RDS: Added two CW log export values to support postgresql

[tylersmith34]

This change allows for CloudWatch log exports to be enabled for PostgreSQL databases v9.6.6 and newer. Older versions use the existing log exports but newer versions have their own list. This PR adds those new values to the list and to the documentation.

Changes proposed in this pull request:

• Update the list in the aws_db_instance code
• Update the list in the documentation

Note, it's in two commits because my company blocks access to GitHub so I had to use the GUI to make the changes.

Output from acceptance testing:

$ make testacc TESTARGS='-run=TestAccAWSAvailabilityZones'

...

I didn't run the acceptance tests, I don't have an account where I can incur charges and I only added two items to a list.

[tylersmith34]

Supporting documentation:
https://aws.amazon.com/about-aws/whats-new/2018/12/amazon-rds-supports-postgresql-logfiles-publish-to-amazon-cloudwatch-logs/
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_LogAccess.Concepts.PostgreSQL.html#USER_LogAccess.PostgreSQL.PublishtoCloudWatchLogs

[bflad]

LGTM, thanks @tylersmith34! 🚀

I'm adding an acceptance test on merge just to prevent future regressions. 👍

--- PASS: TestAccAWSDBInstance_EnabledCloudwatchLogsExports_Postgresql (599.82s)

func TestAccAWSDBInstance_EnabledCloudwatchLogsExports_Postgresql(t *testing.T) {
	var dbInstance rds.DBInstance

	rName := acctest.RandomWithPrefix("tf-acc-test")
	resourceName := "aws_db_instance.test"

	resource.ParallelTest(t, resource.TestCase{
		PreCheck:     func() { testAccPreCheck(t) },
		Providers:    testAccProviders,
		CheckDestroy: testAccCheckAWSDBInstanceDestroy,
		Steps: []resource.TestStep{
			{
				Config: testAccAWSDBInstanceConfig_EnabledCloudwatchLogsExports_Postgresql(rName),
				Check: resource.ComposeTestCheckFunc(
					testAccCheckAWSDBInstanceExists(resourceName, &dbInstance),
					resource.TestCheckResourceAttr(resourceName, "enabled_cloudwatch_logs_exports.#", "2"),
				),
			},
			{
				ResourceName:            resourceName,
				ImportState:             true,
				ImportStateVerify:       true,
				ImportStateVerifyIgnore: []string{"password"},
			},
		},
	})
}

func testAccAWSDBInstanceConfig_EnabledCloudwatchLogsExports_Postgresql(rName string) string {
	return fmt.Sprintf(`
resource "aws_db_instance" "test" {
  allocated_storage               = 10
  enabled_cloudwatch_logs_exports = ["postgresql", "upgrade"]
  engine                          = "postgres"
  identifier                      = %q
  instance_class                  = "db.t2.micro"
  password                        = "avoid-plaintext-passwords"
  username                        = "tfacctest"
  skip_final_snapshot             = true
}
`, rName)
}

[tylersmith34]

@bflad Do you want me to add that acceptance test and submit a PR?

[bflad]

I already added it.

[bflad]

This has been released in version 1.52.0 of the AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

[guersam]

I guess these should be allowed in aws_rds_cluster resource too. WDYT?

UPDATE
Nevermind, aurora-postgresql engine does not support exporting to CloudWatch Logs yet.

[ckuehl]

Nevermind, aurora-postgresql engine does not support exporting to CloudWatch Logs yet.

It appears that it does now, so similar changes need to be made to aws_rds_cluster.

Specifically, just postgresql appears to be supported:

        {
            "Engine": "aurora-postgresql",
            "EngineVersion": "10.7",
            "DBParameterGroupFamily": "aurora-postgresql10",
            "DBEngineDescription": "Aurora (PostgreSQL)",
            "DBEngineVersionDescription": "Aurora PostgreSQL (compatible with PostgreSQL 10.7)",
            "ValidUpgradeTarget": [],
            "ExportableLogTypes": [
                "postgresql"
            ],
            "SupportsLogExportsToCloudwatchLogs": true,
            "SupportsReadReplica": false,
            "SupportedEngineModes": [
                "provisioned"
            ],
            "SupportedFeatureNames": [
                "s3Import"
            ]
        }

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!