chore(middleware-flexible-checksums): use ResponseChecksumValidation

Author: trivikr

packages/middleware-flexible-checksums/src/configuration.ts

@@ -37,6 +37,11 @@ export interface PreviouslyResolved {
    */
   requestChecksumCalculation: Provider<string>;
 
+  /**
+   * Determines when a checksum will be calculated for response payloads
+   */
+  responseChecksumValidation: Provider<string>;
+
   /**
    * A constructor for a class implementing the {@link Hash} interface that computes SHA1 hashes.
    * @internal

packages/middleware-flexible-checksums/src/flexibleChecksumsResponseMiddleware.spec.ts

@@ -2,7 +2,7 @@ import { HttpRequest } from "@smithy/protocol-http";
 import { DeserializeHandlerArguments } from "@smithy/types";
 
 import { PreviouslyResolved } from "./configuration";
-import { ChecksumAlgorithm } from "./constants";
+import { ChecksumAlgorithm, ResponseChecksumValidation } from "./constants";
 import { flexibleChecksumsResponseMiddleware } from "./flexibleChecksumsResponseMiddleware";
 import { getChecksumLocationName } from "./getChecksumLocationName";
 import { FlexibleChecksumsMiddlewareConfig } from "./getFlexibleChecksumsPlugin";
@@ -23,7 +23,9 @@ describe(flexibleChecksumsResponseMiddleware.name, () => {
     commandName: "mockCommandName",
   };
 
-  const mockConfig = {} as PreviouslyResolved;
+  const mockConfig = {
+    responseChecksumValidation: () => Promise.resolve(ResponseChecksumValidation.WHEN_REQUIRED),
+  } as PreviouslyResolved;
   const mockRequestValidationModeMember = "ChecksumEnabled";
   const mockResponseAlgorithms = [ChecksumAlgorithm.CRC32, ChecksumAlgorithm.CRC32C];
   const mockMiddlewareConfig = {
@@ -65,6 +67,7 @@ describe(flexibleChecksumsResponseMiddleware.name, () => {
       const handler = flexibleChecksumsResponseMiddleware(mockConfig, mockMiddlewareConfig)(mockNext, mockContext);
       await handler(mockArgs);
       expect(validateChecksumFromResponse).not.toHaveBeenCalled();
+      expect(mockNext).toHaveBeenCalledWith(mockArgs);
     });
 
     describe("response checksum", () => {
@@ -74,12 +77,16 @@ describe(flexibleChecksumsResponseMiddleware.name, () => {
         const handler = flexibleChecksumsResponseMiddleware(mockConfig, mockMwConfig)(mockNext, mockContext);
         await handler(mockArgs);
         expect(validateChecksumFromResponse).not.toHaveBeenCalled();
+        expect(mockNext).toHaveBeenCalledWith(mockArgs);
       });
 
       it("if requestValidationModeMember is not enabled in input", async () => {
         const handler = flexibleChecksumsResponseMiddleware(mockConfig, mockMiddlewareConfig)(mockNext, mockContext);
-        await handler({ ...mockArgs, input: {} });
+
+        const mockArgsWithoutEnabled = { ...mockArgs, input: {} };
+        await handler(mockArgsWithoutEnabled);
         expect(validateChecksumFromResponse).not.toHaveBeenCalled();
+        expect(mockNext).toHaveBeenCalledWith(mockArgsWithoutEnabled);
       });
 
       it("if checksum is for S3 whole-object multipart GET", async () => {
@@ -92,19 +99,39 @@ describe(flexibleChecksumsResponseMiddleware.name, () => {
         expect(isChecksumWithPartNumber).toHaveBeenCalledTimes(1);
         expect(isChecksumWithPartNumber).toHaveBeenCalledWith(mockChecksum);
         expect(validateChecksumFromResponse).not.toHaveBeenCalled();
+        expect(mockNext).toHaveBeenCalledWith(mockArgs);
       });
     });
   });
 
   describe("validates checksum from response header", () => {
-    it("generic case", async () => {
+    it("if requestValidationModeMember is enabled in input", async () => {
       const handler = flexibleChecksumsResponseMiddleware(mockConfig, mockMiddlewareConfig)(mockNext, mockContext);
 
       await handler(mockArgs);
       expect(validateChecksumFromResponse).toHaveBeenCalledWith(mockResult.response, {
         config: mockConfig,
         responseAlgorithms: mockResponseAlgorithms,
       });
+      expect(mockNext).toHaveBeenCalledWith(mockArgs);
+    });
+
+    it(`if requestValidationModeMember is not enabled in input, but responseChecksumValidation returns ${ResponseChecksumValidation.WHEN_SUPPORTED}`, async () => {
+      const mockConfigWithResponseChecksumValidationSupported = {
+        ...mockConfig,
+        responseChecksumValidation: () => Promise.resolve(ResponseChecksumValidation.WHEN_SUPPORTED),
+      };
+      const handler = flexibleChecksumsResponseMiddleware(
+        mockConfigWithResponseChecksumValidationSupported,
+        mockMiddlewareConfig
+      )(mockNext, mockContext);
+
+      await handler({ ...mockArgs, input: {} });
+      expect(validateChecksumFromResponse).toHaveBeenCalledWith(mockResult.response, {
+        config: mockConfigWithResponseChecksumValidationSupported,
+        responseAlgorithms: mockResponseAlgorithms,
+      });
+      expect(mockNext).toHaveBeenCalledWith(mockArgs);
     });
 
     it("if checksum is for S3 GET without part number", async () => {
@@ -120,6 +147,7 @@ describe(flexibleChecksumsResponseMiddleware.name, () => {
         config: mockConfig,
         responseAlgorithms: mockResponseAlgorithms,
       });
+      expect(mockNext).toHaveBeenCalledWith(mockArgs);
     });
   });
 });

packages/middleware-flexible-checksums/src/flexibleChecksumsResponseMiddleware.ts

@@ -10,7 +10,7 @@ import {
 } from "@smithy/types";
 
 import { PreviouslyResolved } from "./configuration";
-import { ChecksumAlgorithm } from "./constants";
+import { ChecksumAlgorithm, ResponseChecksumValidation } from "./constants";
 import { getChecksumAlgorithmListForResponse } from "./getChecksumAlgorithmListForResponse";
 import { getChecksumLocationName } from "./getChecksumLocationName";
 import { isChecksumWithPartNumber } from "./isChecksumWithPartNumber";
@@ -63,14 +63,24 @@ export const flexibleChecksumsResponseMiddleware =
     }
 
     const input = args.input;
+    const { requestValidationModeMember, responseAlgorithms } = middlewareConfig;
+    const responseChecksumValidation = await config.responseChecksumValidation();
+
+    const isResponseChecksumValidationNeeded =
+      requestValidationModeMember &&
+      (input[requestValidationModeMember] === "ENABLED" ||
+        responseChecksumValidation === ResponseChecksumValidation.WHEN_SUPPORTED);
+
+    if (isResponseChecksumValidationNeeded) {
+      input[requestValidationModeMember] = "ENABLED";
+    }
+
     const result = await next(args);
 
     const response = result.response as HttpResponse;
     let collectedStream: Uint8Array | undefined = undefined;
 
-    const { requestValidationModeMember, responseAlgorithms } = middlewareConfig;
-    // @ts-ignore Element implicitly has an 'any' type for input[requestValidationModeMember]
-    if (requestValidationModeMember && input[requestValidationModeMember] === "ENABLED") {
+    if (isResponseChecksumValidationNeeded) {
       const { clientName, commandName } = context;
       const isS3WholeObjectMultipartGetResponseChecksum =
         clientName === "S3Client" &&