From c1c805cf6e9c00f2d6796627d919338be1a0599a Mon Sep 17 00:00:00 2001
From: Rajat Bhatta <93644539+rajatbhatta@users.noreply.github.com>
Date: Thu, 29 Sep 2022 23:04:12 +0530
Subject: [PATCH] feat: support customer managed instance configurations
 (#1742)
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

* feat: implementation changes to add support for
customer managed instance configurations.

* test: add more unit tests to Instance admin client

Unit tests each for create, update and delete
instance config operations have been added.

* feat: add samples for create, update and deleting
user managed instance configs.

* chore: add test instance config to samples pom

* test: add CUD instance config integration tests

* feat: add proto file as reference.

* feat: lint the code changes, add documentation

* feat: minor alignment changes

* feat: fix checkstyle violations.

* feat: change read-only fields setters to protected.

* feat: change setConfigType to protected.

* feat: change some more method access modifiers

* feat: add optional fields, some design changes.

* feat: some documentation changes

* feat: change BASE_CONFIG project name in tests.

* feat: pom.xml changes

* feat: add support for adding readonly replicas
while creating instance config.

* feat: clirr changes

* feat: some refactoring

* feat: some method doc changes.

* feat: incorporate review comments.

* feat: remove samples

* Update pom.xml

* Update SampleIdGenerator.java

* Update SampleRunner.java

* Update SampleTestBase.java

* feat: changes to InstanceConfigTest

* feat: changes to pom.xml

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java doc

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* Update google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

* feat: make setBaseConfig protected.

* feat: add method doc for addReadOnlyReplicas

* feat: incorporate review comments.

* feat: deprecate few constructors

* feat: make some methods private

* feat: move initialization to property declaration.

* feat: make InstanceConfig.Builder setters return
InstanceConfig.Builder

* feat: some doc changes

* feat: add support for ListInstanceConfigOperations

* fix: linting

* feat: few changes

* Update spanner_instance_admin.proto

* Update SpannerRpc.java

* feat: remove unnecessary parameter from
GapicSpannerRpc

* feat: clirr fix

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* feat: revert unintended sample changes

Co-authored-by: Knut Olav Løite <koloite@gmail.com>
Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
---
 .../clirr-ignored-differences.xml             |  40 ++
 .../cloud/spanner/InstanceAdminClient.java    | 154 ++++++
 .../spanner/InstanceAdminClientImpl.java      |  97 ++++
 .../google/cloud/spanner/InstanceConfig.java  | 122 ++++-
 .../cloud/spanner/InstanceConfigInfo.java     | 465 +++++++++++++++++-
 .../com/google/cloud/spanner/Options.java     | 117 ++++-
 .../cloud/spanner/spi/v1/GapicSpannerRpc.java |  98 ++++
 .../cloud/spanner/spi/v1/SpannerRpc.java      |  38 +-
 .../spanner/InstanceAdminClientImplTest.java  | 129 +++++
 .../cloud/spanner/InstanceConfigTest.java     |  70 ++-
 10 files changed, 1280 insertions(+), 50 deletions(-)

diff --git a/google-cloud-spanner/clirr-ignored-differences.xml b/google-cloud-spanner/clirr-ignored-differences.xml
index 4c422429c0..039278a643 100644
--- a/google-cloud-spanner/clirr-ignored-differences.xml
+++ b/google-cloud-spanner/clirr-ignored-differences.xml
@@ -35,6 +35,46 @@
     <className>com/google/cloud/spanner/connection/ConnectionOptions</className>
     <method>com.google.cloud.spanner.Dialect getDialect()</method>
   </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/InstanceAdminClient</className>
+    <method>com.google.api.gax.longrunning.OperationFuture createInstanceConfig(com.google.cloud.spanner.InstanceConfigInfo, com.google.cloud.spanner.Options$CreateAdminApiOption[])</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/InstanceAdminClient</className>
+    <method>com.google.api.gax.longrunning.OperationFuture updateInstanceConfig(com.google.cloud.spanner.InstanceConfigInfo, java.lang.Iterable, com.google.cloud.spanner.Options$UpdateAdminApiOption[])</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/InstanceAdminClient</className>
+    <method>void deleteInstanceConfig(java.lang.String, com.google.cloud.spanner.Options$DeleteAdminApiOption[])</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/InstanceAdminClient</className>
+    <method>com.google.api.gax.paging.Page listInstanceConfigOperations(com.google.cloud.spanner.Options$ListOption[])</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/spi/v1/SpannerRpc</className>
+    <method>com.google.api.gax.longrunning.OperationFuture createInstanceConfig(java.lang.String, java.lang.String, com.google.spanner.admin.instance.v1.InstanceConfig, java.lang.Boolean)</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/spi/v1/SpannerRpc</className>
+    <method>com.google.api.gax.longrunning.OperationFuture updateInstanceConfig(com.google.spanner.admin.instance.v1.InstanceConfig, java.lang.Boolean, com.google.protobuf.FieldMask)</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/spi/v1/SpannerRpc</className>
+    <method>void deleteInstanceConfig(java.lang.String, java.lang.String, java.lang.Boolean)</method>
+  </difference>
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/spanner/spi/v1/SpannerRpc</className>
+    <method>com.google.cloud.spanner.spi.v1.SpannerRpc$Paginated listInstanceConfigOperations(int, java.lang.String, java.lang.String)</method>
+  </difference>
   <difference>
     <differenceType>7013</differenceType>
     <className>com/google/cloud/spanner/BackupInfo$Builder</className>
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java
index a84bf04aac..702b9c4059 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClient.java
@@ -19,14 +19,141 @@
 import com.google.api.gax.longrunning.OperationFuture;
 import com.google.api.gax.paging.Page;
 import com.google.cloud.Policy;
+import com.google.cloud.spanner.Options.CreateAdminApiOption;
+import com.google.cloud.spanner.Options.DeleteAdminApiOption;
 import com.google.cloud.spanner.Options.ListOption;
+import com.google.cloud.spanner.Options.UpdateAdminApiOption;
 import com.google.longrunning.Operation;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.UpdateInstanceMetadata;
 
 /** Client to do admin operations on Cloud Spanner Instance and Instance Configs. */
 public interface InstanceAdminClient {
 
+  /**
+   * Creates an instance config and begins preparing it to be used. The returned {@code Operation}
+   * can be used to track the progress of preparing the new instance config. The instance config
+   * name is assigned by the caller and must start with the string 'custom'. If the named instance
+   * config already exists, a SpannerException is thrown.
+   *
+   * <p>Immediately after the request returns:
+   *
+   * <ul>
+   *   <li>The instance config is readable via the API, with all requested attributes.
+   *   <li>The instance config's {@code reconciling} field is set to true. Its state is {@code
+   *       CREATING}.
+   * </ul>
+   *
+   * While the operation is pending:
+   *
+   * <ul>
+   *   <li>Cancelling the operation renders the instance config immediately unreadable via the API.
+   *   <li>Except for deleting the creating resource, all other attempts to modify the instance
+   *       config are rejected.
+   * </ul>
+   *
+   * Upon completion of the returned operation:
+   *
+   * <ul>
+   *   <li>Instances can be created using the instance configuration.
+   *   <li>The instance config's {@code reconciling} field becomes false.
+   *   <li>Its state becomes {@code READY}.
+   * </ul>
+   *
+   * <!--SNIPPET instance_admin_client_create_instance_config-->
+   *
+   * <pre>{@code
+   * String projectId = "my-project";
+   * String baseInstanceConfig = "my-base-config";
+   * String instanceConfigId = "custom-user-config";
+   *
+   * final InstanceConfig baseConfig = instanceAdminClient.getInstanceConfig(baseInstanceConfig);
+   *
+   * List<ReplicaInfo> readOnlyReplicas = ImmutableList.of(baseConfig.getOptionalReplicas().get(0));
+   *
+   * InstanceConfigInfo instanceConfigInfo =
+   *     InstanceConfigInfo.newBuilder(InstanceConfigId.of(projectId, instanceConfigId), baseConfig)
+   *         .setDisplayName(instanceConfigId)
+   *         .addReadOnlyReplicas(readOnlyReplicas)
+   *         .build();
+   *
+   * final OperationFuture<InstanceConfig, CreateInstanceConfigMetadata> operation =
+   *     instanceAdminClient.createInstanceConfig(instanceConfigInfo);
+   *
+   * InstanceConfig instanceConfig = op.get(5, TimeUnit.MINUTES)
+   * }</pre>
+   *
+   * <!--SNIPPET instance_admin_client_create_instance_config-->
+   */
+  default OperationFuture<InstanceConfig, CreateInstanceConfigMetadata> createInstanceConfig(
+      InstanceConfigInfo instanceConfig, CreateAdminApiOption... options) throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
+  /**
+   * Updates a custom instance config. This can not be used to update a Google managed instance
+   * config. The returned {@code Operation} can be used to track the progress of updating the
+   * instance. If the named instance config does not exist, a SpannerException is thrown. The
+   * request must include at least one field to update.
+   *
+   * <p>Only user managed configurations can be updated.
+   *
+   * <p>Immediately after the request returns:
+   *
+   * <ul>
+   *   <li>The instance config's {@code reconciling} field is set to true.
+   * </ul>
+   *
+   * While the operation is pending:
+   *
+   * <ul>
+   *   <li>Cancelling the operation sets its metadata's cancel_time.
+   *   <li>The operation is guaranteed to succeed at undoing all changes, after which point it
+   *       terminates with a `CANCELLED` status.
+   *   <li>All other attempts to modify the instance config are rejected.
+   *   <li>Reading the instance config via the API continues to give the pre-request values.
+   * </ul>
+   *
+   * Upon completion of the returned operation:
+   *
+   * <ul>
+   *   <li>Creating instances using the instance configuration uses the new values.
+   *   <li>The instance config's new values are readable via the API.
+   *   <li>The instance config's {@code reconciling} field becomes false.
+   * </ul>
+   *
+   * <!--SNIPPET instance_admin_client_update_instance_config-->
+   *
+   * <pre>{@code
+   * String projectId = "my-project";
+   * String instanceConfigId = "custom-user-config";
+   * String displayName = "my-display-name";
+   *
+   * InstanceConfigInfo instanceConfigInfo =
+   *     InstanceConfigInfo.newBuilder(InstanceConfigId.of(projectId, instanceConfigId))
+   *         .setDisplayName(displayName)
+   *         .build();
+   *
+   * // Only update display name.
+   * final OperationFuture<InstanceConfig, UpdateInstanceConfigMetadata> operation =
+   *     instanceAdminClient.updateInstanceConfig(
+   *         instanceConfigInfo, ImmutableList.of(InstanceConfigField.DISPLAY_NAME));
+   *
+   * InstanceConfig instanceConfig = operation.get(5, TimeUnit.MINUTES);
+   * }</pre>
+   *
+   * <!--SNIPPET instance_admin_client_update_instance_config-->
+   */
+  default OperationFuture<InstanceConfig, UpdateInstanceConfigMetadata> updateInstanceConfig(
+      InstanceConfigInfo instanceConfig,
+      Iterable<InstanceConfigInfo.InstanceConfigField> fieldsToUpdate,
+      UpdateAdminApiOption... options)
+      throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
   /** Gets an instance config. */
   /* <!--SNIPPET instance_admin_client_get_instance_config-->
    * <pre>{@code
@@ -37,6 +164,28 @@ public interface InstanceAdminClient {
    */
   InstanceConfig getInstanceConfig(String configId) throws SpannerException;
 
+  /**
+   * Deletes a custom instance config. Deletion is only allowed for custom instance configs and when
+   * no instances are using the configuration. If any instances are using the config, a
+   * SpannerException is thrown.
+   *
+   * <p>Only user managed configurations can be deleted.
+   * <!--SNIPPET instance_admin_client_delete_instance_config-->
+   *
+   * <pre>{@code
+   * String projectId = "my-project";
+   * String instanceConfigId = "custom-user-config";
+   *
+   * instanceAdminClient.deleteInstanceConfig(instanceConfigId);
+   * }</pre>
+   *
+   * <!--SNIPPET instance_admin_client_delete_instance_config-->
+   */
+  default void deleteInstanceConfig(String instanceConfigId, DeleteAdminApiOption... options)
+      throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
   /** Lists the supported instance configs for current project. */
   /* <!--SNIPPET instance_admin_client_list_configs-->
    * <pre>{@code
@@ -47,6 +196,11 @@ public interface InstanceAdminClient {
    */
   Page<InstanceConfig> listInstanceConfigs(ListOption... options) throws SpannerException;
 
+  /** Lists long-running instance config operations. */
+  default Page<Operation> listInstanceConfigOperations(ListOption... options) {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
   /**
    * Creates an instance and begins preparing it to begin serving. The returned {@code Operation}
    * can be used to track the progress of preparing the new instance. The instance name is assigned
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClientImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClientImpl.java
index 142540af66..195de83382 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClientImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceAdminClientImpl.java
@@ -23,14 +23,19 @@
 import com.google.api.pathtemplate.PathTemplate;
 import com.google.cloud.Policy;
 import com.google.cloud.Policy.DefaultMarshaller;
+import com.google.cloud.spanner.Options.CreateAdminApiOption;
+import com.google.cloud.spanner.Options.DeleteAdminApiOption;
 import com.google.cloud.spanner.Options.ListOption;
+import com.google.cloud.spanner.Options.UpdateAdminApiOption;
 import com.google.cloud.spanner.SpannerImpl.PageFetcher;
 import com.google.cloud.spanner.spi.v1.SpannerRpc;
 import com.google.cloud.spanner.spi.v1.SpannerRpc.Paginated;
 import com.google.common.base.Preconditions;
 import com.google.longrunning.Operation;
 import com.google.protobuf.FieldMask;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.UpdateInstanceMetadata;
 
 /** Default implementation of {@link InstanceAdminClient} */
@@ -60,6 +65,64 @@ protected com.google.iam.v1.Policy toPb(Policy policy) {
     this.dbClient = dbClient;
   }
 
+  @Override
+  public OperationFuture<InstanceConfig, CreateInstanceConfigMetadata> createInstanceConfig(
+      InstanceConfigInfo instanceConfig, CreateAdminApiOption... options) throws SpannerException {
+    final Options createAdminApiOptions = Options.fromAdminApiOptions(options);
+    String projectName = PROJECT_NAME_TEMPLATE.instantiate("project", projectId);
+    OperationFuture<
+            com.google.spanner.admin.instance.v1.InstanceConfig, CreateInstanceConfigMetadata>
+        rawOperationFuture =
+            rpc.createInstanceConfig(
+                projectName,
+                instanceConfig.getId().getInstanceConfig(),
+                instanceConfig.toProto(),
+                createAdminApiOptions.validateOnly());
+
+    return new OperationFutureImpl<>(
+        rawOperationFuture.getPollingFuture(),
+        rawOperationFuture.getInitialFuture(),
+        snapshot ->
+            InstanceConfig.fromProto(
+                ProtoOperationTransformers.ResponseTransformer.create(
+                        com.google.spanner.admin.instance.v1.InstanceConfig.class)
+                    .apply(snapshot),
+                InstanceAdminClientImpl.this),
+        ProtoOperationTransformers.MetadataTransformer.create(CreateInstanceConfigMetadata.class),
+        e -> {
+          throw SpannerExceptionFactory.newSpannerException(e);
+        });
+  }
+
+  @Override
+  public OperationFuture<InstanceConfig, UpdateInstanceConfigMetadata> updateInstanceConfig(
+      InstanceConfigInfo instanceConfig,
+      Iterable<InstanceConfigInfo.InstanceConfigField> fieldsToUpdate,
+      UpdateAdminApiOption... options)
+      throws SpannerException {
+    final Options deleteAdminApiOptions = Options.fromAdminApiOptions(options);
+    FieldMask fieldMask = InstanceConfigInfo.InstanceConfigField.toFieldMask(fieldsToUpdate);
+
+    OperationFuture<
+            com.google.spanner.admin.instance.v1.InstanceConfig, UpdateInstanceConfigMetadata>
+        rawOperationFuture =
+            rpc.updateInstanceConfig(
+                instanceConfig.toProto(), deleteAdminApiOptions.validateOnly(), fieldMask);
+    return new OperationFutureImpl<>(
+        rawOperationFuture.getPollingFuture(),
+        rawOperationFuture.getInitialFuture(),
+        snapshot ->
+            InstanceConfig.fromProto(
+                ProtoOperationTransformers.ResponseTransformer.create(
+                        com.google.spanner.admin.instance.v1.InstanceConfig.class)
+                    .apply(snapshot),
+                InstanceAdminClientImpl.this),
+        ProtoOperationTransformers.MetadataTransformer.create(UpdateInstanceConfigMetadata.class),
+        e -> {
+          throw SpannerExceptionFactory.newSpannerException(e);
+        });
+  }
+
   @Override
   public InstanceConfig getInstanceConfig(String configId) throws SpannerException {
     String instanceConfigName = new InstanceConfigId(projectId, configId).getName();
@@ -67,6 +130,16 @@ public InstanceConfig getInstanceConfig(String configId) throws SpannerException
         rpc.getInstanceConfig(instanceConfigName), InstanceAdminClientImpl.this);
   }
 
+  @Override
+  public void deleteInstanceConfig(final String instanceConfigId, DeleteAdminApiOption... options)
+      throws SpannerException {
+    final Options deleteAdminApiOptions = Options.fromAdminApiOptions(options);
+    rpc.deleteInstanceConfig(
+        new InstanceConfigId(projectId, instanceConfigId).getName(),
+        deleteAdminApiOptions.etag(),
+        deleteAdminApiOptions.validateOnly());
+  }
+
   @Override
   public Page<InstanceConfig> listInstanceConfigs(ListOption... options) {
     final Options listOptions = Options.fromListOptions(options);
@@ -93,6 +166,30 @@ public InstanceConfig fromProto(
     return pageFetcher.getNextPage();
   }
 
+  @Override
+  public final Page<Operation> listInstanceConfigOperations(ListOption... options) {
+    final Options listOptions = Options.fromListOptions(options);
+    final int pageSize = listOptions.hasPageSize() ? listOptions.pageSize() : 0;
+    final String filter = listOptions.hasFilter() ? listOptions.filter() : null;
+
+    PageFetcher<Operation, Operation> pageFetcher =
+        new PageFetcher<Operation, Operation>() {
+          @Override
+          public Paginated<Operation> getNextPage(String nextPageToken) {
+            return rpc.listInstanceConfigOperations(pageSize, filter, nextPageToken);
+          }
+
+          @Override
+          public Operation fromProto(Operation proto) {
+            return proto;
+          }
+        };
+    if (listOptions.hasPageToken()) {
+      pageFetcher.setNextPageToken(listOptions.pageToken());
+    }
+    return pageFetcher.getNextPage();
+  }
+
   @Override
   public OperationFuture<Instance, CreateInstanceMetadata> createInstance(InstanceInfo instance)
       throws SpannerException {
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfig.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfig.java
index 6afbc028e1..9b96dda4df 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfig.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfig.java
@@ -18,7 +18,7 @@
 
 import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
+import java.util.Map;
 
 /**
  * Represents a Cloud Spanner instance config.{@code InstanceConfig} adds a layer of service related
@@ -28,10 +28,114 @@ public class InstanceConfig extends InstanceConfigInfo {
 
   private final InstanceAdminClient client;
 
+  /** Builder of {@code InstanceConfig}. */
+  public static class Builder extends InstanceConfigInfo.BuilderImpl {
+    private final InstanceAdminClient client;
+
+    Builder(InstanceConfig instanceConfig) {
+      super(instanceConfig);
+      this.client = instanceConfig.client;
+    }
+
+    Builder(InstanceAdminClient client, InstanceConfigId id) {
+      super(id);
+      this.client = client;
+    }
+
+    @Override
+    public Builder setDisplayName(String displayName) {
+      super.setDisplayName(displayName);
+      return this;
+    }
+
+    @Override
+    protected Builder setReplicas(List<ReplicaInfo> replicas) {
+      super.setReplicas(replicas);
+      return this;
+    }
+
+    @Override
+    public Builder setLeaderOptions(List<String> leaderOptions) {
+      super.setLeaderOptions(leaderOptions);
+      return this;
+    }
+
+    @Override
+    protected Builder setOptionalReplicas(List<ReplicaInfo> optionalReplicas) {
+      super.setOptionalReplicas(optionalReplicas);
+      return this;
+    }
+
+    @Override
+    protected Builder setBaseConfig(InstanceConfigInfo baseConfig) {
+      super.setBaseConfig(baseConfig);
+      return this;
+    }
+
+    @Override
+    protected Builder setConfigType(Type configType) {
+      super.setConfigType(configType);
+      return this;
+    }
+
+    @Override
+    protected Builder setState(State state) {
+      super.setState(state);
+      return this;
+    }
+
+    @Override
+    public Builder setEtag(String etag) {
+      super.setEtag(etag);
+      return this;
+    }
+
+    @Override
+    protected Builder setReconciling(boolean reconciling) {
+      super.setReconciling(reconciling);
+      return this;
+    }
+
+    @Override
+    public Builder addLabel(String key, String value) {
+      super.addLabel(key, value);
+      return this;
+    }
+
+    @Override
+    public Builder putAllLabels(Map<String, String> labels) {
+      super.putAllLabels(labels);
+      return this;
+    }
+
+    @Override
+    public Builder addReadOnlyReplicas(List<ReplicaInfo> readOnlyReplicas) {
+      super.addReadOnlyReplicas(readOnlyReplicas);
+      return this;
+    }
+
+    @Override
+    public InstanceConfig build() {
+      return new InstanceConfig(this);
+    }
+  }
+
+  public static Builder newBuilder(InstanceConfig instanceConfig) {
+    return new Builder(instanceConfig);
+  }
+
+  public static Builder newBuilder(InstanceAdminClient client, InstanceConfigId instanceConfigId) {
+    return new Builder(client, instanceConfigId);
+  }
+
+  /** Use {@link #newBuilder} instead */
+  @Deprecated
   public InstanceConfig(InstanceConfigId id, String displayName, InstanceAdminClient client) {
     this(id, displayName, Collections.emptyList(), Collections.emptyList(), client);
   }
 
+  /** Use {@link #newBuilder} instead */
+  @Deprecated
   public InstanceConfig(
       InstanceConfigId id,
       String displayName,
@@ -42,18 +146,18 @@ public InstanceConfig(
     this.client = client;
   }
 
+  InstanceConfig(Builder builder) {
+    super(builder);
+    this.client = builder.client;
+  }
+
   /** Gets the current state of this instance config. */
   public InstanceConfig reload() {
     return client.getInstanceConfig(getId().getInstanceConfig());
   }
 
-  static InstanceConfig fromProto(
-      com.google.spanner.admin.instance.v1.InstanceConfig proto, InstanceAdminClient client) {
-    return new InstanceConfig(
-        InstanceConfigId.of(proto.getName()),
-        proto.getDisplayName(),
-        proto.getReplicasList().stream().map(ReplicaInfo::fromProto).collect(Collectors.toList()),
-        proto.getLeaderOptionsList(),
-        client);
+  @Override
+  public Builder toBuilder() {
+    return new Builder(this);
   }
 }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java
index 43d4fbf953..f2b256fff4 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/InstanceConfigInfo.java
@@ -16,33 +16,72 @@
 
 package com.google.cloud.spanner;
 
-import java.util.Collections;
+import com.google.cloud.FieldSelector;
+import com.google.common.collect.ImmutableMap;
+import com.google.protobuf.FieldMask;
+import com.google.spanner.admin.instance.v1.InstanceConfig;
+import com.google.spanner.admin.instance.v1.InstanceConfig.State;
+import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 /** Represents a Cloud Spanner instance config resource. */
 public class InstanceConfigInfo {
 
-  private final InstanceConfigId id;
-  private final String displayName;
-  private final List<ReplicaInfo> replicas;
-  private final List<String> leaderOptions;
+  /** Represent an updatable field in Cloud Spanner InstanceConfig. */
+  public enum InstanceConfigField implements FieldSelector {
+    DISPLAY_NAME("display_name"),
+    LABELS("labels");
 
-  public InstanceConfigInfo(InstanceConfigId id, String displayName) {
-    this(id, displayName, Collections.emptyList(), Collections.emptyList());
+    private final String selector;
+
+    InstanceConfigField(String selector) {
+      this.selector = selector;
+    }
+
+    @Override
+    public String getSelector() {
+      return selector;
+    }
+
+    static FieldMask toFieldMask(Iterable<InstanceConfigField> fields) {
+      FieldMask.Builder builder = FieldMask.newBuilder();
+      for (InstanceConfigField field : fields) {
+        builder.addPaths(field.getSelector());
+      }
+      return builder.build();
+    }
   }
 
-  public InstanceConfigInfo(
-      InstanceConfigId id,
-      String displayName,
-      List<ReplicaInfo> replicas,
-      List<String> leaderOptions) {
-    this.id = id;
-    this.displayName = displayName;
-    this.replicas = replicas;
-    this.leaderOptions = leaderOptions;
+  /** Type of the Instance config. */
+  public enum Type {
+    TYPE_UNSPECIFIED,
+    GOOGLE_MANAGED,
+    USER_MANAGED
+  }
+
+  /** Type of the Instance config. */
+  public enum State {
+    STATE_UNSPECIFIED,
+    CREATING,
+    READY
   }
 
+  private final InstanceConfigId id;
+  private final String displayName;
+  private final List<ReplicaInfo> replicas;
+  private final List<String> leaderOptions;
+  private final List<ReplicaInfo> optionalReplicas;
+  private final InstanceConfigInfo baseConfig;
+  private final Type configType;
+  private final String etag;
+  private final boolean reconciling;
+  private final State state;
+  private final Map<String, String> labels;
+
   /** Returns the id of this instance config. */
   public InstanceConfigId getId() {
     return id;
@@ -69,6 +108,254 @@ public List<String> getLeaderOptions() {
     return leaderOptions;
   }
 
+  /**
+   * The available optional replicas to choose from for user managed configurations. Populated for
+   * Google managed configurations.
+   */
+  public List<ReplicaInfo> getOptionalReplicas() {
+    return optionalReplicas;
+  }
+
+  /**
+   * Base configuration, e.g. projects/<project_name>/instanceConfigs/nam3, based on which this
+   * configuration is created. Only set for user managed configurations. The base config must refer
+   * to a configuration of type GOOGLE_MANAGED.
+   */
+  public InstanceConfigInfo getBaseConfig() {
+    return baseConfig;
+  }
+
+  /**
+   * Config type, indicates whether this instance config is a Google or User Managed Configuration.
+   */
+  public Type getConfigType() {
+    return configType;
+  }
+
+  /**
+   * etag, which is used for optimistic concurrency control as a way to help prevent simultaneous
+   * updates of an instance config from overwriting each other.
+   */
+  public String getEtag() {
+    return etag;
+  }
+
+  /**
+   * If true, the instance config is being created or updated. If false, there are no ongoing
+   * operations for the instance config.
+   */
+  public boolean getReconciling() {
+    return reconciling;
+  }
+
+  /** The current instance config state. */
+  public State getState() {
+    return state;
+  }
+
+  /**
+   * Cloud Labels, which can be used to filter collections of resources. They can be used to control
+   * how resource metrics are aggregated.
+   */
+  public Map<String, String> getLabels() {
+    return labels;
+  }
+
+  /** Builder for {@code InstanceConfigInfo}. */
+  public abstract static class Builder {
+    public abstract Builder setDisplayName(String displayName);
+
+    protected abstract Builder setReplicas(List<ReplicaInfo> replicas);
+
+    protected abstract Builder setOptionalReplicas(List<ReplicaInfo> optionalReplicas);
+
+    protected abstract Builder setBaseConfig(InstanceConfigInfo baseConfig);
+
+    /**
+     * Sets the allowed values of the "default_leader" schema option for databases in instances that
+     * use this instance configuration.
+     */
+    public abstract Builder setLeaderOptions(List<String> leaderOptions);
+
+    protected abstract Builder setConfigType(Type configType);
+
+    protected abstract Builder setState(State state);
+
+    public abstract Builder setEtag(String etag);
+
+    protected abstract Builder setReconciling(boolean reconciling);
+
+    public abstract Builder addLabel(String key, String value);
+
+    public abstract Builder putAllLabels(Map<String, String> labels);
+
+    /**
+     * Adds the read only replicas to the set of replicas for a custom instance config. Called with
+     * one or more of the optional replicas of the base config.
+     */
+    public abstract Builder addReadOnlyReplicas(List<ReplicaInfo> readOnlyReplicas);
+
+    public abstract InstanceConfigInfo build();
+  }
+
+  static class BuilderImpl extends Builder {
+    private InstanceConfigId id;
+    private String displayName = "";
+    private List<ReplicaInfo> replicas = new ArrayList<>();
+    private List<String> leaderOptions = new ArrayList<>();
+    private List<ReplicaInfo> optionalReplicas = new ArrayList<>();
+    private InstanceConfigInfo baseConfig;
+    private Type configType = Type.TYPE_UNSPECIFIED;
+    private String etag = "";
+    private boolean reconciling = false;
+    private State state = State.STATE_UNSPECIFIED;
+    private Map<String, String> labels = new HashMap<>();
+
+    BuilderImpl(InstanceConfigId id) {
+      this.id = id;
+    }
+
+    BuilderImpl(InstanceConfigId id, InstanceConfigInfo baseConfig) {
+      this.id = id;
+      this.baseConfig = baseConfig;
+      this.replicas = new ArrayList<>(baseConfig.replicas);
+    }
+
+    BuilderImpl(InstanceConfigInfo instanceConfigInfo) {
+      this.id = instanceConfigInfo.id;
+      this.displayName = instanceConfigInfo.displayName;
+      this.replicas = new ArrayList<>(instanceConfigInfo.replicas);
+      this.leaderOptions = new ArrayList<>(instanceConfigInfo.leaderOptions);
+      this.optionalReplicas = new ArrayList<>(instanceConfigInfo.optionalReplicas);
+      this.baseConfig = instanceConfigInfo.baseConfig;
+      this.configType = instanceConfigInfo.configType;
+      this.etag = instanceConfigInfo.etag;
+      this.reconciling = instanceConfigInfo.reconciling;
+      this.state = instanceConfigInfo.state;
+      this.labels = new HashMap<>(instanceConfigInfo.labels);
+    }
+
+    @Override
+    public Builder setDisplayName(String displayName) {
+      this.displayName = displayName;
+      return this;
+    }
+
+    @Override
+    protected Builder setReplicas(List<ReplicaInfo> replicas) {
+      this.replicas = replicas;
+      return this;
+    }
+
+    @Override
+    public Builder setLeaderOptions(List<String> leaderOptions) {
+      this.leaderOptions = leaderOptions;
+      return this;
+    }
+
+    @Override
+    protected Builder setOptionalReplicas(List<ReplicaInfo> optionalReplicas) {
+      this.optionalReplicas = optionalReplicas;
+      return this;
+    }
+
+    @Override
+    protected Builder setBaseConfig(InstanceConfigInfo baseConfig) {
+      this.baseConfig = baseConfig;
+      return this;
+    }
+
+    @Override
+    protected Builder setConfigType(Type configType) {
+      this.configType = configType;
+      return this;
+    }
+
+    @Override
+    protected Builder setState(State state) {
+      this.state = state;
+      return this;
+    }
+
+    @Override
+    public Builder setEtag(String etag) {
+      this.etag = etag;
+      return this;
+    }
+
+    @Override
+    protected Builder setReconciling(boolean reconciling) {
+      this.reconciling = reconciling;
+      return this;
+    }
+
+    @Override
+    public Builder addLabel(String key, String value) {
+      this.labels.put(key, value);
+      return this;
+    }
+
+    @Override
+    public Builder putAllLabels(Map<String, String> labels) {
+      this.labels.putAll(labels);
+      return this;
+    }
+
+    @Override
+    public Builder addReadOnlyReplicas(List<ReplicaInfo> readOnlyReplicas) {
+      this.replicas.addAll(readOnlyReplicas);
+      return this;
+    }
+
+    @Override
+    public InstanceConfigInfo build() {
+      return new InstanceConfigInfo(this);
+    }
+  }
+
+  /** Use {@link #newBuilder} instead */
+  @Deprecated
+  public InstanceConfigInfo(InstanceConfigId id, String displayName) {
+    this((BuilderImpl) newBuilder(id).setDisplayName(displayName));
+  }
+
+  public static Builder newBuilder(InstanceConfigId id) {
+    return new BuilderImpl(id);
+  }
+
+  public static Builder newBuilder(InstanceConfigId id, InstanceConfigInfo baseConfig) {
+    return new BuilderImpl(id, baseConfig);
+  }
+
+  /** Use {@link #newBuilder} instead */
+  @Deprecated
+  public InstanceConfigInfo(
+      InstanceConfigId id,
+      String displayName,
+      List<ReplicaInfo> replicas,
+      List<String> leaderOptions) {
+    this(
+        (BuilderImpl)
+            newBuilder(id)
+                .setDisplayName(displayName)
+                .setReplicas(replicas)
+                .setLeaderOptions(leaderOptions));
+  }
+
+  InstanceConfigInfo(BuilderImpl builder) {
+    this.id = builder.id;
+    this.displayName = builder.displayName;
+    this.replicas = new ArrayList<>(builder.replicas);
+    this.leaderOptions = new ArrayList<>(builder.leaderOptions);
+    this.baseConfig = builder.baseConfig;
+    this.optionalReplicas = new ArrayList<>(builder.optionalReplicas);
+    this.configType = builder.configType;
+    this.etag = builder.etag;
+    this.reconciling = builder.reconciling;
+    this.state = builder.state;
+    this.labels = ImmutableMap.copyOf(builder.labels);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) {
@@ -81,17 +368,157 @@ public boolean equals(Object o) {
     return Objects.equals(id, that.id)
         && Objects.equals(displayName, that.displayName)
         && Objects.equals(replicas, that.replicas)
-        && Objects.equals(leaderOptions, that.leaderOptions);
+        && Objects.equals(leaderOptions, that.leaderOptions)
+        && Objects.equals(optionalReplicas, that.optionalReplicas)
+        && Objects.equals(baseConfig, that.baseConfig)
+        && Objects.equals(configType, that.configType)
+        && Objects.equals(etag, that.etag)
+        && Objects.equals(reconciling, that.reconciling)
+        && Objects.equals(state, that.state)
+        && Objects.equals(labels, that.labels);
   }
 
   @Override
   public int hashCode() {
-    return Objects.hash(id, displayName, replicas, leaderOptions);
+    return Objects.hash(
+        id,
+        displayName,
+        replicas,
+        leaderOptions,
+        optionalReplicas,
+        baseConfig,
+        configType,
+        etag,
+        reconciling,
+        state,
+        labels);
+  }
+
+  public Builder toBuilder() {
+    return new BuilderImpl(this);
   }
 
   @Override
   public String toString() {
     return String.format(
-        "Instance Config[%s, %s, %s, %s]", id, displayName, replicas, leaderOptions);
+        "Instance Config[%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s]",
+        id,
+        displayName,
+        replicas,
+        leaderOptions,
+        optionalReplicas,
+        baseConfig,
+        configType,
+        etag,
+        reconciling,
+        state,
+        labels);
+  }
+
+  com.google.spanner.admin.instance.v1.InstanceConfig toProto() {
+    InstanceConfig.Builder builder =
+        com.google.spanner.admin.instance.v1.InstanceConfig.newBuilder()
+            .setName(getId().getName())
+            .setDisplayName(getDisplayName())
+            .addAllReplicas(
+                getReplicas().stream().map(ReplicaInfo::getProto).collect(Collectors.toList()))
+            .addAllLeaderOptions(getLeaderOptions())
+            .setEtag(getEtag())
+            .setReconciling(getReconciling())
+            .putAllLabels(getLabels())
+            .addAllOptionalReplicas(
+                getOptionalReplicas().stream()
+                    .map(ReplicaInfo::getProto)
+                    .collect(Collectors.toList()))
+            .setConfigType(toProtoConfigType(getConfigType()))
+            .setState(toProtoState(getState()));
+
+    if (getBaseConfig() != null) {
+      builder.setBaseConfig(getBaseConfig().getId().getName());
+    }
+
+    return builder.build();
+  }
+
+  private static InstanceConfig.Type toProtoConfigType(Type type) {
+    switch (type) {
+      case TYPE_UNSPECIFIED:
+        return com.google.spanner.admin.instance.v1.InstanceConfig.Type.TYPE_UNSPECIFIED;
+      case GOOGLE_MANAGED:
+        return com.google.spanner.admin.instance.v1.InstanceConfig.Type.GOOGLE_MANAGED;
+      case USER_MANAGED:
+        return InstanceConfig.Type.USER_MANAGED;
+      default:
+        throw new IllegalArgumentException("Unknown config type:" + type);
+    }
+  }
+
+  private static InstanceConfig.State toProtoState(State state) {
+    switch (state) {
+      case STATE_UNSPECIFIED:
+        return com.google.spanner.admin.instance.v1.InstanceConfig.State.STATE_UNSPECIFIED;
+      case CREATING:
+        return com.google.spanner.admin.instance.v1.InstanceConfig.State.CREATING;
+      case READY:
+        return com.google.spanner.admin.instance.v1.InstanceConfig.State.READY;
+      default:
+        throw new IllegalArgumentException("Unknown state:" + state);
+    }
+  }
+
+  static com.google.cloud.spanner.InstanceConfig fromProto(
+      com.google.spanner.admin.instance.v1.InstanceConfig proto, InstanceAdminClient client) {
+    com.google.cloud.spanner.InstanceConfig.Builder builder =
+        com.google.cloud.spanner.InstanceConfig.newBuilder(
+                client, InstanceConfigId.of(proto.getName()))
+            .setReconciling(proto.getReconciling())
+            .setReplicas(
+                proto.getReplicasList().stream()
+                    .map(ReplicaInfo::fromProto)
+                    .collect(Collectors.toList()))
+            .setDisplayName(proto.getDisplayName())
+            .putAllLabels(proto.getLabelsMap())
+            .setEtag(proto.getEtag())
+            .setLeaderOptions(proto.getLeaderOptionsList())
+            .setOptionalReplicas(
+                proto.getOptionalReplicasList().stream()
+                    .map(ReplicaInfo::fromProto)
+                    .collect(Collectors.toList()))
+            .setState(fromProtoState(proto.getState()))
+            .setConfigType(fromProtoConfigType(proto.getConfigType()));
+
+    if (!proto.getBaseConfig().isEmpty()) {
+      builder.setBaseConfig(newBuilder(InstanceConfigId.of(proto.getBaseConfig())).build());
+    }
+
+    return builder.build();
+  }
+
+  private static State fromProtoState(
+      com.google.spanner.admin.instance.v1.InstanceConfig.State state) {
+    switch (state) {
+      case STATE_UNSPECIFIED:
+        return State.STATE_UNSPECIFIED;
+      case CREATING:
+        return State.CREATING;
+      case READY:
+        return State.READY;
+      default:
+        throw new IllegalArgumentException("Unknown state:" + state);
+    }
+  }
+
+  private static Type fromProtoConfigType(
+      com.google.spanner.admin.instance.v1.InstanceConfig.Type type) {
+    switch (type) {
+      case TYPE_UNSPECIFIED:
+        return Type.TYPE_UNSPECIFIED;
+      case GOOGLE_MANAGED:
+        return Type.GOOGLE_MANAGED;
+      case USER_MANAGED:
+        return Type.USER_MANAGED;
+      default:
+        throw new IllegalArgumentException("Unknown config type:" + type);
+    }
   }
 }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/Options.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/Options.java
index fa2cd2526e..7b411b4caa 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/Options.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/Options.java
@@ -51,6 +51,22 @@ public interface ReadOption {}
   public interface ReadQueryUpdateTransactionOption
       extends ReadOption, QueryOption, UpdateOption, TransactionOption {}
 
+  /**
+   * Marker interface to mark options applicable to Create, Update and Delete operations in admin
+   * API.
+   */
+  public interface CreateUpdateDeleteAdminApiOption
+      extends CreateAdminApiOption, UpdateAdminApiOption, DeleteAdminApiOption {}
+
+  /** Marker interface to mark options applicable to Create operations in admin API. */
+  public interface CreateAdminApiOption extends AdminApiOption {}
+
+  /** Marker interface to mark options applicable to Delete operations in admin API. */
+  public interface DeleteAdminApiOption extends AdminApiOption {}
+
+  /** Marker interface to mark options applicable to Update operations in admin API. */
+  public interface UpdateAdminApiOption extends AdminApiOption {}
+
   /** Marker interface to mark options applicable to query operation. */
   public interface QueryOption {}
 
@@ -63,6 +79,9 @@ public interface UpdateOption {}
   /** Marker interface to mark options applicable to list operations in admin API. */
   public interface ListOption {}
 
+  /** Marker interface to mark options applicable to operations in admin API. */
+  public interface AdminApiOption {}
+
   /** Specifying this instructs the transaction to request {@link CommitStats} from the backend. */
   public static TransactionOption commitStats() {
     return COMMIT_STATS_OPTION;
@@ -151,6 +170,33 @@ public static ListOption filter(String filter) {
     return new FilterOption(filter);
   }
 
+  /**
+   * Specifying this will help in optimistic concurrency control as a way to help prevent
+   * simultaneous deletes of an instance config from overwriting each other. Operations that support
+   * this option are:
+   *
+   * <ul>
+   *   <li>{@link InstanceAdminClient#deleteInstanceConfig}
+   * </ul>
+   */
+  public static DeleteAdminApiOption etag(String etag) {
+    return new EtagOption(etag);
+  }
+
+  /**
+   * Specifying this will not actually execute a request, and provide the same response. Operations
+   * that support this option are:
+   *
+   * <ul>
+   *   <li>{@link InstanceAdminClient#createInstanceConfig}
+   *   <li>{@link InstanceAdminClient#updateInstanceConfig}
+   *   <li>{@link InstanceAdminClient#deleteInstanceConfig}
+   * </ul>
+   */
+  public static CreateUpdateDeleteAdminApiOption validateOnly(Boolean validateOnly) {
+    return new ValidateOnlyOption(validateOnly);
+  }
+
   /** Option to request {@link CommitStats} for read/write transactions. */
   static final class CommitStatsOption extends InternalOption implements TransactionOption {
     @Override
@@ -215,6 +261,33 @@ void appendToOptions(Options options) {
     }
   }
 
+  static final class EtagOption extends InternalOption implements DeleteAdminApiOption {
+    private final String etag;
+
+    EtagOption(String etag) {
+      this.etag = etag;
+    }
+
+    @Override
+    void appendToOptions(Options options) {
+      options.etag = etag;
+    }
+  }
+
+  static final class ValidateOnlyOption extends InternalOption
+      implements CreateUpdateDeleteAdminApiOption {
+    private final Boolean validateOnly;
+
+    ValidateOnlyOption(Boolean validateOnly) {
+      this.validateOnly = validateOnly;
+    }
+
+    @Override
+    void appendToOptions(Options options) {
+      options.validateOnly = validateOnly;
+    }
+  }
+
   private boolean withCommitStats;
   private Long limit;
   private Integer prefetchChunks;
@@ -224,6 +297,8 @@ void appendToOptions(Options options) {
   private String filter;
   private RpcPriority priority;
   private String tag;
+  private String etag;
+  private Boolean validateOnly;
 
   // Construction is via factory methods below.
   private Options() {}
@@ -296,6 +371,22 @@ String tag() {
     return tag;
   }
 
+  boolean hasEtag() {
+    return etag != null;
+  }
+
+  String etag() {
+    return etag;
+  }
+
+  boolean hasValidateOnly() {
+    return validateOnly != null;
+  }
+
+  Boolean validateOnly() {
+    return validateOnly;
+  }
+
   @Override
   public String toString() {
     StringBuilder b = new StringBuilder();
@@ -323,6 +414,12 @@ public String toString() {
     if (tag != null) {
       b.append("tag: ").append(tag).append(' ');
     }
+    if (etag != null) {
+      b.append("etag: ").append(etag).append(' ');
+    }
+    if (validateOnly != null) {
+      b.append("validateOnly: ").append(validateOnly).append(' ');
+    }
     return b.toString();
   }
 
@@ -354,7 +451,9 @@ public boolean equals(Object o) {
         && Objects.equals(pageToken(), that.pageToken())
         && Objects.equals(filter(), that.filter())
         && Objects.equals(priority(), that.priority())
-        && Objects.equals(tag(), that.tag());
+        && Objects.equals(tag(), that.tag())
+        && Objects.equals(etag(), that.etag())
+        && Objects.equals(validateOnly(), that.validateOnly());
   }
 
   @Override
@@ -387,6 +486,12 @@ public int hashCode() {
     if (tag != null) {
       result = 31 * result + tag.hashCode();
     }
+    if (etag != null) {
+      result = 31 * result + etag.hashCode();
+    }
+    if (validateOnly != null) {
+      result = 31 * result + validateOnly.hashCode();
+    }
     return result;
   }
 
@@ -440,6 +545,16 @@ static Options fromListOptions(ListOption... options) {
     return listOptions;
   }
 
+  static Options fromAdminApiOptions(AdminApiOption... options) {
+    Options adminApiOptions = new Options();
+    for (AdminApiOption option : options) {
+      if (option instanceof InternalOption) {
+        ((InternalOption) option).appendToOptions(adminApiOptions);
+      }
+    }
+    return adminApiOptions;
+  }
+
   private abstract static class InternalOption {
     abstract void appendToOptions(Options options);
   }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/GapicSpannerRpc.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/GapicSpannerRpc.java
index 937da7e8d2..3f28d46c1c 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/GapicSpannerRpc.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/GapicSpannerRpc.java
@@ -133,18 +133,25 @@
 import com.google.spanner.admin.database.v1.UpdateBackupRequest;
 import com.google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata;
 import com.google.spanner.admin.database.v1.UpdateDatabaseDdlRequest;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigMetadata;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigRequest;
 import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
 import com.google.spanner.admin.instance.v1.CreateInstanceRequest;
+import com.google.spanner.admin.instance.v1.DeleteInstanceConfigRequest;
 import com.google.spanner.admin.instance.v1.DeleteInstanceRequest;
 import com.google.spanner.admin.instance.v1.GetInstanceConfigRequest;
 import com.google.spanner.admin.instance.v1.GetInstanceRequest;
 import com.google.spanner.admin.instance.v1.Instance;
 import com.google.spanner.admin.instance.v1.InstanceAdminGrpc;
 import com.google.spanner.admin.instance.v1.InstanceConfig;
+import com.google.spanner.admin.instance.v1.ListInstanceConfigOperationsRequest;
+import com.google.spanner.admin.instance.v1.ListInstanceConfigOperationsResponse;
 import com.google.spanner.admin.instance.v1.ListInstanceConfigsRequest;
 import com.google.spanner.admin.instance.v1.ListInstanceConfigsResponse;
 import com.google.spanner.admin.instance.v1.ListInstancesRequest;
 import com.google.spanner.admin.instance.v1.ListInstancesResponse;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigMetadata;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigRequest;
 import com.google.spanner.admin.instance.v1.UpdateInstanceMetadata;
 import com.google.spanner.admin.instance.v1.UpdateInstanceRequest;
 import com.google.spanner.v1.BatchCreateSessionsRequest;
@@ -879,6 +886,48 @@ public Paginated<InstanceConfig> listInstanceConfigs(int pageSize, @Nullable Str
     return new Paginated<>(response.getInstanceConfigsList(), response.getNextPageToken());
   }
 
+  @Override
+  public OperationFuture<InstanceConfig, CreateInstanceConfigMetadata> createInstanceConfig(
+      String parent,
+      String instanceConfigId,
+      InstanceConfig instanceConfig,
+      @Nullable Boolean validateOnly)
+      throws SpannerException {
+    CreateInstanceConfigRequest.Builder builder =
+        CreateInstanceConfigRequest.newBuilder()
+            .setParent(parent)
+            .setInstanceConfigId(instanceConfigId)
+            .setInstanceConfig(instanceConfig);
+    if (validateOnly != null) {
+      builder.setValidateOnly(validateOnly);
+    }
+    CreateInstanceConfigRequest request = builder.build();
+    GrpcCallContext context =
+        newCallContext(null, parent, request, InstanceAdminGrpc.getCreateInstanceConfigMethod());
+    return instanceAdminStub.createInstanceConfigOperationCallable().futureCall(request, context);
+  }
+
+  @Override
+  public OperationFuture<InstanceConfig, UpdateInstanceConfigMetadata> updateInstanceConfig(
+      InstanceConfig instanceConfig, @Nullable Boolean validateOnly, FieldMask fieldMask)
+      throws SpannerException {
+    UpdateInstanceConfigRequest.Builder builder =
+        UpdateInstanceConfigRequest.newBuilder()
+            .setInstanceConfig(instanceConfig)
+            .setUpdateMask(fieldMask);
+    if (validateOnly != null) {
+      builder.setValidateOnly(validateOnly);
+    }
+    UpdateInstanceConfigRequest request = builder.build();
+    GrpcCallContext context =
+        newCallContext(
+            null,
+            instanceConfig.getName(),
+            request,
+            InstanceAdminGrpc.getUpdateInstanceConfigMethod());
+    return instanceAdminStub.updateInstanceConfigOperationCallable().futureCall(request, context);
+  }
+
   @Override
   public InstanceConfig getInstanceConfig(String instanceConfigName) throws SpannerException {
     GetInstanceConfigRequest request =
@@ -889,6 +938,55 @@ public InstanceConfig getInstanceConfig(String instanceConfigName) throws Spanne
     return get(instanceAdminStub.getInstanceConfigCallable().futureCall(request, context));
   }
 
+  @Override
+  public void deleteInstanceConfig(
+      String instanceConfigName, @Nullable String etag, @Nullable Boolean validateOnly)
+      throws SpannerException {
+    DeleteInstanceConfigRequest.Builder requestBuilder =
+        DeleteInstanceConfigRequest.newBuilder().setName(instanceConfigName);
+
+    if (etag != null) {
+      requestBuilder.setEtag(etag);
+    }
+    if (validateOnly != null) {
+      requestBuilder.setValidateOnly(validateOnly);
+    }
+    DeleteInstanceConfigRequest request = requestBuilder.build();
+    GrpcCallContext context =
+        newCallContext(
+            null, instanceConfigName, request, InstanceAdminGrpc.getDeleteInstanceConfigMethod());
+    get(instanceAdminStub.deleteInstanceConfigCallable().futureCall(request, context));
+  }
+
+  @Override
+  public Paginated<Operation> listInstanceConfigOperations(
+      int pageSize, @Nullable String filter, @Nullable String pageToken) {
+    acquireAdministrativeRequestsRateLimiter();
+    ListInstanceConfigOperationsRequest.Builder requestBuilder =
+        ListInstanceConfigOperationsRequest.newBuilder()
+            .setParent(projectName)
+            .setPageSize(pageSize);
+    if (filter != null) {
+      requestBuilder.setFilter(filter);
+    }
+    if (pageToken != null) {
+      requestBuilder.setPageToken(pageToken);
+    }
+    final ListInstanceConfigOperationsRequest request = requestBuilder.build();
+
+    final GrpcCallContext context =
+        newCallContext(
+            null, projectName, request, InstanceAdminGrpc.getListInstanceConfigOperationsMethod());
+    ListInstanceConfigOperationsResponse response =
+        runWithRetryOnAdministrativeRequestsExceeded(
+            () ->
+                get(
+                    instanceAdminStub
+                        .listInstanceConfigOperationsCallable()
+                        .futureCall(request, context)));
+    return new Paginated<>(response.getOperationsList(), response.getNextPageToken());
+  }
+
   @Override
   public Paginated<Instance> listInstances(
       int pageSize, @Nullable String pageToken, @Nullable String filter) throws SpannerException {
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/SpannerRpc.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/SpannerRpc.java
index 189af2fb55..2f68b9c1df 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/SpannerRpc.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/SpannerRpc.java
@@ -34,10 +34,19 @@
 import com.google.longrunning.Operation;
 import com.google.protobuf.Empty;
 import com.google.protobuf.FieldMask;
-import com.google.spanner.admin.database.v1.*;
+import com.google.spanner.admin.database.v1.Backup;
+import com.google.spanner.admin.database.v1.CopyBackupMetadata;
+import com.google.spanner.admin.database.v1.CreateBackupMetadata;
+import com.google.spanner.admin.database.v1.CreateDatabaseMetadata;
+import com.google.spanner.admin.database.v1.Database;
+import com.google.spanner.admin.database.v1.DatabaseRole;
+import com.google.spanner.admin.database.v1.RestoreDatabaseMetadata;
+import com.google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
 import com.google.spanner.admin.instance.v1.Instance;
 import com.google.spanner.admin.instance.v1.InstanceConfig;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.UpdateInstanceMetadata;
 import com.google.spanner.v1.*;
 import java.util.List;
@@ -162,8 +171,35 @@ interface StreamingCall {
   Paginated<InstanceConfig> listInstanceConfigs(int pageSize, @Nullable String pageToken)
       throws SpannerException;
 
+  default OperationFuture<InstanceConfig, CreateInstanceConfigMetadata> createInstanceConfig(
+      String parent,
+      String instanceConfigId,
+      InstanceConfig instanceConfig,
+      @Nullable Boolean validateOnly)
+      throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
+  default OperationFuture<InstanceConfig, UpdateInstanceConfigMetadata> updateInstanceConfig(
+      InstanceConfig instanceConfig, @Nullable Boolean validateOnly, FieldMask fieldMask)
+      throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
   InstanceConfig getInstanceConfig(String instanceConfigName) throws SpannerException;
 
+  default void deleteInstanceConfig(
+      String instanceConfigName, @Nullable String etag, @Nullable Boolean validateOnly)
+      throws SpannerException {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
+  /** List all long-running instance config operations on the given project. */
+  default Paginated<Operation> listInstanceConfigOperations(
+      int pageSize, @Nullable String filter, @Nullable String pageToken) {
+    throw new UnsupportedOperationException("Not implemented");
+  }
+
   Paginated<Instance> listInstances(
       int pageSize, @Nullable String pageToken, @Nullable String filter) throws SpannerException;
 
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceAdminClientImplTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceAdminClientImplTest.java
index 0df869de67..d8134ef29d 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceAdminClientImplTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceAdminClientImplTest.java
@@ -27,6 +27,7 @@
 import com.google.api.gax.longrunning.OperationFuture;
 import com.google.cloud.Identity;
 import com.google.cloud.Role;
+import com.google.cloud.spanner.InstanceConfigInfo.InstanceConfigField;
 import com.google.cloud.spanner.spi.v1.SpannerRpc;
 import com.google.cloud.spanner.spi.v1.SpannerRpc.Paginated;
 import com.google.common.collect.ImmutableList;
@@ -36,10 +37,14 @@
 import com.google.iam.v1.Binding;
 import com.google.iam.v1.Policy;
 import com.google.iam.v1.TestIamPermissionsResponse;
+import com.google.longrunning.Operation;
+import com.google.protobuf.Any;
 import com.google.protobuf.ByteString;
 import com.google.protobuf.FieldMask;
+import com.google.spanner.admin.instance.v1.CreateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
 import com.google.spanner.admin.instance.v1.InstanceConfig;
+import com.google.spanner.admin.instance.v1.UpdateInstanceConfigMetadata;
 import com.google.spanner.admin.instance.v1.UpdateInstanceMetadata;
 import java.util.Arrays;
 import java.util.List;
@@ -59,6 +64,7 @@ public class InstanceAdminClientImplTest {
   private static final String CONFIG_ID = "my-config";
   private static final String CONFIG_NAME = "projects/my-project/instanceConfigs/my-config";
   private static final String CONFIG_NAME2 = "projects/my-project/instanceConfigs/my-config2";
+  private static final String BASE_CONFIG = "projects/my-project/instanceConfigs/my-base-config";
 
   @Mock SpannerRpc rpc;
   @Mock DatabaseAdminClient dbClient;
@@ -70,6 +76,84 @@ public void setUp() {
     client = new InstanceAdminClientImpl(PROJECT_ID, rpc, dbClient);
   }
 
+  private List<com.google.spanner.admin.instance.v1.ReplicaInfo> getAllReplicas() {
+    return Arrays.asList(
+        com.google.spanner.admin.instance.v1.ReplicaInfo.newBuilder()
+            .setLocation("Replica Location 1")
+            .setType(com.google.spanner.admin.instance.v1.ReplicaInfo.ReplicaType.READ_WRITE)
+            .setDefaultLeaderLocation(true)
+            .build(),
+        com.google.spanner.admin.instance.v1.ReplicaInfo.newBuilder()
+            .setLocation("Replica Location 2")
+            .setType(com.google.spanner.admin.instance.v1.ReplicaInfo.ReplicaType.READ_ONLY)
+            .setDefaultLeaderLocation(false)
+            .build(),
+        com.google.spanner.admin.instance.v1.ReplicaInfo.newBuilder()
+            .setLocation("Replica Location 3")
+            .setType(com.google.spanner.admin.instance.v1.ReplicaInfo.ReplicaType.WITNESS)
+            .setDefaultLeaderLocation(false)
+            .build());
+  }
+
+  private com.google.spanner.admin.instance.v1.InstanceConfig getInstanceConfigProto() {
+    return com.google.spanner.admin.instance.v1.InstanceConfig.newBuilder()
+        .setName(CONFIG_NAME)
+        .setBaseConfig(BASE_CONFIG)
+        .addAllReplicas(getAllReplicas())
+        .build();
+  }
+
+  @Test
+  public void createInstanceConfig() {
+    OperationFuture<
+            com.google.spanner.admin.instance.v1.InstanceConfig, CreateInstanceConfigMetadata>
+        rawOperationFuture =
+            OperationFutureUtil.immediateOperationFuture(
+                "createInstanceConfig",
+                getInstanceConfigProto(),
+                CreateInstanceConfigMetadata.getDefaultInstance());
+    when(rpc.createInstanceConfig(
+            "projects/" + PROJECT_ID, CONFIG_ID, getInstanceConfigProto(), false))
+        .thenReturn(rawOperationFuture);
+
+    InstanceConfigInfo instanceConfigInfo =
+        InstanceConfigInfo.fromProto(getInstanceConfigProto(), client);
+
+    OperationFuture<com.google.cloud.spanner.InstanceConfig, CreateInstanceConfigMetadata> op =
+        client.createInstanceConfig(instanceConfigInfo, Options.validateOnly(false));
+    assertThat(op.isDone()).isTrue();
+  }
+
+  @Test
+  public void updateInstanceConfig() throws Exception {
+    com.google.spanner.admin.instance.v1.InstanceConfig instanceConfig =
+        com.google.spanner.admin.instance.v1.InstanceConfig.newBuilder()
+            .setName(CONFIG_NAME)
+            .setDisplayName(CONFIG_NAME)
+            .build();
+    OperationFuture<
+            com.google.spanner.admin.instance.v1.InstanceConfig, UpdateInstanceConfigMetadata>
+        rawOperationFuture =
+            OperationFutureUtil.immediateOperationFuture(
+                "updateInstanceConfig",
+                getInstanceConfigProto(),
+                UpdateInstanceConfigMetadata.getDefaultInstance());
+    when(rpc.updateInstanceConfig(
+            instanceConfig, false, FieldMask.newBuilder().addPaths("display_name").build()))
+        .thenReturn(rawOperationFuture);
+    InstanceConfigInfo instanceConfigInfo =
+        InstanceConfigInfo.newBuilder(InstanceConfigId.of(CONFIG_NAME))
+            .setDisplayName(CONFIG_NAME)
+            .build();
+    OperationFuture<com.google.cloud.spanner.InstanceConfig, UpdateInstanceConfigMetadata> op =
+        client.updateInstanceConfig(
+            instanceConfigInfo,
+            ImmutableList.of(InstanceConfigField.DISPLAY_NAME),
+            Options.validateOnly(false));
+    assertThat(op.isDone()).isTrue();
+    assertThat(op.get().getId().getName()).isEqualTo(CONFIG_NAME);
+  }
+
   @Test
   public void getInstanceConfig() {
     when(rpc.getInstanceConfig(CONFIG_NAME))
@@ -77,6 +161,51 @@ public void getInstanceConfig() {
     assertThat(client.getInstanceConfig(CONFIG_ID).getId().getName()).isEqualTo(CONFIG_NAME);
   }
 
+  @Test
+  public void dropInstanceConfig() {
+    client.deleteInstanceConfig(CONFIG_ID);
+    verify(rpc).deleteInstanceConfig(CONFIG_NAME, null, null);
+  }
+
+  public Operation getInstanceConfigOperation(String instanceConfigId, Integer operationId) {
+    InstanceConfig instanceConfig =
+        com.google.spanner.admin.instance.v1.InstanceConfig.newBuilder()
+            .setName(instanceConfigId)
+            .setBaseConfig(BASE_CONFIG)
+            .addAllReplicas(getAllReplicas())
+            .build();
+
+    CreateInstanceConfigMetadata metadata =
+        CreateInstanceConfigMetadata.newBuilder().setInstanceConfig(instanceConfig).build();
+
+    final String operationName =
+        String.format(
+            "projects/%s/instanceConfigs/%s/operations/%d",
+            PROJECT_ID, instanceConfigId, operationId);
+    return com.google.longrunning.Operation.newBuilder()
+        .setMetadata(Any.pack(metadata))
+        .setResponse(Any.pack(instanceConfig))
+        .setDone(false)
+        .setName(operationName)
+        .build();
+  }
+
+  @Test
+  public void listInstanceConfigOperations() {
+    String nextToken = "token";
+    Operation operation1 = getInstanceConfigOperation("custom-instance-config-1", 1);
+    Operation operation2 = getInstanceConfigOperation("custom-instance-config-2", 2);
+    when(rpc.listInstanceConfigOperations(1, null, null))
+        .thenReturn(new Paginated<>(ImmutableList.of(operation1), nextToken));
+    when(rpc.listInstanceConfigOperations(1, null, nextToken))
+        .thenReturn(new Paginated<>(ImmutableList.of(operation2), ""));
+    List<Operation> operations =
+        Lists.newArrayList(client.listInstanceConfigOperations(Options.pageSize(1)).iterateAll());
+    assertThat(operations.get(0).getName()).isEqualTo(operation1.getName());
+    assertThat(operations.get(1).getName()).isEqualTo(operation2.getName());
+    assertThat(operations.size()).isEqualTo(2);
+  }
+
   @Test
   public void listInstanceConfigs() {
     String nextToken = "token";
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceConfigTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceConfigTest.java
index 3b0f56c088..234c322f76 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceConfigTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/InstanceConfigTest.java
@@ -40,6 +40,19 @@ public void testInstanceConfigFromProto() {
             com.google.spanner.admin.instance.v1.InstanceConfig.newBuilder()
                 .setDisplayName("Display Name")
                 .setName("projects/my-project/instanceConfigs/my-instance-config")
+                .setBaseConfig("projects/my-project/instanceConfigs/custom-base-config")
+                .addAllOptionalReplicas(
+                    Arrays.asList(
+                        com.google.spanner.admin.instance.v1.ReplicaInfo.newBuilder()
+                            .setLocation("Optional Replica Location 1")
+                            .setType(ReplicaType.READ_ONLY)
+                            .setDefaultLeaderLocation(true)
+                            .build(),
+                        com.google.spanner.admin.instance.v1.ReplicaInfo.newBuilder()
+                            .setLocation("Optional Replica Location 2")
+                            .setType(ReplicaType.READ_ONLY)
+                            .setDefaultLeaderLocation(false)
+                            .build()))
                 .addAllLeaderOptions(Arrays.asList("Leader Option 1", "Leader Option 2"))
                 .addAllReplicas(
                     Arrays.asList(
@@ -63,26 +76,43 @@ public void testInstanceConfigFromProto() {
 
     assertEquals(
         new InstanceConfig(
-            InstanceConfigId.of("my-project", "my-instance-config"),
-            "Display Name",
-            Arrays.asList(
-                ReplicaInfo.newBuilder()
-                    .setLocation("Replica Location 1")
-                    .setType(ReplicaInfo.ReplicaType.READ_WRITE)
-                    .setDefaultLeaderLocation(true)
-                    .build(),
-                ReplicaInfo.newBuilder()
-                    .setLocation("Replica Location 2")
-                    .setType(ReplicaInfo.ReplicaType.READ_ONLY)
-                    .setDefaultLeaderLocation(false)
-                    .build(),
-                ReplicaInfo.newBuilder()
-                    .setLocation("Replica Location 3")
-                    .setType(ReplicaInfo.ReplicaType.WITNESS)
-                    .setDefaultLeaderLocation(false)
-                    .build()),
-            Arrays.asList("Leader Option 1", "Leader Option 2"),
-            client),
+            new InstanceConfig.Builder(
+                    client, InstanceConfigId.of("my-project", "my-instance-config"))
+                .setDisplayName("Display Name")
+                .setReplicas(
+                    Arrays.asList(
+                        ReplicaInfo.newBuilder()
+                            .setLocation("Replica Location 1")
+                            .setType(ReplicaInfo.ReplicaType.READ_WRITE)
+                            .setDefaultLeaderLocation(true)
+                            .build(),
+                        ReplicaInfo.newBuilder()
+                            .setLocation("Replica Location 2")
+                            .setType(ReplicaInfo.ReplicaType.READ_ONLY)
+                            .setDefaultLeaderLocation(false)
+                            .build(),
+                        ReplicaInfo.newBuilder()
+                            .setLocation("Replica Location 3")
+                            .setType(ReplicaInfo.ReplicaType.WITNESS)
+                            .setDefaultLeaderLocation(false)
+                            .build()))
+                .setLeaderOptions(Arrays.asList("Leader Option 1", "Leader Option 2"))
+                .setOptionalReplicas(
+                    Arrays.asList(
+                        ReplicaInfo.newBuilder()
+                            .setLocation("Optional Replica Location 1")
+                            .setType(ReplicaInfo.ReplicaType.READ_ONLY)
+                            .setDefaultLeaderLocation(true)
+                            .build(),
+                        ReplicaInfo.newBuilder()
+                            .setLocation("Optional Replica Location 2")
+                            .setType(ReplicaInfo.ReplicaType.READ_ONLY)
+                            .setDefaultLeaderLocation(false)
+                            .build()))
+                .setBaseConfig(
+                    new InstanceConfigInfo.BuilderImpl(
+                            InstanceConfigId.of("my-project", "custom-base-config"))
+                        .build())),
         instanceConfig);
   }