Add extracted source directory and README navigation

extracted-source/node_modules/@azure/msal-node/dist/client/ManagedIdentitySources/AppService.mjs

@@ -0,0 +1,109 @@
+/*! @azure/msal-node v3.8.1 2025-10-29 */
+'use strict';
+import { BaseManagedIdentitySource } from './BaseManagedIdentitySource.mjs';
+import { ManagedIdentityEnvironmentVariableNames, ManagedIdentitySourceNames, ManagedIdentityHeaders, ManagedIdentityQueryParameters, ManagedIdentityIdType, HttpMethod } from '../../utils/Constants.mjs';
+import { ManagedIdentityRequestParameters } from '../../config/ManagedIdentityRequestParameters.mjs';
+
+/*
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License.
+ */
+// MSI Constants. Docs for MSI are available here https://docs.microsoft.com/azure/app-service/overview-managed-identity
+const APP_SERVICE_MSI_API_VERSION = "2019-08-01";
+/**
+ * Azure App Service Managed Identity Source implementation.
+ *
+ * This class provides managed identity authentication for applications running in Azure App Service.
+ * It uses the local metadata service endpoint available within App Service environments to obtain
+ * access tokens without requiring explicit credentials.
+ *
+ * Original source of code: https://github.com/Azure/azure-sdk-for-net/blob/main/sdk/identity/Azure.Identity/src/AppServiceManagedIdentitySource.cs
+ */
+class AppService extends BaseManagedIdentitySource {
+    /**
+     * Creates a new instance of the AppService managed identity source.
+     *
+     * @param logger - Logger instance for diagnostic output
+     * @param nodeStorage - Node.js storage implementation for caching
+     * @param networkClient - Network client for making HTTP requests
+     * @param cryptoProvider - Cryptographic operations provider
+     * @param disableInternalRetries - Whether to disable internal retry logic
+     * @param identityEndpoint - The App Service identity endpoint URL
+     * @param identityHeader - The secret header value required for authentication
+     */
+    constructor(logger, nodeStorage, networkClient, cryptoProvider, disableInternalRetries, identityEndpoint, identityHeader) {
+        super(logger, nodeStorage, networkClient, cryptoProvider, disableInternalRetries);
+        this.identityEndpoint = identityEndpoint;
+        this.identityHeader = identityHeader;
+    }
+    /**
+     * Retrieves the required environment variables for App Service managed identity.
+     *
+     * App Service managed identity requires two environment variables:
+     * - IDENTITY_ENDPOINT: The URL of the local metadata service
+     * - IDENTITY_HEADER: A secret header value for authentication
+     *
+     * @returns An array containing [identityEndpoint, identityHeader] values from environment variables.
+     *          Either value may be undefined if the environment variable is not set.
+     */
+    static getEnvironmentVariables() {
+        const identityEndpoint = process.env[ManagedIdentityEnvironmentVariableNames.IDENTITY_ENDPOINT];
+        const identityHeader = process.env[ManagedIdentityEnvironmentVariableNames.IDENTITY_HEADER];
+        return [identityEndpoint, identityHeader];
+    }
+    /**
+     * Attempts to create an AppService managed identity source if the environment supports it.
+     *
+     * This method checks for the presence of required environment variables and validates
+     * the identity endpoint URL. If the environment is not suitable for App Service managed
+     * identity (missing environment variables or invalid endpoint), it returns null.
+     *
+     * @param logger - Logger instance for diagnostic output
+     * @param nodeStorage - Node.js storage implementation for caching
+     * @param networkClient - Network client for making HTTP requests
+     * @param cryptoProvider - Cryptographic operations provider
+     * @param disableInternalRetries - Whether to disable internal retry logic
+     *
+     * @returns A new AppService instance if the environment is suitable, null otherwise
+     */
+    static tryCreate(logger, nodeStorage, networkClient, cryptoProvider, disableInternalRetries) {
+        const [identityEndpoint, identityHeader] = AppService.getEnvironmentVariables();
+        // if either of the identity endpoint or identity header variables are undefined, this MSI provider is unavailable.
+        if (!identityEndpoint || !identityHeader) {
+            logger.info(`[Managed Identity] ${ManagedIdentitySourceNames.APP_SERVICE} managed identity is unavailable because one or both of the '${ManagedIdentityEnvironmentVariableNames.IDENTITY_HEADER}' and '${ManagedIdentityEnvironmentVariableNames.IDENTITY_ENDPOINT}' environment variables are not defined.`);
+            return null;
+        }
+        const validatedIdentityEndpoint = AppService.getValidatedEnvVariableUrlString(ManagedIdentityEnvironmentVariableNames.IDENTITY_ENDPOINT, identityEndpoint, ManagedIdentitySourceNames.APP_SERVICE, logger);
+        logger.info(`[Managed Identity] Environment variables validation passed for ${ManagedIdentitySourceNames.APP_SERVICE} managed identity. Endpoint URI: ${validatedIdentityEndpoint}. Creating ${ManagedIdentitySourceNames.APP_SERVICE} managed identity.`);
+        return new AppService(logger, nodeStorage, networkClient, cryptoProvider, disableInternalRetries, identityEndpoint, identityHeader);
+    }
+    /**
+     * Creates a managed identity token request for the App Service environment.
+     *
+     * This method constructs an HTTP GET request to the App Service identity endpoint
+     * with the required headers, query parameters, and managed identity configuration.
+     * The request includes the secret header for authentication and appropriate API version.
+     *
+     * @param resource - The target resource/scope for which to request an access token (e.g., "https://graph.microsoft.com/.default")
+     * @param managedIdentityId - The managed identity configuration specifying whether to use system-assigned or user-assigned identity
+     *
+     * @returns A configured ManagedIdentityRequestParameters object ready for network execution
+     */
+    createRequest(resource, managedIdentityId) {
+        const request = new ManagedIdentityRequestParameters(HttpMethod.GET, this.identityEndpoint);
+        request.headers[ManagedIdentityHeaders.APP_SERVICE_SECRET_HEADER_NAME] =
+            this.identityHeader;
+        request.queryParameters[ManagedIdentityQueryParameters.API_VERSION] =
+            APP_SERVICE_MSI_API_VERSION;
+        request.queryParameters[ManagedIdentityQueryParameters.RESOURCE] =
+            resource;
+        if (managedIdentityId.idType !== ManagedIdentityIdType.SYSTEM_ASSIGNED) {
+            request.queryParameters[this.getManagedIdentityUserAssignedIdQueryParameterKey(managedIdentityId.idType)] = managedIdentityId.id;
+        }
+        // bodyParameters calculated in BaseManagedIdentity.acquireTokenWithManagedIdentity
+        return request;
+    }
+}
+
+export { AppService };
+//# sourceMappingURL=AppService.mjs.map