docs(supplemental-docs): version update for JSv3

Author: siddsriv

packages/middleware-flexible-checksums/src/middleware-md5-fallback.e2e.spec.ts

@@ -13,6 +13,7 @@ describe("S3 MD5 Fallback for DeleteObjects", () => {
   let s3: S3;
   let Bucket: string;
   const testFiles = ["md5-test-1.txt", "md5-test-2.txt"];
+  const md5Hash = createHash("md5");
 
   beforeAll(async () => {
     s3 = new S3({ region: "us-west-2" });
@@ -73,16 +74,15 @@ describe("S3 MD5 Fallback for DeleteObjects", () => {
     let crc32Removed = false;
 
     md5S3Client.middlewareStack.add(
-      (next) => async (args) => {
+      (next, context) => async (args) => {
         // Check if this is a DeleteObjects command
-        const isDeleteObjects = args.constructor?.name === "DeleteObjectsCommand" || args.input?.Delete !== undefined;
+        const isDeleteObjects = context.commandName === "DeleteObjects";
 
         if (!isDeleteObjects) {
           return next(args);
         }
 
         const result = await next(args);
-
         const headers = args.request.headers;
 
         // Remove checksum headers
@@ -99,8 +99,7 @@ describe("S3 MD5 Fallback for DeleteObjects", () => {
         // Add MD5
         if (args.request.body) {
           const bodyContent = Buffer.from(args.request.body);
-          const md5Hash = createHash("md5").update(bodyContent).digest("base64");
-          headers["Content-MD5"] = md5Hash;
+          headers["Content-MD5"] = md5Hash.update(bodyContent).digest("base64");
           md5Added = true;
         }
 

supplemental-docs/MD5_FALLBACK.md

@@ -2,13 +2,15 @@
 
 ## Background
 
-Recently the AWS SDKs shipped a feature that [changed default object integrity in S3](https://github.com/aws/aws-sdk-js-v3/issues/6810). The SDKs now default to using more modern checksums (like CRC32) to ensure object integrity, whereas previously MD5 checksums were being used. Some third-party S3-compatible services currently do not support these checksums. To our knowledge, this affects only the S3 `DeleteObjects` operation.
+In AWS SDK for JavaScript [v3.729.0](https://github.com/aws/aws-sdk-js-v3/releases/tag/v3.729.0), we shipped a feature that [changed default object integrity in S3](https://github.com/aws/aws-sdk-js-v3/issues/6810). The SDKs now default to using more modern checksums (like CRC32) to ensure object integrity, whereas previously MD5 checksums were being used. Some third-party S3-compatible services currently do not support these checksums. To our knowledge, this affects only the S3 `DeleteObjects` operation.
 
-If you wish to fallback to the old behavior of sending MD5 checksums, for operations like `DeleteObjectsCommand` this is how you can do it in AWS SDK for JavaScript v3:
+If you wish to fallback to the old behavior of sending MD5 checksums, for operations like `DeleteObjectsCommand` this is how
+you can do it in AWS SDK for JavaScript v3:
 
 ## MD5 fallback
 
-The following code provides a custom S3 client that will use MD5 checksums for DeleteObjects operations while maintaining the default behavior for all other operations.
+The following code provides a custom S3 client that will use MD5 checksums for DeleteObjects operations while maintaining the
+default behavior for all other operations.
 
 ```javascript
 // md5ClientS3.mjs
@@ -20,19 +22,18 @@ import { createHash } from "crypto";
  */
 export function createS3ClientWithMD5() {
   const client = new S3Client({});
+  const md5Hash = createHash("md5");
 
   client.middlewareStack.add(
-    (next) => async (args) => {
+    (next, context) => async (args) => {
       // Check if this is a DeleteObjects command
-      const isDeleteObjects = args.constructor?.name === "DeleteObjectsCommand" || args.input?.Delete !== undefined;
+      const isDeleteObjects = context.commandName === "DeleteObjects";
 
       if (!isDeleteObjects) {
         return next(args);
       }
 
       const result = await next(args);
-
-      // Modify the final request headers
       const headers = args.request.headers;
 
       // Remove any checksum headers
@@ -45,17 +46,16 @@ export function createS3ClientWithMD5() {
         }
       });
 
-      // Calculate and add MD5 for the request body
+      // Add MD5
       if (args.request.body) {
         const bodyContent = Buffer.from(args.request.body);
-        const md5Hash = createHash("md5").update(bodyContent).digest("base64");
-        headers["Content-MD5"] = md5Hash;
+        headers["Content-MD5"] = md5Hash.update(bodyContent).digest("base64");
       }
 
       return result;
     },
     {
-      step: "finalizeRequest", // Run after all other request modifications
+      step: "finalizeRequest",
       name: "addMD5Checksum",
     }
   );
@@ -95,13 +95,13 @@ try {
 
 The solution adds middleware to the S3 client that:
 
-1. Detects DeleteObjects operations
+1. Detects DeleteObjects operations using the command name
 2. Lets the SDK add its default headers
 3. Removes any checksum headers in the finalizeRequest step
 4. Calculates an MD5 hash of the request body
 5. Adds the MD5 hash as a Content-MD5 header
 
-This sequence ensures that we properly replace the current checksums with the MD5 checksum.
+This sequence ensures that we properly replace the checksums with MD5 checksum.
 
 ## Usage Notes
 
@@ -110,7 +110,8 @@ This sequence ensures that we properly replace the current checksums with the MD
 
 ## Debugging
 
-To verify that the MD5 checksum is being correctly applied, you can add console logging to the middleware by modifying the code to include logging statements:
+To verify that the MD5 checksum is being correctly applied, you can add console logging to the middleware by modifying the
+code to include logging statements:
 
 ```javascript
 // Inside the middleware function, add: