provider/google: use a mutex to prevent concurrent sql instance operations (#14424)

builtin/providers/google/resource_sql_database.go

@@ -57,6 +57,8 @@ func resourceSqlDatabaseCreate(d *schema.ResourceData, meta interface{}) error {
 		Instance: instance_name,
 	}
 
+	mutexKV.Lock(instanceMutexKey(project, instance_name))
+	defer mutexKV.Unlock(instanceMutexKey(project, instance_name))
 	op, err := config.clientSqlAdmin.Databases.Insert(project, instance_name,
 		db).Do()
 
@@ -111,6 +113,8 @@ func resourceSqlDatabaseDelete(d *schema.ResourceData, meta interface{}) error {
 	database_name := d.Get("name").(string)
 	instance_name := d.Get("instance").(string)
 
+	mutexKV.Lock(instanceMutexKey(project, instance_name))
+	defer mutexKV.Unlock(instanceMutexKey(project, instance_name))
 	op, err := config.clientSqlAdmin.Databases.Delete(project, instance_name,
 		database_name).Do()
 

builtin/providers/google/resource_sql_database_instance.go

@@ -1172,3 +1172,7 @@ func validateNumericRange(v interface{}, k string, min int, max int) (ws []strin
 	}
 	return
 }
+
+func instanceMutexKey(project, instance_name string) string {
+	return fmt.Sprintf("google-sql-database-instance-%s-%s", project, instance_name)
+}

builtin/providers/google/resource_sql_database_instance_test.go

@@ -277,6 +277,24 @@ func TestAccGoogleSqlDatabaseInstance_authNets(t *testing.T) {
 	})
 }
 
+// Tests that a SQL instance can be referenced from more than one other resource without
+// throwing an error during provisioning, see #9018.
+func TestAccGoogleSqlDatabaseInstance_multipleOperations(t *testing.T) {
+	databaseID, instanceID, userID := acctest.RandString(8), acctest.RandString(8), acctest.RandString(8)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccGoogleSqlDatabaseInstanceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: fmt.Sprintf(
+					testGoogleSqlDatabaseInstance_multipleOperations, databaseID, instanceID, userID),
+			},
+		},
+	})
+}
+
 func testAccCheckGoogleSqlDatabaseInstanceEquals(n string,
 	instance *sqladmin.DatabaseInstance) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
@@ -678,3 +696,26 @@ resource "google_sql_database_instance" "instance" {
 	}
 }
 `
+
+var testGoogleSqlDatabaseInstance_multipleOperations = `
+resource "google_sql_database_instance" "instance" {
+	name = "tf-test-%s"
+	region = "us-central"
+	settings {
+		tier = "D0"
+		crash_safe_replication = false
+	}
+}
+
+resource "google_sql_database" "database" {
+	name = "tf-test-%s"
+	instance = "${google_sql_database_instance.instance.name}"
+}
+
+resource "google_sql_user" "user" {
+	name = "tf-test-%s"
+	instance = "${google_sql_database_instance.instance.name}"
+	host = "google.com"
+	password = "hunter2"
+}
+`

builtin/providers/google/resource_sql_user.go

@@ -76,6 +76,8 @@ func resourceSqlUserCreate(d *schema.ResourceData, meta interface{}) error {
 		Host:     host,
 	}
 
+	mutexKV.Lock(instanceMutexKey(project, instance))
+	defer mutexKV.Unlock(instanceMutexKey(project, instance))
 	op, err := config.clientSqlAdmin.Users.Insert(project, instance,
 		user).Do()
 
@@ -163,6 +165,8 @@ func resourceSqlUserUpdate(d *schema.ResourceData, meta interface{}) error {
 			Host:     host,
 		}
 
+		mutexKV.Lock(instanceMutexKey(project, instance))
+		defer mutexKV.Unlock(instanceMutexKey(project, instance))
 		op, err := config.clientSqlAdmin.Users.Update(project, instance, host, name,
 			user).Do()
 
@@ -196,6 +200,8 @@ func resourceSqlUserDelete(d *schema.ResourceData, meta interface{}) error {
 	instance := d.Get("instance").(string)
 	host := d.Get("host").(string)
 
+	mutexKV.Lock(instanceMutexKey(project, instance))
+	defer mutexKV.Unlock(instanceMutexKey(project, instance))
 	op, err := config.clientSqlAdmin.Users.Delete(project, instance, host, name).Do()
 
 	if err != nil {