From 27b20d17aed586d7ee0f7ae1c1c15667e1b7f467 Mon Sep 17 00:00:00 2001
From: Joshua Powers <powersj@fastmail.com>
Date: Mon, 30 Oct 2023 02:15:47 -0600
Subject: [PATCH] fix(inputs.ecs): Test for v4 metadata endpoint (#14194)

---
 plugins/inputs/ecs/ecs.go      |  9 +++++++++
 plugins/inputs/ecs/ecs_test.go | 13 +++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/plugins/inputs/ecs/ecs.go b/plugins/inputs/ecs/ecs.go
index 212f408f9..216060de7 100644
--- a/plugins/inputs/ecs/ecs.go
+++ b/plugins/inputs/ecs/ecs.go
@@ -122,6 +122,15 @@ func resolveEndpoint(ecs *Ecs) {
 
 	// Auto-detect metadata endpoint version.
 
+	// Use metadata v4 if available.
+	// https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-metadata-endpoint-v4.html
+	v4Endpoint := os.Getenv("ECS_CONTAINER_METADATA_URI_V4")
+	if v4Endpoint != "" {
+		ecs.EndpointURL = v4Endpoint
+		ecs.metadataVersion = 4
+		return
+	}
+
 	// Use metadata v3 if available.
 	// https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-metadata-endpoint-v3.html
 	v3Endpoint := os.Getenv("ECS_CONTAINER_METADATA_URI")
diff --git a/plugins/inputs/ecs/ecs_test.go b/plugins/inputs/ecs/ecs_test.go
index 078f807c6..356abcaa8 100644
--- a/plugins/inputs/ecs/ecs_test.go
+++ b/plugins/inputs/ecs/ecs_test.go
@@ -808,6 +808,19 @@ func TestResolveEndpoint(t *testing.T) {
 				metadataVersion: 3,
 			},
 		},
+		{
+			name: "Endpoint is not set, ECS_CONTAINER_METADATA_URI_V4 is set => use v4 metadata",
+			setEnv: func(t *testing.T) {
+				t.Setenv("ECS_CONTAINER_METADATA_URI_V4", "v4-endpoint.local")
+			},
+			given: Ecs{
+				EndpointURL: "",
+			},
+			exp: Ecs{
+				EndpointURL:     "v4-endpoint.local",
+				metadataVersion: 4,
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {