Read system parameters that exist in config

.changelog/18486.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_docdb_cluster_parameter_group: Read all user parameters and parameters specified in the configuration.
+```

aws/resource_aws_docdb_cluster_parameter_group.go

@@ -155,15 +155,14 @@ func resourceAwsDocDBClusterParameterGroupRead(d *schema.ResourceData, meta inte
 
  describeParametersOpts := &docdb.DescribeDBClusterParametersInput{
  DBClusterParameterGroupName: aws.String(d.Id()),
- Source: aws.String("user"),
  }
 
  describeParametersResp, err := conn.DescribeDBClusterParameters(describeParametersOpts)
  if err != nil {
  return fmt.Errorf("error reading DocDB Cluster Parameter Group (%s) parameters: %s", d.Id(), err)
  }
 
- if err := d.Set("parameter", flattenDocDBParameters(describeParametersResp.Parameters)); err != nil {
+ if err := d.Set("parameter", flattenDocDBParameters(describeParametersResp.Parameters, d.Get("parameter").(*schema.Set).List())); err != nil {
  return fmt.Errorf("error setting docdb cluster parameter: %s", err)
  }
 

aws/resource_aws_docdb_cluster_parameter_group_test.go

@@ -47,6 +47,41 @@ func TestAccAWSDocDBClusterParameterGroup_basic(t *testing.T) {
  })
 }
 
+func TestAccAWSDocDBClusterParameterGroup_systemParameter(t *testing.T) {
+ var v docdb.DBClusterParameterGroup
+ resourceName := "aws_docdb_cluster_parameter_group.bar"
+
+ parameterGroupName := fmt.Sprintf("cluster-parameter-group-test-terraform-%d", acctest.RandInt())
+
+ resource.ParallelTest(t, resource.TestCase{
+ PreCheck: func() { testAccPreCheck(t) },
+ ErrorCheck: testAccErrorCheck(t, docdb.EndpointsID),
+ Providers: testAccProviders,
+ CheckDestroy: testAccCheckAWSDocDBClusterParameterGroupDestroy,
+ Steps: []resource.TestStep{
+ {
+ Config: testAccAWSDocDBClusterParameterGroupConfig_SystemParameter(parameterGroupName),
+ Check: resource.ComposeTestCheckFunc(
+ testAccCheckAWSDocDBClusterParameterGroupExists(resourceName, &v),
+ testAccCheckAWSDocDBClusterParameterGroupAttributes(&v, parameterGroupName),
+ testAccMatchResourceAttrRegionalARN(resourceName, "arn", "rds", regexp.MustCompile(fmt.Sprintf("cluster-pg:%s$", parameterGroupName))),
+ resource.TestCheckResourceAttr(resourceName, "name", parameterGroupName),
+ resource.TestCheckResourceAttr(resourceName, "family", "docdb3.6"),
+ resource.TestCheckResourceAttr(resourceName, "description", "Managed by Terraform"),
+ resource.TestCheckResourceAttr(resourceName, "parameter.#", "1"),
+ resource.TestCheckResourceAttr(resourceName, "tags.%", "0"),
+ ),
+ },
+ {
+ ResourceName: resourceName,
+ ImportState: true,
+ ImportStateVerify: true,
+ ImportStateVerifyIgnore: []string{"parameter"},
+ },
+ },
+ })
+}
+
 func TestAccAWSDocDBClusterParameterGroup_namePrefix(t *testing.T) {
  var v docdb.DBClusterParameterGroup
 
@@ -352,6 +387,21 @@ resource "aws_docdb_cluster_parameter_group" "bar" {
 `, name)
 }
 
+func testAccAWSDocDBClusterParameterGroupConfig_SystemParameter(name string) string {
+ return fmt.Sprintf(`
+resource "aws_docdb_cluster_parameter_group" "bar" {
+ family = "docdb3.6"
+ name = "%s"
+
+ parameter {
+ name = "tls"
+ value = "enabled"
+ apply_method = "pending-reboot"
+ }
+}
+`, name)
+}
+
 func testAccAWSDocDBClusterParameterGroupConfig_Description(name, description string) string {
  return fmt.Sprintf(`
 resource "aws_docdb_cluster_parameter_group" "bar" {

aws/structure.go

@@ -955,10 +955,25 @@ func flattenNeptuneParameters(list []*neptune.Parameter) []map[string]interface{
 }
 
 // Flattens an array of Parameters into a []map[string]interface{}
-func flattenDocDBParameters(list []*docdb.Parameter) []map[string]interface{} {
+func flattenDocDBParameters(list []*docdb.Parameter, parameterList []interface{}) []map[string]interface{} {
  result := make([]map[string]interface{}, 0, len(list))
  for _, i := range list {
  if i.ParameterValue != nil {
+ name := aws.StringValue(i.ParameterName)
+
+ // Check if any non-user parameters are specified in the configuration.
+ parameterFound := false
+ for _, configParameter := range parameterList {
+ if configParameter.(map[string]interface{})["name"] == name {
+ parameterFound = true
+ }
+ }
+
+ // Skip parameters that are not user defined or specified in the configuration.
+ if aws.StringValue(i.Source) != "user" && !parameterFound {
+ continue
+ }
+
  result = append(result, map[string]interface{}{
  "apply_method": aws.StringValue(i.ApplyMethod),
  "name": aws.StringValue(i.ParameterName),

website/docs/r/docdb_cluster_parameter_group.html.markdown

@@ -33,7 +33,7 @@ The following arguments are supported:
 * `name_prefix` - (Optional, Forces new resource) Creates a unique name beginning with the specified prefix. Conflicts with `name`.
 * `family` - (Required, Forces new resource) The family of the documentDB cluster parameter group.
 * `description` - (Optional, Forces new resource) The description of the documentDB cluster parameter group. Defaults to "Managed by Terraform".
-* `parameter` - (Optional) A list of documentDB parameters to apply.
+* `parameter` - (Optional) A list of documentDB parameters to apply. Setting parameters to system default values may show a difference on imported resources.
 * `tags` - (Optional) A map of tags to assign to the resource.
 
 Parameter blocks support the following: