil, client_config: nil) {
         project.must_equal nil
         keyfile.must_equal nil
         scope.must_be :nil?
-        retries.must_be :nil?
         timeout.must_be :nil?
+        client_config.must_be :nil?
         "datastore-dataset-object-empty"
       }
       Google::Cloud.stub :datastore, stubbed_datastore do
@@ -35,12 +35,12 @@
 
     it "passes project and keyfile to Google::Cloud.datastore" do
       gcloud = Google::Cloud.new "project-id", "keyfile-path"
-      stubbed_datastore = ->(project, keyfile, scope: nil, retries: nil, timeout: nil) {
+      stubbed_datastore = ->(project, keyfile, scope: nil, timeout: nil, client_config: nil) {
         project.must_equal "project-id"
         keyfile.must_equal "keyfile-path"
         scope.must_be :nil?
-        retries.must_be :nil?
         timeout.must_be :nil?
+        client_config.must_be :nil?
         "datastore-dataset-object"
       }
       Google::Cloud.stub :datastore, stubbed_datastore do
@@ -51,16 +51,16 @@
 
     it "passes project and keyfile and options to Google::Cloud.datastore" do
       gcloud = Google::Cloud.new "project-id", "keyfile-path"
-      stubbed_datastore = ->(project, keyfile, scope: nil, retries: nil, timeout: nil) {
+      stubbed_datastore = ->(project, keyfile, scope: nil, timeout: nil, client_config: nil) {
         project.must_equal "project-id"
         keyfile.must_equal "keyfile-path"
         scope.must_equal "http://example.com/scope"
-        retries.must_equal 5
         timeout.must_equal 60
+        client_config.must_equal({ "gax" => "options" })
         "datastore-dataset-object-scoped"
       }
       Google::Cloud.stub :datastore, stubbed_datastore do
-        dataset = gcloud.datastore scope: "http://example.com/scope", retries: 5, timeout: 60
+        dataset = gcloud.datastore scope: "http://example.com/scope", timeout: 60, client_config: { "gax" => "options" }
         dataset.must_equal "datastore-dataset-object-scoped"
       end
     end
@@ -91,11 +91,11 @@
         scope.must_equal nil
         "datastore-credentials"
       }
-      stubbed_service = ->(project, credentials, retries: nil, timeout: nil) {
+      stubbed_service = ->(project, credentials, timeout: nil, client_config: nil) {
         project.must_equal "project-id"
         credentials.must_equal "datastore-credentials"
-        retries.must_equal nil
         timeout.must_equal nil
+        client_config.must_equal nil
         OpenStruct.new project: project
       }
 
@@ -142,11 +142,11 @@
         scope.must_equal nil
         "datastore-credentials"
       }
-      stubbed_service = ->(project, credentials, retries: nil, timeout: nil) {
+      stubbed_service = ->(project, credentials, timeout: nil, client_config: nil) {
         project.must_equal "project-id"
         credentials.must_equal "datastore-credentials"
-        retries.must_equal nil
         timeout.must_equal nil
+        client_config.must_equal nil
         OpenStruct.new project: project
       }