meta: Improve aws-node example readme

examples/aws-nodejs/README.md

@@ -8,42 +8,86 @@ Express.js). It uses presigned URL at the backend level.
 It's assumed that you are familiar with AWS, at least, with the storage service
 (S3) and users & policies (IAM).
 
-These instructions are **not fit for production** but tightening the security is
+These instructions are **not fit for production**, tightening the security is
 out of the scope here.
 
 ### S3 Setup
 
-- Create new S3 bucket in AWS (e.g. `aws-nodejs`).
-- Add a bucket policy.
-
-  ```json
-  {
-    "Version": "2012-10-17",
-    "Statement": [
-      {
-        "Sid": "PublicAccess",
-        "Effect": "Allow",
-        "Principal": "*",
-        "Action": "s3:GetObject",
-        "Resource": "arn:aws:s3:::aws-nodejs/*"
-      }
+Assuming you’re trying to setup the user `MY-UPPY-USER` to put the uploaded
+files to the bucket `MY-UPPY-BUCKET`, here’s how you can allow `MY-UPPY-USER` to
+get STS Federated Token and upload files to `MY-UPPY-BUCKET`:
+
+1. Set CORS settings on `MY-UPPY-BUCKET` bucket:
+
+    ```json
+    [
+        {
+            "AllowedHeaders": [
+                "*"
+            ],
+            "AllowedMethods": [
+                "GET",
+                "PUT",
+                "HEAD",
+                "POST",
+                "DELETE"
+            ],
+            "AllowedOrigins": [
+                "*"
+            ],
+            "ExposeHeaders": [
+                "ETag",
+                "Location"
+            ]
+        }
     ]
-  }
-  ```
+    ```
 
-- Make the S3 bucket public.
-- Add CORS configuration.
+2. Add the following Policy to `MY-UPPY-BUCKET`:
 
-  ```json
-  [
+    ```json
     {
-      "AllowedHeaders": ["*"],
-      "AllowedMethods": ["GET", "PUT", "HEAD", "POST", "DELETE"],
-      "AllowedOrigins": ["*"],
-      "ExposeHeaders": []
+        "Version": "2012-10-17",
+        "Statement": [
+            {
+                "Sid": "MyMultipartPolicyStatement1",
+                "Effect": "Allow",
+                "Principal": {
+                    "AWS": "arn:aws:iam::*:user/MY-UPPY-USER"
+                },
+                "Action": [
+                    "s3:PutObject",
+                    "s3:PutObjectAcl",
+                    "s3:ListMultipartUploadParts",
+                    "s3:AbortMultipartUpload"
+                ],
+                "Resource": "arn:aws:s3:::MY-UPPY-BUCKET/*"
+            }
+        ]
     }
-  ]
-  ```
+    ```
+
+3. Add the following Policy to `MY-UPPY-USER`:
+
+   (if you don’t want to enable signing on the client, you can skip this step)
+
+    ```json
+    {
+        "Version": "2012-10-17",
+        "Statement": [
+            {
+                "Sid": "MyStsPolicyStatement1",
+                "Effect": "Allow",
+                "Action": [
+                    "sts:GetFederationToken"
+                ],
+                "Resource": [
+                    "arn:aws:sts::*:federated-user/*"
+                ]
+            }
+        ]
+    }
+    ```
 
 ### AWS Credentials
 
@@ -55,21 +99,6 @@ You may use existing AWS credentials or create a new user in the IAM page.
   [environment variables](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/loading-node-credentials-environment.html)
   or a
   [credentials file in `~/.aws/credentials`](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/setting-credentials-node.html).
-- You will need at least `PutObject` and `PutObjectAcl` permissions.
-
-```json
-{
-  "Version": "2012-10-17",
-  "Statement": [
-    {
-      "Sid": "VisualEditor0",
-      "Effect": "Allow",
-      "Action": ["s3:PutObject", "s3:PutObjectAcl"],
-      "Resource": "arn:aws:s3:::aws-nodejs/*"
-    }
-  ]
-}
-```
 
 ## Prerequisites
 
@@ -83,7 +112,7 @@ Add a `.env` file to the root directory and define the S3 bucket name and port
 variables like the example below:
 
 ```
-COMPANION_AWS_BUCKET=aws-nodejs
+COMPANION_AWS_BUCKET=MY-UPPY-BUCKET
 COMPANION_AWS_REGION=…
 COMPANION_AWS_KEY=…
 COMPANION_AWS_SECRET=…
@@ -104,6 +133,4 @@ corepack yarn workspace @uppy-example/aws-nodejs start
 
 Dashboard demo should now be available at http://localhost:8080.
 
-You have also a Drag & Drop demo on http://localhost:8080/drag.
-
 _Feel free to check how the demo works and feel free to open an issue._