OIDC: Persist details in session storage, create store (#11302)

* utils to persist clientId and issuer after oidc authentication

* add dep oidc-client-ts

* persist issuer and clientId after successful oidc auth

* add OidcClientStore

* comments and tidy

* format

src/utils/oidc/authorize.ts

@@ -81,9 +81,12 @@ export const completeOidcLogin = async (
     homeserverUrl: string;
     identityServerUrl?: string;
     accessToken: string;
+    clientId: string;
+    issuer: string;
 }> => {
     const { code, state } = getCodeAndStateFromQueryParams(queryParams);
-    const { homeserverUrl, tokenResponse, identityServerUrl } = await completeAuthorizationCodeGrant(code, state);
+    const { homeserverUrl, tokenResponse, identityServerUrl, oidcClientSettings } =
+        await completeAuthorizationCodeGrant(code, state);
 
     // @TODO(kerrya) do something with the refresh token https://github.com/vector-im/element-web/issues/25444
 
@@ -91,5 +94,7 @@ export const completeOidcLogin = async (
         homeserverUrl: homeserverUrl,
         identityServerUrl: identityServerUrl,
         accessToken: tokenResponse.access_token,
+        clientId: oidcClientSettings.clientId,
+        issuer: oidcClientSettings.issuer,
     };
 };

src/utils/oidc/persistOidcSettings.ts

@@ -0,0 +1,51 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+const clientIdStorageKey = "mx_oidc_client_id";
+const tokenIssuerStorageKey = "mx_oidc_token_issuer";
+
+/**
+ * Persists oidc clientId and issuer in session storage
+ * Only set after successful authentication
+ * @param clientId
+ * @param issuer
+ */
+export const persistOidcAuthenticatedSettings = (clientId: string, issuer: string): void => {
+    sessionStorage.setItem(clientIdStorageKey, clientId);
+    sessionStorage.setItem(tokenIssuerStorageKey, issuer);
+};
+
+/**
+ * Retrieve stored oidc issuer from session storage
+ * When user has token from OIDC issuer, this will be set
+ * @returns issuer or undefined
+ */
+export const getStoredOidcTokenIssuer = (): string | undefined => {
+    return sessionStorage.getItem(tokenIssuerStorageKey) ?? undefined;
+};
+
+/**
+ * Retrieves stored oidc client id from session storage
+ * @returns clientId
+ * @throws when clientId is not found in session storage
+ */
+export const getStoredOidcClientId = (): string => {
+    const clientId = sessionStorage.getItem(clientIdStorageKey);
+    if (!clientId) {
+        throw new Error("Oidc client id not found in storage");
+    }
+    return clientId;
+};