feat: Add lambda dead-letter queue variables (#180)

Co-authored-by: chris3ware <36608309+chris3ware@users.noreply.github.com>

Author: antonbabenko

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/antonbabenko/pre-commit-terraform
-    rev: v1.62.3
+    rev: v1.76.0
     hooks:
       - id: terraform_fmt
       - id: terraform_validate
@@ -23,7 +23,7 @@ repos:
           - '--args=--only=terraform_standard_module_structure'
           - '--args=--only=terraform_workspace_remote'
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.1.0
+    rev: v4.3.0
     hooks:
       - id: check-merge-conflict
       - id: end-of-file-fixer

README.md

@@ -106,6 +106,8 @@ See the [functions](https://github.com/terraform-aws-modules/terraform-aws-notif
 | <a name="input_iam_role_path"></a> [iam\_role\_path](#input\_iam\_role\_path) | Path of IAM role to use for Lambda Function | `string` | `null` | no |
 | <a name="input_iam_role_tags"></a> [iam\_role\_tags](#input\_iam\_role\_tags) | Additional tags for the IAM role | `map(string)` | `{}` | no |
 | <a name="input_kms_key_arn"></a> [kms\_key\_arn](#input\_kms\_key\_arn) | ARN of the KMS key used for decrypting slack webhook url | `string` | `""` | no |
+| <a name="input_lambda_attach_dead_letter_policy"></a> [lambda\_attach\_dead\_letter\_policy](#input\_lambda\_attach\_dead\_letter\_policy) | Controls whether SNS/SQS dead letter notification policy should be added to IAM role for Lambda Function | `bool` | `false` | no |
+| <a name="input_lambda_dead_letter_target_arn"></a> [lambda\_dead\_letter\_target\_arn](#input\_lambda\_dead\_letter\_target\_arn) | The ARN of an SNS topic or SQS queue to notify when an invocation fails. | `string` | `null` | no |
 | <a name="input_lambda_description"></a> [lambda\_description](#input\_lambda\_description) | The description of the Lambda function | `string` | `null` | no |
 | <a name="input_lambda_function_ephemeral_storage_size"></a> [lambda\_function\_ephemeral\_storage\_size](#input\_lambda\_function\_ephemeral\_storage\_size) | Amount of ephemeral storage (/tmp) in MB your Lambda Function can use at runtime. Valid value between 512 MB to 10,240 MB (10 GB). | `number` | `512` | no |
 | <a name="input_lambda_function_name"></a> [lambda\_function\_name](#input\_lambda\_function\_name) | The name of the Lambda function to create | `string` | `"notify_slack"` | no |

main.tf

@@ -118,6 +118,9 @@ module "lambda" {
   use_existing_cloudwatch_log_group = true
   attach_network_policy             = var.lambda_function_vpc_subnet_ids != null
 
+  dead_letter_target_arn    = var.lambda_dead_letter_target_arn
+  attach_dead_letter_policy = var.lambda_attach_dead_letter_policy
+
   allowed_triggers = {
     AllowExecutionFromSNS = {
       principal  = "sns.amazonaws.com"

variables.tf

@@ -34,6 +34,18 @@ variable "lambda_source_path" {
   default     = null
 }
 
+variable "lambda_dead_letter_target_arn" {
+  description = "The ARN of an SNS topic or SQS queue to notify when an invocation fails."
+  type        = string
+  default     = null
+}
+
+variable "lambda_attach_dead_letter_policy" {
+  description = "Controls whether SNS/SQS dead letter notification policy should be added to IAM role for Lambda Function"
+  type        = bool
+  default     = false
+}
+
 variable "sns_topic_name" {
   description = "The name of the SNS topic to create"
   type        = string