Allow to use custom adapter (#5067)

* Allow to use custom adapter

* fix: improve TypeScript documentation

adapters/oidc/js/src/main/resources/keycloak.d.ts

@@ -29,7 +29,7 @@ export = Keycloak;
 declare function Keycloak(config?: string|{}): Keycloak.KeycloakInstance;
 
 declare namespace Keycloak {
-	type KeycloakAdapterName = 'cordova'|'default';
+	type KeycloakAdapterName = 'cordova'|'default' | any;
 	type KeycloakOnLoad = 'login-required'|'check-sso';
 	type KeycloakResponseMode = 'query'|'fragment';
 	type KeycloakResponseType = 'code'|'id_token token'|'code id_token token';
@@ -42,7 +42,11 @@ declare namespace Keycloak {
 		useNonce?: boolean;
 
 		/**
-		 * @private Undocumented.
+		 * Allows to use different adapter:
+		 * 
+		 * - {string} default - using browser api for redirects
+		 * - {string} cordova - using cordova plugins 
+		 * - {function} - allows to provide custom function as adapter.
 		 */
 		adapter?: KeycloakAdapterName;
 		

adapters/oidc/js/src/main/resources/keycloak.js

@@ -51,6 +51,8 @@
                 adapter = loadAdapter('cordova');
             } else if (initOptions && initOptions.adapter === 'default') {
                 adapter = loadAdapter();
+            } else if (initOptions && typeof initOptions.adapter === "object") {
+                adapter = initOptions.adapter;
             } else {
                 if (window.Cordova || window.cordova) {
                     adapter = loadAdapter('cordova');