feat(cloud_sql): Add samples for Advanced DR switchover for MySQL and PostgreSQL (terraform-google-modules#814)

* feat: Add MySQL & PostgreSQL samples for Advanced DR switchover

* Fix region tag

* Update test.yaml

Fix tag name

* Update test.yaml

update tag name

* Update test.yaml

update tag name

* lint: whitespace

* lint: whitespace

* Remove unnecessary comments

* Remove unnecessary comments

* Remove unnecessary comments

* linting

* lint

---------

Co-authored-by: Katie McLaughlin <[email protected]>

Author: 2 people

cloud_sql/mysql_instance_switchover/dr_replica_create/main.tf

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+/**
+ * Copyright 2025 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
+ * limitations under the License.
+ */
+
+
+# [START cloud_sql_mysql_instance_switchover_dr_replica_create]
+resource "google_sql_database_instance" "original-primary" {
+  name   = "mysql-original-primary-instance"
+  region = "us-east1"
+  # Specify a database version that supports Cloud SQL Enterprise Plus edition.
+  database_version = "MYSQL_8_0"
+  instance_type    = "CLOUD_SQL_INSTANCE"
+
+  settings {
+    # Specify a tier that supports Cloud SQL Enterprise Plus edition.
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      # You must enable automated backups and binary logging.
+      enabled            = true
+      binary_log_enabled = true
+    }
+  }
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+}
+
+resource "google_sql_database_instance" "dr-replica" {
+  name = "mysql-dr-replica-instance"
+  # DR replica must be in a different region than the region of the primary instance.
+  region = "us-west2"
+  # DR replica must be the same database version as the primary instance.
+  database_version = "MYSQL_8_0"
+  instance_type    = "READ_REPLICA_INSTANCE"
+  # Specify the primary instance as the master instance.
+  master_instance_name = google_sql_database_instance.original-primary.name
+
+  settings {
+    # DR replica must be in the same tier as your primary instance and support Enterprise Plus edition.
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+  }
+
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+}
+# [END cloud_sql_mysql_instance_switchover_dr_replica_create]

cloud_sql/mysql_instance_switchover/dr_replica_create/test.yaml

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+# Copyright 2025 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
+# limitations under the License.
+
+apiVersion: blueprints.cloud.google.com/v1alpha1
+kind: BlueprintTest
+metadata:
+  name: mysql_instance_switchover_dr_replica_create
+spec:
+  skip: true

cloud_sql/mysql_instance_switchover/dr_replica_designate/main.tf

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+/**
+ * Copyright 2025 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
+ * limitations under the License.
+ */
+
+# [START cloud_sql_mysql_instance_switchover_dr_replica_designate]
+data "google_project" "default" {
+}
+
+resource "google_sql_database_instance" "original-primary" {
+  name   = "mysql-original-primary-instance"
+  region = "us-east1"
+  # Specify a database version that supports Cloud SQL Enterprise Plus edition.
+  database_version = "MYSQL_8_0"
+  instance_type    = "CLOUD_SQL_INSTANCE"
+
+  replication_cluster {
+    # Designate the DR replica.
+    # The format for setting the DR replica is `project-id:dr-replica-name`.
+    failover_dr_replica_name = "${data.google_project.default.project_id}:mysql-dr-replica-instance"
+  }
+
+  settings {
+    # Specify a tier that supports Cloud SQL Enterprise Plus edition.
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      # You must enable automated backups and binary logging.
+      enabled            = true
+      binary_log_enabled = true
+    }
+  }
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+  # Optional. Add more settings.
+}
+
+resource "google_sql_database_instance" "dr-replica" {
+  name = "mysql-dr-replica-instance"
+  # DR replica must be in a different region than the region of the primary instance.
+  region = "us-west2"
+  # DR replica must be the same database version as the primary instance.
+  database_version = "MYSQL_8_0"
+  instance_type    = "READ_REPLICA_INSTANCE"
+  # Specify the primary instance as the master instance.
+  master_instance_name = google_sql_database_instance.original-primary.name
+
+  settings {
+    # DR replica must be in the same tier as your primary instance and support Enterprise Plus edition.
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+  }
+
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+  # Optional. Add more settings.
+}
+
+# [END cloud_sql_mysql_instance_switchover_dr_replica_designate]

cloud_sql/mysql_instance_switchover/dr_replica_designate/test.yaml

@@ -0,0 +1,20 @@
+# Copyright 2025 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
+# limitations under the License.
+
+apiVersion: blueprints.cloud.google.com/v1alpha1
+kind: BlueprintTest
+metadata:
+  name: mysql_instance_switchover_dr_replica_designate
+spec:
+  skip: true

cloud_sql/mysql_instance_switchover/switchover_begin/main.tf

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+/**
+ * Copyright 2025 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
+ * limitations under the License.
+ */
+
+# [START cloud_sql_mysql_instance_switchover_begin]
+#
+# This sample provides the first part of the switchover operation and turns the DR replica
+# into the new primary instance.
+data "google_project" "default" {
+}
+
+resource "google_sql_database_instance" "original-primary" {
+  name             = "mysql-original-primary-instance"
+  region           = "us-east1"
+  database_version = "MYSQL_8_0"
+  instance_type    = "CLOUD_SQL_INSTANCE"
+
+  replication_cluster {
+    failover_dr_replica_name = "${data.google_project.default.project_id}:mysql-dr-replica-instance"
+  }
+
+  settings {
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      enabled            = true
+      binary_log_enabled = true
+    }
+  }
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+  # Optional. Add more settings.
+}
+
+resource "google_sql_database_instance" "dr-replica" {
+  name             = "mysql-dr-replica-instance"
+  region           = "us-west2"
+  database_version = "MYSQL_8_0"
+  # Change the instance type from "READ_REPLICA_INSTANCE" to "CLOUD_SQL_INSTANCE".
+  instance_type = "CLOUD_SQL_INSTANCE"
+  # Remove or comment out the master_instance_name from the DR replica.
+  # master_instance_name = google_sql_database_instance.original-primary.name
+  # Add the original primary instance to a list of replicas for the new primary.
+  replica_names = [google_sql_database_instance.original-primary.name]
+
+  # Designate the original primary instance as the DR replica of the new primary instance.
+  # The format for setting the DR replica is `project-id:dr-replica-name`.
+  replication_cluster {
+    failover_dr_replica_name = "${data.google_project.default.project_id}:${google_sql_database_instance.original-primary.name}"
+  }
+
+  settings {
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      # Add a backup configuration section to enable automated backups and binary logging for the new primary instance.
+      enabled            = true
+      binary_log_enabled = true
+    }
+  }
+  # Set `deletion_protection` to true to ensure that one can't accidentally
+  # delete this instance by use of Terraform whereas
+  # `deletion_protection_enabled` flag protects this instance at the Google Cloud level.
+  deletion_protection = false
+  # Optional. Add more settings.
+}
+
+# [END cloud_sql_mysql_instance_switchover_begin]

cloud_sql/mysql_instance_switchover/switchover_begin/test.yaml

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+# Copyright 2025 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
+# limitations under the License.
+
+apiVersion: blueprints.cloud.google.com/v1alpha1
+kind: BlueprintTest
+metadata:
+  name: mysql_instance_switchover_switchover_begin
+spec:
+  skip: true

cloud_sql/mysql_instance_switchover/switchover_finish/main.tf

@@ -0,0 +1,85 @@
+/**
+ * Copyright 2025 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
+ * limitations under the License.
+ */
+
+# [START cloud_sql_mysql_instance_switchover_finish]
+#
+# This sample provides the second part of the switchover operation and makes the original primary instance
+# a replica of the new primary instance. After you run `terraform apply` for this sample, you'll see
+# the following message:
+#
+# "No changes. Your infrastructure matches the configuration.
+#
+# Terraform has compared your real infrastructure against your configuration and found no differences,
+# so no changes are needed.
+#
+# Apply complete! Resources: 0 added, 0 changed, 0 destroyed."
+data "google_project" "default" {
+}
+
+resource "google_sql_database_instance" "original-primary" {
+  name             = "mysql-original-primary-instance"
+  region           = "us-east1"
+  database_version = "MYSQL_8_0"
+  # Change instance type for the original primary from "CLOUD_SQL_INSTANCE" to "READ_REPLICA_INSTANCE".
+  instance_type = "READ_REPLICA_INSTANCE"
+  # Set master_instance_name to the the new primary instance, the old DR replica.
+  master_instance_name = "mysql-dr-replica-instance"
+  # replica_names = [] # If you previously defined a replica_names field in your template, then delete the DR replica
+  # (new primary) from the list of replicas.  Don't delete the entire replica_names field.
+  # Instead set the field to an empty string. For example, replica_names = [""].
+
+  replication_cluster {
+    # This instance no longer requires a designated DR replica since it's a replica.
+    # Remove the DR replica designation by setting the field to an empty string.
+    failover_dr_replica_name = ""
+  }
+
+  settings {
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      # Disable automated backups because this instance is now a replica.
+      enabled            = false
+      binary_log_enabled = true
+    }
+  }
+  deletion_protection = false
+}
+
+resource "google_sql_database_instance" "dr-replica" {
+  name             = "mysql-dr-replica-instance"
+  region           = "us-west2"
+  database_version = "MYSQL_8_0"
+  instance_type    = "CLOUD_SQL_INSTANCE"
+  replica_names    = [google_sql_database_instance.original-primary.name]
+
+
+  replication_cluster {
+    failover_dr_replica_name = "${data.google_project.default.project_id}:${google_sql_database_instance.original-primary.name}"
+  }
+
+  settings {
+    tier    = "db-perf-optimized-N-2"
+    edition = "ENTERPRISE_PLUS"
+    backup_configuration {
+      enabled            = true
+      binary_log_enabled = true
+    }
+  }
+  deletion_protection = false
+}
+
+# [END cloud_sql_mysql_instance_switchover_finish]

cloud_sql/mysql_instance_switchover/switchover_finish/test.yaml

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+# Copyright 2025 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
+# limitations under the License.
+
+apiVersion: blueprints.cloud.google.com/v1alpha1
+kind: BlueprintTest
+metadata:
+  name: mysql_instance_switchover_switchover_finish
+spec:
+  skip: true