Initiate cloud discovery in Constructor

lib/msal-core/src/UserAgentApplication.ts

@@ -220,8 +220,7 @@ export class UserAgentApplication {
 
         this.telemetryManager = this.getTelemetryManagerFromConfig(this.config.system.telemetry, this.clientId);
 
-        TrustedAuthority.setTrustedAuthoritiesFromConfig(this.config.auth.validateAuthority, this.config.auth.knownAuthorities);
-        AuthorityFactory.saveMetadataFromConfig(this.config.auth.authority, this.config.auth.authorityMetadata);
+        AuthorityFactory.initializeAuthorityData(this.config.auth, this.telemetryManager);
 
         // if no authority is passed, set the default: "https://login.microsoftonline.com/common"
         this.authority = this.config.auth.authority || DEFAULT_AUTHORITY;

lib/msal-core/src/authority/Authority.ts

@@ -144,9 +144,6 @@ export class Authority {
     public async resolveEndpointsAsync(telemetryManager: TelemetryManager, correlationId: string): Promise<ITenantDiscoveryResponse> {
         if (this.IsValidationEnabled) {
             const host = this.canonicalAuthorityUrlComponents.HostNameAndPort;
-            if (TrustedAuthority.getTrustedHostList().length === 0) {
-                await TrustedAuthority.setTrustedAuthoritiesFromNetwork(telemetryManager, correlationId);
-            }
 
             if (!TrustedAuthority.IsInTrustedHostList(host)) {
                 throw ClientConfigurationError.createUntrustedAuthorityError(host);

lib/msal-core/src/authority/AuthorityFactory.ts

@@ -11,11 +11,15 @@ import { StringUtils } from "../utils/StringUtils";
 import { ClientConfigurationError } from "../error/ClientConfigurationError";
 import { ITenantDiscoveryResponse, OpenIdConfiguration } from "./ITenantDiscoveryResponse";
 import TelemetryManager from "../telemetry/TelemetryManager";
+import { AuthOptions } from '../Configuration';
+import { TrustedAuthority } from './TrustedAuthority';
 
 export class AuthorityFactory {
     private static metadataMap = new Map<string, ITenantDiscoveryResponse>();
+    private static cloudInstanceDiscoveryPromise: Promise<void>;
 
     public static async saveMetadataFromNetwork(authorityInstance: Authority, telemetryManager: TelemetryManager, correlationId: string): Promise<ITenantDiscoveryResponse> {
+        await this.cloudInstanceDiscoveryPromise;
         const metadata = await authorityInstance.resolveEndpointsAsync(telemetryManager, correlationId);
         this.metadataMap.set(authorityInstance.CanonicalAuthority, metadata);
         return metadata;
@@ -45,6 +49,17 @@ export class AuthorityFactory {
         }
     }
 
+    /**
+     * 
+     * @param authConfig 
+     * @param telemetryManager 
+     */
+    public static initializeAuthorityData(authConfig: AuthOptions, telemetryManager: TelemetryManager) {
+        TrustedAuthority.setTrustedAuthoritiesFromConfig(authConfig.validateAuthority, authConfig.knownAuthorities);
+        this.saveMetadataFromConfig(authConfig.authority, authConfig.authorityMetadata);
+        this.cloudInstanceDiscoveryPromise = TrustedAuthority.setTrustedAuthoritiesFromNetwork(authConfig.validateAuthority, telemetryManager);
+    }
+
     /**
      * Create an authority object of the correct type based on the url
      * Performs basic authority validation - checks to see if the authority is of a valid type (eg aad, b2c)

lib/msal-core/src/authority/TrustedAuthority.ts

@@ -24,37 +24,36 @@ export class TrustedAuthority {
      * @param telemetryManager 
      * @param correlationId 
      */
-    private static async getAliases(telemetryManager: TelemetryManager, correlationId?: string): Promise<Array<any>> {
-        const client: XhrClient = new XhrClient();
+    public static setTrustedAuthoritiesFromNetwork(validateAuthority: boolean, telemetryManager: TelemetryManager, correlationId?: string): Promise<void> {
+        if (!validateAuthority || this.getTrustedHostList().length > 0) {
+            return Promise.resolve();
+        }
 
-        const httpMethod = "GET";
-        const httpEvent: HttpEvent = telemetryManager.createAndStartHttpEvent(correlationId, httpMethod, AAD_INSTANCE_DISCOVERY_ENDPOINT, "getAliases");
-        return client.sendRequestAsync(AAD_INSTANCE_DISCOVERY_ENDPOINT, httpMethod, true)
-            .then((response: XhrResponse) => {
-                httpEvent.httpResponseStatus = response.statusCode;
-                telemetryManager.stopEvent(httpEvent);
-                return response.body.metadata;
-            })
-            .catch(err => {
-                httpEvent.serverErrorCode = err;
-                telemetryManager.stopEvent(httpEvent);
-                throw err;
-            });
-    }
+        return new Promise<void>((resolve, reject) => {
+            const client: XhrClient = new XhrClient();
 
-    /**
-     * 
-     * @param telemetryManager 
-     * @param correlationId 
-     */
-    public static async setTrustedAuthoritiesFromNetwork(telemetryManager: TelemetryManager, correlationId?: string): Promise<void> {
-        const metadata = await this.getAliases(telemetryManager, correlationId);
-        metadata.forEach(function(entry: any){
-            const authorities: Array<string> = entry.aliases;
-            authorities.forEach(function(authority: string) {
-                TrustedAuthority.TrustedHostList.push(authority.toLowerCase());
-            });
-        });
+            const httpMethod = "GET";
+            const httpEvent: HttpEvent = telemetryManager.createAndStartHttpEvent(correlationId, httpMethod, AAD_INSTANCE_DISCOVERY_ENDPOINT, "getAliases");
+            client.sendRequestAsync(AAD_INSTANCE_DISCOVERY_ENDPOINT, httpMethod, true)
+                .then((response: XhrResponse) => {
+                    httpEvent.httpResponseStatus = response.statusCode;
+                    telemetryManager.stopEvent(httpEvent);
+
+                    response.body.metadata.forEach(function(entry: any){
+                        const authorities: Array<string> = entry.aliases;
+                        authorities.forEach(function(authority: string) {
+                            TrustedAuthority.TrustedHostList.push(authority.toLowerCase());
+                        });
+                    });
+
+                    resolve();
+                })
+                .catch(err => {
+                    httpEvent.serverErrorCode = err;
+                    telemetryManager.stopEvent(httpEvent);
+                    reject(err);
+                });
+        })
     } 
 
     public static getTrustedHostList(): Array<string> {