providers/aws: fix/improve RDS pointers handling

* d.Set has a pointer nil check we can lean on
* need to be a bit more conservative about nil checks on nested structs;
  (this fixes the RDS acceptance tests)

/cc @fanhaf

builtin/providers/aws/resource_aws_db_instance.go

@@ -304,33 +304,38 @@ func resourceAwsDbInstanceRead(d *schema.ResourceData, meta interface{}) error {
 		return nil
 	}
 
-	if v.DBName != nil {
-		d.Set("name", *v.DBName)
-	} else {
-		d.Set("name", "")
+	d.Set("name", v.DBName)
+	d.Set("username", v.MasterUsername)
+	d.Set("engine", v.Engine)
+	d.Set("engine_version", v.EngineVersion)
+	d.Set("allocated_storage", v.AllocatedStorage)
+	d.Set("storage_type", v.StorageType)
+	d.Set("instance_class", v.DBInstanceClass)
+	d.Set("availability_zone", v.AvailabilityZone)
+	d.Set("backup_retention_period", v.BackupRetentionPeriod)
+	d.Set("backup_window", v.PreferredBackupWindow)
+	d.Set("maintenance_window", v.PreferredMaintenanceWindow)
+	d.Set("multi_az", v.MultiAZ)
+	if v.DBSubnetGroup != nil {
+		d.Set("db_subnet_group_name", v.DBSubnetGroup.DBSubnetGroupName)
 	}
-	d.Set("username", *v.MasterUsername)
-	d.Set("engine", *v.Engine)
-	d.Set("engine_version", *v.EngineVersion)
-	d.Set("allocated_storage", *v.AllocatedStorage)
-	d.Set("storage_type", *v.StorageType)
-	d.Set("instance_class", *v.DBInstanceClass)
-	d.Set("availability_zone", *v.AvailabilityZone)
-	d.Set("backup_retention_period", *v.BackupRetentionPeriod)
-	d.Set("backup_window", *v.PreferredBackupWindow)
-	d.Set("maintenance_window", *v.PreferredMaintenanceWindow)
-	d.Set("multi_az", *v.MultiAZ)
-	d.Set("port", *v.Endpoint.Port)
-	d.Set("db_subnet_group_name", *v.DBSubnetGroup.DBSubnetGroupName)
 
 	if len(v.DBParameterGroups) > 0 {
-		d.Set("parameter_group_name", *v.DBParameterGroups[0].DBParameterGroupName)
+		d.Set("parameter_group_name", v.DBParameterGroups[0].DBParameterGroupName)
 	}
 
-	d.Set("address", *v.Endpoint.Address)
-	d.Set("endpoint", fmt.Sprintf("%s:%d", *v.Endpoint.Address, *v.Endpoint.Port))
-	d.Set("status", *v.DBInstanceStatus)
-	d.Set("storage_encrypted", *v.StorageEncrypted)
+	if v.Endpoint != nil {
+		d.Set("port", v.Endpoint.Port)
+		d.Set("address", v.Endpoint.Address)
+
+		if v.Endpoint.Address != nil && v.Endpoint.Port != nil {
+			d.Set("endpoint",
+				fmt.Sprintf("%s:%d", *v.Endpoint.Address, *v.Endpoint.Port))
+		}
+	}
+
+	d.Set("status", v.DBInstanceStatus)
+	d.Set("storage_encrypted", v.StorageEncrypted)
 
 	// Create an empty schema.Set to hold all vpc security group ids
 	ids := &schema.Set{

builtin/providers/aws/resource_aws_db_instance_test.go

@@ -2,7 +2,9 @@ package aws
 
 import (
 	"fmt"
+	"math/rand"
 	"testing"
+	"time"
 
 	"github.com/hashicorp/terraform/helper/resource"
 	"github.com/hashicorp/terraform/terraform"
@@ -24,8 +26,6 @@ func TestAccAWSDBInstance(t *testing.T) {
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckAWSDBInstanceExists("aws_db_instance.bar", &v),
 					testAccCheckAWSDBInstanceAttributes(&v),
-					resource.TestCheckResourceAttr(
-						"aws_db_instance.bar", "identifier", "foobarbaz-test-terraform"),
 					resource.TestCheckResourceAttr(
 						"aws_db_instance.bar", "allocated_storage", "10"),
 					resource.TestCheckResourceAttr(
@@ -133,9 +133,12 @@ func testAccCheckAWSDBInstanceExists(n string, v *rds.DBInstance) resource.TestC
 	}
 }
 
-const testAccAWSDBInstanceConfig = `
+// Database names cannot collide, and deletion takes so long, that making the
+// name a bit random helps so able we can kill a test that's just waiting for a
+// delete and not be blocked on kicking off another one.
+var testAccAWSDBInstanceConfig = fmt.Sprintf(`
 resource "aws_db_instance" "bar" {
-	identifier = "foobarbaz-test-terraform"
+	identifier = "foobarbaz-test-terraform-%d"
 
 	allocated_storage = 10
 	engine = "mysql"
@@ -148,5 +151,4 @@ resource "aws_db_instance" "bar" {
 	backup_retention_period = 0
 
 	parameter_group_name = "default.mysql5.6"
-}
-`
+}`, rand.New(rand.NewSource(time.Now().UnixNano())).Int())