Add note about getting credentials for an assumed role

notes/aws/assume-role-credentials.md

@@ -0,0 +1,32 @@
+---
+title: Get credentials for an assumed role
+tags:
+  - AWS
+link: https://aws.amazon.com/premiumsupport/knowledge-center/iam-assume-role-cli/
+emoji: 🔑
+---
+
+It's often useful to get regular access keys as if you were assumed into another role. This is possible:
+
+```
+aws sts assume-role --role-arn arn:aws:iam::<account>:role/<role> --role-session-name <name>
+```
+
+This produces JSON output (it's the most readable of the 3 `aws` supports):
+
+```json
+{
+    "Credentials": {
+        "AccessKeyId": "xxxxxxxxxxxxxxx",
+        "SecretAccessKey": "xxxxxxxxxxxxxxxxxxxxxxxxxx",
+        "SessionToken": "xxxxxxxxxxxxxxxxxxxxxxxxxx",
+        "Expiration": "2022-09-13T17:18:44Z"
+    },
+    "AssumedRoleUser": {
+        "AssumedRoleId": "xxxxxxxxxxxxxxxx:<name>",
+        "Arn": "arn:aws:sts::<account>:assumed-role/<role>/<name>"
+    }
+}
+```
+
+See also the [`assume-role`](https://docs.aws.amazon.com/cli/latest/reference/sts/assume-role.html) command's docs