d/aws_db_instance: Add max_allocated_storage attribute

.changelog/32477.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+data-source/aws_db_instance: Add `max_allocated_storage` attribute
+```

internal/service/rds/instance_data_source.go

@@ -138,6 +138,10 @@ func DataSourceInstance() *schema.Resource {
 					},
 				},
 			},
+			"max_allocated_storage": {
+				Type:     schema.TypeInt,
+				Computed: true,
+			},
 			"monitoring_interval": {
 				Type:     schema.TypeInt,
 				Computed: true,
@@ -252,6 +256,7 @@ func dataSourceInstanceRead(ctx context.Context, d *schema.ResourceData, meta in
 			return sdkdiag.AppendErrorf(diags, "setting master_user_secret: %s", err)
 		}
 	}
+	d.Set("max_allocated_storage", v.MaxAllocatedStorage)
 	d.Set("monitoring_interval", v.MonitoringInterval)
 	d.Set("monitoring_role_arn", v.MonitoringRoleArn)
 	d.Set("multi_az", v.MultiAZ)

internal/service/rds/instance_data_source_test.go

@@ -44,6 +44,7 @@ func TestAccRDSInstanceDataSource_basic(t *testing.T) {
 					resource.TestCheckResourceAttrPair(dataSourceName, "hosted_zone_id", resourceName, "hosted_zone_id"),
 					resource.TestCheckResourceAttrPair(dataSourceName, "iops", resourceName, "iops"),
 					resource.TestCheckResourceAttrPair(dataSourceName, "master_username", resourceName, "username"),
+					resource.TestCheckResourceAttrPair(dataSourceName, "max_allocated_storage", resourceName, "max_allocated_storage"),
 					resource.TestCheckResourceAttrPair(dataSourceName, "multi_az", resourceName, "multi_az"),
 					resource.TestCheckResourceAttrPair(dataSourceName, "network_type", resourceName, "network_type"),
 					resource.TestCheckResourceAttrPair(dataSourceName, "port", resourceName, "port"),
@@ -120,6 +121,7 @@ resource "aws_db_instance" "test" {
   password                = "avoid-plaintext-passwords"
   skip_final_snapshot     = true
   username                = "tfacctest"
+  max_allocated_storage   = 100
 
   enabled_cloudwatch_logs_exports = [
     "audit",

website/docs/d/db_instance.html.markdown

@@ -52,6 +52,7 @@ In addition to all arguments above, the following attributes are exported:
 * `license_model` - License model information for this DB instance.
 * `master_username` - Contains the master username for the DB instance.
 * `master_user_secret` - Provides the master user secret. Only available when `manage_master_user_password` is set to true. [Documented below](#master_user_secret).
+* `max_allocated_storage` - The upper limit to which Amazon RDS can automatically scale the storage of the DB instance.
 * `monitoring_interval` - Interval, in seconds, between points when Enhanced Monitoring metrics are collected for the DB instance.
 * `monitoring_role_arn` - ARN for the IAM role that permits RDS to send Enhanced Monitoring metrics to CloudWatch Logs.
 * `multi_az` - If the DB instance is a Multi-AZ deployment.