resource/aws_ecs_task_definition - prevent panic on null container definition

.changelog/27263.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_ecs_task_definition: Prevent panic when supplying a `null` value in `container_definitions`
+```

internal/service/ecs/task_definition.go

@@ -1208,6 +1208,12 @@ func expandContainerDefinitions(rawDefinitions string) ([]*ecs.ContainerDefiniti
 		return nil, fmt.Errorf("Error decoding JSON: %s", err)
 	}
 
+	for i, c := range definitions {
+		if c == nil {
+			return nil, fmt.Errorf("invalid container definition supplied at index (%d)", i)
+		}
+	}
+
 	return definitions, nil
 }
 

internal/service/ecs/task_definition_test.go

@@ -1002,6 +1002,23 @@ func TestAccECSTaskDefinition_inferenceAccelerator(t *testing.T) {
 	})
 }
 
+func TestAccECSTaskDefinition_invalidContainerDefinition(t *testing.T) {
+	rName := sdkacctest.RandomWithPrefix(acctest.ResourcePrefix)
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:                 func() { acctest.PreCheck(t) },
+		ErrorCheck:               acctest.ErrorCheck(t, ecs.EndpointsID),
+		ProtoV5ProviderFactories: acctest.ProtoV5ProviderFactories,
+		CheckDestroy:             testAccCheckTaskDefinitionDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config:      testAccTaskDefinitionConfig_invalidContainerDefinition(rName),
+				ExpectError: regexp.MustCompile(`invalid container definition supplied at index \(1\)`),
+			},
+		},
+	})
+}
+
 func testAccTaskDefinitionConfig_proxyConfiguration(rName string, containerName string, proxyType string,
 	ignoredUid string, ignoredGid string, appPorts string, proxyIngressPort string, proxyEgressPort string,
 	egressIgnoredPorts string, egressIgnoredIPs string) string {
@@ -2616,3 +2633,32 @@ resource "aws_fsx_windows_file_system" "test" {
 }
 `)
 }
+
+func testAccTaskDefinitionConfig_invalidContainerDefinition(rName string) string {
+	return fmt.Sprintf(`
+resource "aws_ecs_task_definition" "test" {
+  family = %[1]q
+
+  container_definitions = <<TASK_DEFINITION
+[
+	{
+		"cpu": 10,
+		"command": ["sleep", "10"],
+		"entryPoint": ["/"],
+		"essential": true,
+		"image": "mongodb",
+		"memory": 128,
+		"name": "mongodb",
+		"portMappings": [
+			{
+				"containerPort": 28017,
+				"hostPort": 28017
+			}
+		]
+	},
+	null
+]
+TASK_DEFINITION
+}
+`, rName)
+}