feat: dlm: Add support for target_region parameter in cross_region_co…

…py_rule

`target_region` should only be used for dlm policies of
`policy_type=IMAGE_MANAGEMENT`. Creating `IMAGE_MANAGEMENT` policies
using `target` raises a validation error from the AWS API.

Previously the argument was marked as deprecated from the AWS docs, but
after contacting the AWS support, the documentation was updated to
specify that `TargetRegion` should be used only for `IMAGE_MANAGEMENT`
policies, while `Target` only for `EBS_SNAPSHOT_MANAGEMENT` policies.

See the relevant docs: https://docs.aws.amazon.com/dlm/latest/APIReference/API_CrossRegionCopyRule.html

Relevant issues:

- https://discuss.hashicorp.com/t/fail-to-create-a-cross-region-copy-rule-for-dlp/46076
- hashicorp#24226

This fixes hashicorp#24226

.changelog/33796.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/aws_dlm_lifecycle_policy: Add `target_region` argument in `cross_region_copy_rule`, to be used for `IMAGE_MANAGEMENT` policies.
+```

internal/service/dlm/lifecycle_policy.go

@@ -335,7 +335,12 @@ func ResourceLifecyclePolicy() *schema.Resource {
 												},
 												"target": {
 													Type:         schema.TypeString,
-													Required:     true,
+													Optional:     true,
+													ValidateFunc: validation.StringMatch(regexache.MustCompile(`^[\w:\-\/\*]+$`), ""),
+												},
+												"target_region": {
+													Type:         schema.TypeString,
+													Optional:     true,
 													ValidateFunc: validation.StringMatch(regexache.MustCompile(`^[\w:\-\/\*]+$`), ""),
 												},
 											},
@@ -944,6 +949,9 @@ func expandCrossRegionCopyRules(l []interface{}) []*dlm.CrossRegionCopyRule {
 		if v, ok := m["target"].(string); ok && v != "" {
 			rule.Target = aws.String(v)
 		}
+		if v, ok := m["target_region"].(string); ok && v != "" {
+			rule.TargetRegion = aws.String(v)
+		}
 
 		rules = append(rules, rule)
 	}
@@ -970,6 +978,7 @@ func flattenCrossRegionCopyRules(rules []*dlm.CrossRegionCopyRule) []interface{}
 			"encrypted":      aws.BoolValue(rule.Encrypted),
 			"retain_rule":    flattenCrossRegionCopyRuleRetainRule(rule.RetainRule),
 			"target":         aws.StringValue(rule.Target),
+			"target_region":  aws.StringValue(rule.TargetRegion),
 		}
 
 		result = append(result, m)

internal/service/dlm/lifecycle_policy_test.go

@@ -454,6 +454,42 @@ func TestAccDLMLifecyclePolicy_crossRegionCopyRule(t *testing.T) {
 	})
 }
 
+func TestAccDLMLifecyclePolicy_crossRegionCopyRuleImageManagement(t *testing.T) {
+	ctx := acctest.Context(t)
+	rName := sdkacctest.RandomWithPrefix(acctest.ResourcePrefix)
+	resourceName := "aws_dlm_lifecycle_policy.test"
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck: func() {
+			acctest.PreCheck(ctx, t)
+			acctest.PreCheckMultipleRegion(t, 2)
+			testAccPreCheck(ctx, t)
+		},
+		ErrorCheck:               acctest.ErrorCheck(t, dlm.EndpointsID),
+		ProtoV5ProviderFactories: acctest.ProtoV5FactoriesAlternate(ctx, t),
+		CheckDestroy:             testAccCheckLifecyclePolicyDestroy(ctx),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccLifecyclePolicyConfig_crossRegionCopyRuleImageManagement(rName),
+				Check: resource.ComposeTestCheckFunc(
+					checkLifecyclePolicyExists(ctx, resourceName),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.policy_type", "IMAGE_MANAGEMENT"),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.schedule.0.cross_region_copy_rule.#", "1"),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.schedule.0.cross_region_copy_rule.0.encrypted", "false"),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.schedule.0.cross_region_copy_rule.0.retain_rule.0.interval", "15"),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.schedule.0.cross_region_copy_rule.0.retain_rule.0.interval_unit", "DAYS"),
+					resource.TestCheckResourceAttr(resourceName, "policy_details.0.schedule.0.cross_region_copy_rule.0.target_region", acctest.AlternateRegion()),
+				),
+			},
+			{
+				ResourceName:      resourceName,
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
+		},
+	})
+}
+
 func TestAccDLMLifecyclePolicy_tags(t *testing.T) {
 	ctx := acctest.Context(t)
 	rName := sdkacctest.RandomWithPrefix(acctest.ResourcePrefix)
@@ -1077,6 +1113,47 @@ resource "aws_dlm_lifecycle_policy" "test" {
 `, rName, acctest.AlternateRegion()))
 }
 
+func testAccLifecyclePolicyConfig_crossRegionCopyRuleImageManagement(rName string) string {
+	return acctest.ConfigCompose(
+		lifecyclePolicyBaseConfig(rName),
+		fmt.Sprintf(`
+resource "aws_dlm_lifecycle_policy" "test" {
+  description        = %[1]q
+  execution_role_arn = aws_iam_role.test.arn
+
+  policy_details {
+	policy_type = "IMAGE_MANAGEMENT"
+    resource_types = ["INSTANCE"]
+
+    schedule {
+      name = %[1]q
+
+      create_rule {
+        interval = 12
+      }
+
+      retain_rule {
+        count = 10
+      }
+
+      cross_region_copy_rule {
+        target_region    = %[2]q
+        encrypted 		 = false
+        retain_rule {
+          interval      = 15
+          interval_unit = "DAYS"
+        }
+      }
+    }
+
+    target_tags = {
+      Name = %[1]q
+    }
+  }
+}
+`, rName, acctest.AlternateRegion()))
+}
+
 func testAccLifecyclePolicyConfig_updateCrossRegionCopyRule(rName string) string {
 	return acctest.ConfigCompose(
 		acctest.ConfigMultipleRegionProvider(2),

website/docs/r/dlm_lifecycle_policy.html.markdown

@@ -324,7 +324,8 @@ This resource supports the following arguments:
 * `deprecate_rule` - (Optional) The AMI deprecation rule for cross-Region AMI copies created by the rule. See the [`deprecate_rule`](#cross-region-copy-rule-deprecate-rule-arguments) block.
 * `encrypted` - (Required) To encrypt a copy of an unencrypted snapshot if encryption by default is not enabled, enable encryption using this parameter. Copies of encrypted snapshots are encrypted, even if this parameter is false or if encryption by default is not enabled.
 * `retain_rule` - (Required) The retention rule that indicates how long snapshot copies are to be retained in the destination Region. See the [`retain_rule`](#cross-region-copy-rule-retain-rule-arguments) block. Max of 1 per schedule.
-* `target` - (Required) The target Region or the Amazon Resource Name (ARN) of the target Outpost for the snapshot copies.
+* `target` - Use only for DLM policies of `policy_type=EBS_SNAPSHOT_MANAGEMENT`. The target Region or the Amazon Resource Name (ARN) of the target Outpost for the snapshot copies.
+* `target_region` - Use only for DLM policies of `policy_type=IMAGE_MANAGEMENT`. The target Region or the Amazon Resource Name (ARN) of the target Outpost for the snapshot copies.
 
 #### Cross Region Copy Rule Deprecate Rule arguments