Docs, Version

Author: kyleaa

CHANGELOG.md

@@ -1,3 +1,6 @@
+v0.8.0
+- Enhancement: Support IMDSv2 (Requires ExAws 2.3.2 minimum) https://github.com/kyleaa/libcluster_ec2/pull/33
+
 v0.7.0
 - Enhancement: auto reconnect when disconnected by some reason https://github.com/kyleaa/libcluster_ec2/pull/27
 - Dependency Cleanup: Remove Poison dependency https://github.com/kyleaa/libcluster_ec2/pull/23

README.md

@@ -27,3 +27,26 @@ def deps do
   [{:libcluster_ec2, "~> 0.5"}]
 end
 ```
+
+## AWS IAM Requirements
+
+Instances must have an instance role attached. There are two permissions required:
+* `ec2:DescribeInstances` - Required to determine tag values of the current running instance. Can be restricted by Resource to the current instance running the application
+* `ec2:DescribeTags` - Required to identify other instances with the same tags 
+
+```
+{
+    "Version": "2012-10-17",
+    "Statement": [
+        {
+            "Sid": "VisualEditor0",
+            "Effect": "Allow",
+            "Action": [
+                "ec2:DescribeInstances",
+                "ec2:DescribeTags"
+            ],
+            "Resource": "*"
+        }
+    ]
+}
+```

lib/libcluster_ec2.ex

@@ -17,7 +17,7 @@ defmodule ClusterEC2 do
     |> String.slice(0..-2//1)
   end
 
-  def get_metadata(path) do
+  defp get_metadata(path) do
     ExAws.Config.new(:ec2)
     |> ExAws.InstanceMeta.request("http://169.254.169.254/latest/meta-data#{path}")
   end