fix(middleware-sdk-s3): only check tail bytes in s3-200-errors

Author: kuhe

packages/middleware-sdk-s3/src/throw-200-exceptions.ts

@@ -41,8 +41,8 @@ export const throw200ExceptionsMiddleware =
       return result;
     }
 
-    const bodyBytes = await collectBody(body, config);
-    const bodyString = await collectBodyString(bodyBytes, config);
+    const bodyBytes: Uint8Array = await collectBody(body, config);
+    const bodyStringTail = config.utf8Encoder(bodyBytes.subarray(bodyBytes.length - 16));
 
     // Throw on 200 response with empty body, legacy behavior allowlist.
     if (bodyBytes.length === 0 && THROW_IF_EMPTY_BODY[context.commandName!]) {
@@ -51,7 +51,7 @@ export const throw200ExceptionsMiddleware =
       throw err;
     }
     // Generalized throw-on-200 for top level Error element and non-streaming response.
-    if (bodyString && bodyString.endsWith("</Error>")) {
+    if (bodyStringTail && bodyStringTail.endsWith("</Error>")) {
       // Set the error code to 4XX so that error deserializer can parse them
       response.statusCode = 400;
     }
@@ -70,10 +70,6 @@ const collectBody = (streamBody: any = new Uint8Array(), context: PreviouslyReso
   return context.streamCollector(streamBody) || Promise.resolve(new Uint8Array());
 };
 
-// Encode Uint8Array data into string with utf-8.
-const collectBodyString = (streamBody: any, context: PreviouslyResolved): Promise<string> =>
-  collectBody(streamBody, context).then((body) => context.utf8Encoder(body));
-
 /**
  * @internal
  */

scripts/copy-smithy-dist-files.js

@@ -13,9 +13,13 @@ const smithyPackages = path.join(aws, "smithy-typescript", "packages");
 const node_modules = path.join(__dirname, "..", "node_modules");
 
 const localSmithyPkgs = fs.readdirSync(path.join(node_modules, "@smithy"));
+const adjacentSmithyPkgs = fs.readdirSync(smithyPackages);
 
 (async () => {
-  for (const smithyPkg of localSmithyPkgs) {
+  for (const smithyPkg of [...localSmithyPkgs, ...adjacentSmithyPkgs]) {
+    if (!fs.existsSync(path.join(smithyPackages, smithyPkg, "dist-cjs"))) {
+      continue;
+    }
     await Promise.all([
       spawnProcess("cp", [
         "-r",