Add httpAuthSchemeMiddleware to select an auth scheme

[syall]

Issue #, if available:

N/A.

Description of changes:

Dependent on: #948, #949

This PR has changes to codegen httpAuthSchemeMiddleware.

• Add memoizeIdentityProvider() for normalizing and memoizing config identity properties
• Allow DefaultIdentityProviderConfig to accept undefined properties
• Add the httpAuthSchemeMiddleware implementation to select an auth scheme
• Codegen service-specific interface for HttpAuthSchemeParametersProvider
• Codegen httpAuthSchemeMiddleware and refactor ConfigField codegen
  • Codegen httpAuthSchemeMiddleware, and also generate resolveHttpAuthSchemeConfig and input / resolved config interfaces.
  • resolveHttpAuthSchemeConfig normalizes ConfigField values, and for the "main" ConfigFields, the property is mapped in DefaultIdentityProviderConfig.
  • ConfigField codegen is removed from ServiceBareBonesClientGenerator and is moved to AddHttpAuthSchemeMiddleware::addConfigInterfaceFields().

Testing:

Note: all changes are gated by the experimentalIdentityAndAuth flag

The codegen diff is as follows:

diff --color -Nur /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/WeatherClient.ts /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/WeatherClient.ts
--- /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/WeatherClient.ts	2023-09-20 13:49:32
+++ /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/WeatherClient.ts	2023-09-20 13:50:03
@@ -1,6 +1,11 @@
 // smithy-typescript generated code
-import { WeatherHttpAuthSchemeProvider } from "./auth/httpAuthSchemeProvider";
 import {
+  HttpAuthSchemeInputConfig,
+  HttpAuthSchemeResolvedConfig,
+  WeatherHttpAuthSchemeProvider,
+  resolveHttpAuthSchemeConfig,
+} from "./auth/httpAuthSchemeProvider";
+import {
   CreateCityCommandInput,
   CreateCityCommandOutput,
 } from "./commands/CreateCityCommand";
@@ -104,11 +109,8 @@
   resolveEventStreamSerdeConfig,
 } from "@smithy/eventstream-serde-config-resolver";
 import {
-  ApiKeyIdentity,
-  ApiKeyIdentityProvider,
   HttpAuthScheme,
-  TokenIdentity,
-  TokenIdentityProvider,
+  getHttpAuthSchemePlugin,
   getHttpSigningPlugin,
 } from "@smithy/experimental-identity-and-auth";
 import { getContentLengthPlugin } from "@smithy/middleware-content-length";
@@ -131,8 +133,6 @@
   SmithyResolvedConfiguration as __SmithyResolvedConfiguration,
 } from "@smithy/smithy-client";
 import {
-  AwsCredentialIdentity,
-  AwsCredentialIdentityProvider,
   BodyLengthCalculator as __BodyLengthCalculator,
   CheckOptionalClientConfig as __CheckOptionalClientConfig,
   Checksum as __Checksum,
@@ -274,18 +274,6 @@
   disableHostPrefix?: boolean;
 
   /**
-   * experimentalIdentityAndAuth: Configuration of HttpAuthSchemes for a client which provides default identity providers and signers per auth scheme.
-   * @internal
-   */
-  httpAuthSchemes?: HttpAuthScheme[];
-
-  /**
-   * experimentalIdentityAndAuth: Configuration of an HttpAuthSchemeProvider for a client which resolves which HttpAuthScheme to use.
-   * @internal
-   */
-  httpAuthSchemeProvider?: WeatherHttpAuthSchemeProvider;
-
-  /**
    * Value for how many times a request will be made at most in case of retry.
    */
   maxAttempts?: number | __Provider<number>;
@@ -330,31 +318,23 @@
   defaultsMode?: __DefaultsMode | __Provider<__DefaultsMode>;
 
   /**
-   * The internal function that inject utilities to runtime-specific stream to help users consume the data
+   * experimentalIdentityAndAuth: Configuration of HttpAuthSchemes for a client which provides default identity providers and signers per auth scheme.
    * @internal
    */
-  sdkStreamMixin?: __SdkStreamMixinInjector;
+  httpAuthSchemes?: HttpAuthScheme[];
 
   /**
-   * The API key to use when making requests.
+   * experimentalIdentityAndAuth: Configuration of an HttpAuthSchemeProvider for a client which resolves which HttpAuthScheme to use.
+   * @internal
    */
-  apiKey?: ApiKeyIdentity | ApiKeyIdentityProvider;
+  httpAuthSchemeProvider?: WeatherHttpAuthSchemeProvider;
 
   /**
-   * The credentials used to sign requests.
+   * The internal function that inject utilities to runtime-specific stream to help users consume the data
+   * @internal
    */
-  credentials?: AwsCredentialIdentity | AwsCredentialIdentityProvider;
+  sdkStreamMixin?: __SdkStreamMixinInjector;
 
-  /**
-   * The AWS region to which this client will send requests.
-   */
-  region?: string | __Provider<string>;
-
-  /**
-   * The token used to authenticate requests.
-   */
-  token?: TokenIdentity | TokenIdentityProvider;
-
 }
 
 /**
@@ -367,6 +347,7 @@
   & CustomEndpointsInputConfig
   & RetryInputConfig
   & EventStreamSerdeInputConfig
+  & HttpAuthSchemeInputConfig
   & ClientInputEndpointParameters
 /**
  * @public
@@ -386,6 +367,7 @@
   & CustomEndpointsResolvedConfig
   & RetryResolvedConfig
   & EventStreamSerdeResolvedConfig
+  & HttpAuthSchemeResolvedConfig
   & ClientResolvedEndpointParameters
 /**
  * @public
@@ -417,11 +399,13 @@
     let _config_4 = resolveCustomEndpointsConfig(_config_3);
     let _config_5 = resolveRetryConfig(_config_4);
     let _config_6 = resolveEventStreamSerdeConfig(_config_5);
-    let _config_7 = resolveRuntimeExtensions(_config_6, configuration?.extensions || []);
-    super(_config_7);
-    this.config = _config_7;
+    let _config_7 = resolveHttpAuthSchemeConfig(_config_6);
+    let _config_8 = resolveRuntimeExtensions(_config_7, configuration?.extensions || []);
+    super(_config_8);
+    this.config = _config_8;
     this.middlewareStack.use(getRetryPlugin(this.config));
     this.middlewareStack.use(getContentLengthPlugin(this.config));
+    this.middlewareStack.use(getHttpAuthSchemePlugin(this.config));
     this.middlewareStack.use(getHttpSigningPlugin(this.config));
   }
 
diff --color -Nur /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/auth/httpAuthSchemeProvider.ts /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/auth/httpAuthSchemeProvider.ts
--- /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/auth/httpAuthSchemeProvider.ts	2023-09-20 13:49:32
+++ /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/auth/httpAuthSchemeProvider.ts	2023-09-20 13:50:03
@@ -1,13 +1,27 @@
 // smithy-typescript generated code
 import { WeatherClientResolvedConfig } from "../WeatherClient";
 import {
+  ApiKeyIdentity,
+  ApiKeyIdentityProvider,
+  DefaultIdentityProviderConfig,
   HttpApiKeyAuthLocation,
   HttpAuthOption,
   HttpAuthSchemeParameters,
   HttpAuthSchemeParametersProvider,
   HttpAuthSchemeProvider,
+  IdentityProviderConfig,
+  TokenIdentity,
+  TokenIdentityProvider,
+  doesIdentityRequireRefresh,
+  isIdentityExpired,
+  memoizeIdentityProvider,
 } from "@smithy/experimental-identity-and-auth";
 import {
+  AwsCredentialIdentity,
+  AwsCredentialIdentityProvider,
+  Provider as __Provider,
+} from "@smithy/types";
+import {
   getSmithyContext,
   normalizeProvider,
 } from "@smithy/util-middleware";
@@ -22,7 +36,12 @@
 /**
  * @internal
  */
-export const defaultWeatherHttpAuthSchemeParametersProvider: HttpAuthSchemeParametersProvider<WeatherClientResolvedConfig, WeatherHttpAuthSchemeParameters> = async (config, context) => {
+export interface WeatherHttpAuthSchemeParametersProvider extends HttpAuthSchemeParametersProvider<WeatherClientResolvedConfig, WeatherHttpAuthSchemeParameters> {}
+
+/**
+ * @internal
+ */
+export const defaultWeatherHttpAuthSchemeParametersProvider: WeatherHttpAuthSchemeParametersProvider = async (config, context, input) => {
   return {
     operation: getSmithyContext(context).operation as string,
     region: await normalizeProvider(config.region)() || (() => {
@@ -128,4 +147,81 @@
     };
   };
   return options;
+};
+
+/**
+ * @internal
+ */
+export interface HttpAuthSchemeInputConfig {
+  /**
+   * The API key to use when making requests.
+   */
+  apiKey?: ApiKeyIdentity | ApiKeyIdentityProvider;
+  /**
+   * The credentials used to sign requests.
+   */
+  credentials?: AwsCredentialIdentity | AwsCredentialIdentityProvider;
+  /**
+   * The AWS region to which this client will send requests.
+   */
+  region?: string | __Provider<string>;
+  /**
+   * The token used to authenticate requests.
+   */
+  token?: TokenIdentity | TokenIdentityProvider;
+}
+
+/**
+ * @internal
+ */
+export interface HttpAuthSchemeResolvedConfig {
+  /**
+   * The API key to use when making requests.
+   */
+  readonly apiKey?: ApiKeyIdentityProvider;
+  /**
+   * The credentials used to sign requests.
+   */
+  readonly credentials?: AwsCredentialIdentityProvider;
+  /**
+   * The AWS region to which this client will send requests.
+   */
+  readonly region?: __Provider<string>;
+  /**
+   * The token used to authenticate requests.
+   */
+  readonly token?: TokenIdentityProvider;
+  /**
+   * experimentalIdentityAndAuth: provides parameters for HttpAuthSchemeProvider.
+   * @internal
+   */
+  readonly httpAuthSchemeParametersProvider: WeatherHttpAuthSchemeParametersProvider;
+  /**
+   * experimentalIdentityAndAuth: abstraction around identity configuration fields
+   * @internal
+   */
+  readonly identityProviderConfig: IdentityProviderConfig;
+}
+
+/**
+ * @internal
+ */
+export const resolveHttpAuthSchemeConfig = (config: HttpAuthSchemeInputConfig): HttpAuthSchemeResolvedConfig => {
+  const apiKey = memoizeIdentityProvider(config.apiKey, isIdentityExpired, doesIdentityRequireRefresh);
+  const credentials = memoizeIdentityProvider(config.credentials, isIdentityExpired, doesIdentityRequireRefresh);
+  const region = config.region ? normalizeProvider(config.region) : undefined;
+  const token = memoizeIdentityProvider(config.token, isIdentityExpired, doesIdentityRequireRefresh);
+  return {
+    ...config,
+    apiKey,
+    credentials,
+    region,
+    token,
+    httpAuthSchemeParametersProvider: defaultWeatherHttpAuthSchemeParametersProvider,
+    identityProviderConfig: new DefaultIdentityProviderConfig({
+      "aws.auth#sigv4": credentials,
+      "smithy.api#httpApiKeyAuth": apiKey,
+      "smithy.api#httpBearerAuth": token,
+    }),
+  };
 };

If one or more of the packages in the /packages directory has been modified, be sure yarn changeset add has been run and its output has
been committed and included in this pull request. See CONTRIBUTING.md.

---

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[syall]

This is moved into AddHttpAuthSchemeMiddleware::addConfigInterfaceFields()

[syall]

This is moved into AddHttpAuthSchemeMiddleware::customize() where the following interfaces and function are generated:

• HttpAuthSchemeInputConfig
• HttpAuthSchemeResolvedConfig
• resolveHttpAuthSchemeConfig

[syall]

This is based on memoize() in @smithy/property-provider, except:

• it also handles undefined values.
• passes in options from MemoizedIdentityProvider to each call of the initial supplied provider.