From 563def7d09ede048be9c6b08441616aacc944124 Mon Sep 17 00:00:00 2001
From: Moritz Zimmer <moritzzimmer@users.noreply.github.com>
Date: Thu, 11 Sep 2025 14:42:08 +0200
Subject: [PATCH] feat: event source mapping metrics support

---
 event_source_mappings.tf                            |  8 ++++++++
 .../dynamodb-with-alias/main.tf                     |  6 +++++-
 examples/with-event-source-mappings/kinesis/main.tf |  5 +++++
 examples/with-event-source-mappings/sqs/main.tf     | 13 +++++++++----
 4 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/event_source_mappings.tf b/event_source_mappings.tf
index 41c385e..160821c 100644
--- a/event_source_mappings.tf
+++ b/event_source_mappings.tf
@@ -72,6 +72,14 @@ resource "aws_lambda_event_source_mapping" "event_source" {
     }
   }
 
+  dynamic "metrics_config" {
+    for_each = try([each.value.metrics_config], [])
+
+    content {
+      metrics = metrics_config.value.metrics
+    }
+  }
+
   dynamic "scaling_config" {
     for_each = try(each.value.scaling_config, null) != null ? [true] : []
 
diff --git a/examples/with-event-source-mappings/dynamodb-with-alias/main.tf b/examples/with-event-source-mappings/dynamodb-with-alias/main.tf
index e7469a2..53b8993 100644
--- a/examples/with-event-source-mappings/dynamodb-with-alias/main.tf
+++ b/examples/with-event-source-mappings/dynamodb-with-alias/main.tf
@@ -81,7 +81,6 @@ module "lambda" {
       // see https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventsourcemapping.html
       destination_arn_on_failure = aws_sqs_queue.errors.arn
 
-
       // Lambda event filtering, see https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventfiltering.html
       filter_criteria = [
         {
@@ -99,6 +98,11 @@ module "lambda" {
           })
         }
       ]
+
+      // Event source mapping metrics, see https://docs.aws.amazon.com/lambda/latest/dg/monitoring-metrics-types.html#event-source-mapping-metrics
+      metrics_config = {
+        metrics = ["EventCount"]
+      }
     }
 
     table_2 = {
diff --git a/examples/with-event-source-mappings/kinesis/main.tf b/examples/with-event-source-mappings/kinesis/main.tf
index b2d4aba..2451ab6 100644
--- a/examples/with-event-source-mappings/kinesis/main.tf
+++ b/examples/with-event-source-mappings/kinesis/main.tf
@@ -65,6 +65,11 @@ module "lambda" {
           })
         }
       ]
+
+      // Event source mapping metrics, see https://docs.aws.amazon.com/lambda/latest/dg/monitoring-metrics-types.html#event-source-mapping-metrics
+      metrics_config = {
+        metrics = ["EventCount"]
+      }
     }
 
     stream_2 = {
diff --git a/examples/with-event-source-mappings/sqs/main.tf b/examples/with-event-source-mappings/sqs/main.tf
index 23cef98..39dc8f6 100644
--- a/examples/with-event-source-mappings/sqs/main.tf
+++ b/examples/with-event-source-mappings/sqs/main.tf
@@ -45,10 +45,6 @@ module "lambda" {
       // optionally overwrite arguments from https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/lambda_event_source_mapping
       batch_size = 5
 
-      scaling_config = {
-        maximum_concurrency = 2
-      }
-
       // Lambda event filtering, see https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventfiltering.html
       filter_criteria = [
         {
@@ -66,6 +62,15 @@ module "lambda" {
           })
         }
       ]
+
+      // Event source mapping metrics, see https://docs.aws.amazon.com/lambda/latest/dg/monitoring-metrics-types.html#event-source-mapping-metrics
+      metrics_config = {
+        metrics = ["EventCount"]
+      }
+
+      scaling_config = {
+        maximum_concurrency = 2
+      }
     }
 
     queue_2 = {