chore(middleware-flexible-checksums): add config resolver

packages/middleware-flexible-checksums/package.json

@@ -35,6 +35,7 @@
     "@smithy/node-config-provider": "^3.1.5",
     "@smithy/protocol-http": "^4.1.1",
     "@smithy/types": "^3.4.0",
+    "@smithy/util-middleware": "^3.0.4",
     "@smithy/util-utf8": "^3.0.0",
     "tslib": "^2.6.2"
   },

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

@@ -1,11 +1,10 @@
 import { LoadedConfigSelectors } from "@smithy/node-config-provider";
 
-import { RequestChecksumCalculation } from "./constants";
+import { DEFAULT_REQUEST_CHECKSUM_CALCULATION, RequestChecksumCalculation } from "./constants";
 import { SelectorType, stringUnionSelector } from "./stringUnionSelector";
 
 export const ENV_REQUEST_CHECKSUM_CALCULATION = "AWS_REQUEST_CHECKSUM_CALCULATION";
 export const CONFIG_REQUEST_CHECKSUM_CALCULATION = "request_checksum_calculation";
-export const DEFAULT_REQUEST_CHECKSUM_CALCULATION = RequestChecksumCalculation.WHEN_SUPPORTED;
 
 export const NODE_REQUEST_CHECKSUM_CALCULATION_CONFIG_OPTIONS: LoadedConfigSelectors<string> = {
   environmentVariableSelector: (env) =>

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

@@ -1,11 +1,10 @@
 import { LoadedConfigSelectors } from "@smithy/node-config-provider";
 
-import { RequestChecksumCalculation } from "./constants";
+import { DEFAULT_RESPONSE_CHECKSUM_VALIDATION, RequestChecksumCalculation } from "./constants";
 import { SelectorType, stringUnionSelector } from "./stringUnionSelector";
 
 export const ENV_RESPONSE_CHECKSUM_VALIDATION = "AWS_RESPONSE_CHECKSUM_VALIDATION";
 export const CONFIG_RESPONSE_CHECKSUM_VALIDATION = "response_checksum_validation";
-export const DEFAULT_RESPONSE_CHECKSUM_VALIDATION = RequestChecksumCalculation.WHEN_SUPPORTED;
 
 export const NODE_RESPONSE_CHECKSUM_VALIDATION_CONFIG_OPTIONS: LoadedConfigSelectors<string> = {
   environmentVariableSelector: (env) =>

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

@@ -21,6 +21,8 @@ export const RequestChecksumCalculation = {
 
 export type RequestChecksumCalculation = (typeof RequestChecksumCalculation)[keyof typeof RequestChecksumCalculation];
 
+export const DEFAULT_REQUEST_CHECKSUM_CALCULATION = RequestChecksumCalculation.WHEN_SUPPORTED;
+
 /**
  * Determines when checksum validation will be performed on response payloads.
  */
@@ -44,6 +46,8 @@ export const ResponseChecksumValidation = {
 
 export type ResponseChecksumValidation = (typeof ResponseChecksumValidation)[keyof typeof ResponseChecksumValidation];
 
+export const DEFAULT_RESPONSE_CHECKSUM_VALIDATION = RequestChecksumCalculation.WHEN_SUPPORTED;
+
 /**
  * Checksum Algorithms supported by the SDK.
  */

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

@@ -3,3 +3,4 @@ export * from "./NODE_RESPONSE_CHECKSUM_VALIDATION_CONFIG_OPTIONS";
 export * from "./constants";
 export * from "./flexibleChecksumsMiddleware";
 export * from "./getFlexibleChecksumsPlugin";
+export * from "./resolveFlexibleChecksumsConfig";

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

@@ -0,0 +1,35 @@
+import { normalizeProvider } from "@smithy/util-middleware";
+
+import { DEFAULT_REQUEST_CHECKSUM_CALCULATION, DEFAULT_RESPONSE_CHECKSUM_VALIDATION } from "./constants";
+import { resolveFlexibleChecksumsConfig } from "./resolveFlexibleChecksumsConfig";
+
+jest.mock("@smithy/util-middleware");
+
+describe(resolveFlexibleChecksumsConfig.name, () => {
+  beforeEach(() => {
+    (normalizeProvider as jest.Mock).mockImplementation((input) => input);
+  });
+
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it("returns default client checksums configuration, if not provided", () => {
+    const resolvedConfig = resolveFlexibleChecksumsConfig({});
+    expect(resolvedConfig).toEqual({
+      requestChecksumCalculation: DEFAULT_REQUEST_CHECKSUM_CALCULATION,
+      responseChecksumValidation: DEFAULT_RESPONSE_CHECKSUM_VALIDATION,
+    });
+    expect(normalizeProvider).toHaveBeenCalledTimes(2);
+  });
+
+  it("normalizes client checksums configuration", () => {
+    const mockInput = {
+      requestChecksumCalculation: "WHEN_REQUIRED",
+      responseChecksumValidation: "WHEN_REQUIRED",
+    };
+    const resolvedConfig = resolveFlexibleChecksumsConfig(mockInput);
+    expect(resolvedConfig).toEqual(mockInput);
+    expect(normalizeProvider).toHaveBeenCalledTimes(2);
+  });
+});

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

@@ -0,0 +1,33 @@
+import { Provider } from "@smithy/types";
+import { normalizeProvider } from "@smithy/util-middleware";
+
+import { DEFAULT_REQUEST_CHECKSUM_CALCULATION, DEFAULT_RESPONSE_CHECKSUM_VALIDATION } from "./constants";
+
+export interface FlexibleChecksumsInputConfig {
+  /**
+   * Determines when a checksum will be calculated for request payloads.
+   */
+  requestChecksumCalculation?: string | Provider<string>;
+
+  /**
+   * Determines when checksum validation will be performed on response payloads.
+   */
+  responseChecksumValidation?: string | Provider<string>;
+}
+
+export interface FlexibleChecksumsResolvedConfig {
+  requestChecksumCalculation: Provider<string>;
+  responseChecksumValidation: Provider<string>;
+}
+
+export const resolveFlexibleChecksumsConfig = <T>(
+  input: T & FlexibleChecksumsInputConfig
+): T & FlexibleChecksumsResolvedConfig => ({
+  ...input,
+  requestChecksumCalculation: normalizeProvider(
+    input.requestChecksumCalculation ?? DEFAULT_REQUEST_CHECKSUM_CALCULATION
+  ),
+  responseChecksumValidation: normalizeProvider(
+    input.responseChecksumValidation ?? DEFAULT_RESPONSE_CHECKSUM_VALIDATION
+  ),
+});