Using Terraform to dump/restore a MariaDB database - mysql

Question

No cloud resources are in use here.
I am new to using Terraform.
I am using Terraform 0.12 to install software on a server. That software expects the remote MariaDB database to be empty, which is done manually. (The software will cause Terraform to abort if the database is not empty.) Right now it is all dummy data.
I would like use Terraform to mysqldump the database prior to destroying the database so that same dump can be restored on a terraform apply. Eventually, the contents of the database need to be preserved between software upgrades.
I have Terraform code to create and destroy the server and install the software. That works fine. The database is handled manually at the moment. When uncommented, the Terraform code to connect to the database works, but I do not have enough experience to do anything more beyond that.
provider "mysql" {
endpoint = "10.0.1.2"
username = "terraform"
password = "changeme"
version = "~> 1.6"
}
resource "mysql_database" "default" {
default_character_set = "utf8"
name = "terraform_test_db"
}

Answer 1

You can use destroy time provisioners to trigger an provisioner action to happen before Terraform tries to destroy the resource.
provider "mysql" {
endpoint = "10.0.1.2"
username = "terraform"
password = "changeme"
version = "~> 1.6"
}
resource "mysql_database" "default" {
name = "terraform_test_db"
default_character_set = "utf8"
provisioner "local-exec" {
when = "destroy"
command = "mysqldump [options] > dump.sql"
}
}