auth-backend: refactor auth0 to use sign-in resolver

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

plugins/auth-backend/src/providers/auth0/provider.ts

@@ -36,7 +36,15 @@ import {
   makeProfileInfo,
   PassportDoneCallback,
 } from '../../lib/passport';
-import { RedirectInfo, AuthProviderFactory } from '../types';
+import {
+  RedirectInfo,
+  AuthProviderFactory,
+  AuthHandler,
+  SignInResolver,
+} from '../types';
+import { CatalogIdentityClient } from '../../lib/catalog';
+import { TokenIssuer } from '../../identity';
+import { Logger } from 'winston';
 
 type PrivateInfo = {
   refreshToken: string;
@@ -44,12 +52,27 @@ type PrivateInfo = {
 
 export type Auth0AuthProviderOptions = OAuthProviderOptions & {
   domain: string;
+  signInResolver?: SignInResolver<OAuthResult>;
+  authHandler: AuthHandler<OAuthResult>;
+  tokenIssuer: TokenIssuer;
+  catalogIdentityClient: CatalogIdentityClient;
+  logger: Logger;
 };
 
 export class Auth0AuthProvider implements OAuthHandlers {
   private readonly _strategy: Auth0Strategy;
+  private readonly signInResolver?: SignInResolver<OAuthResult>;
+  private readonly authHandler: AuthHandler<OAuthResult>;
+  private readonly tokenIssuer: TokenIssuer;
+  private readonly catalogIdentityClient: CatalogIdentityClient;
+  private readonly logger: Logger;
 
   constructor(options: Auth0AuthProviderOptions) {
+    this.signInResolver = options.signInResolver;
+    this.authHandler = options.authHandler;
+    this.tokenIssuer = options.tokenIssuer;
+    this.catalogIdentityClient = options.catalogIdentityClient;
+    this.logger = options.logger;
     this._strategy = new Auth0Strategy(
       {
         clientID: options.clientId,
@@ -98,18 +121,8 @@ export class Auth0AuthProvider implements OAuthHandlers {
       PrivateInfo
     >(req, this._strategy);
 
-    const profile = makeProfileInfo(result.fullProfile, result.params.id_token);
-
     return {
-      response: await this.populateIdentity({
-        profile,
-        providerInfo: {
-          idToken: result.params.id_token,
-          accessToken: result.accessToken,
-          scope: result.params.scope,
-          expiresInSeconds: result.params.expires_in,
-        },
-      }),
+      response: await this.handleResult(result),
       refreshToken: privateInfo.refreshToken,
     };
   }
@@ -125,53 +138,123 @@ export class Auth0AuthProvider implements OAuthHandlers {
       this._strategy,
       accessToken,
     );
-    const profile = makeProfileInfo(fullProfile, params.id_token);
 
-    return this.populateIdentity({
-      providerInfo: {
-        accessToken,
-        idToken: params.id_token,
-        expiresInSeconds: params.expires_in,
-        scope: params.scope,
-      },
-      profile,
+    return this.handleResult({
+      fullProfile,
+      params,
+      accessToken,
+      refreshToken: req.refreshToken,
     });
   }
 
-  // Use this function to grab the user profile info from the token
-  // Then populate the profile with it
-  private async populateIdentity(
-    response: OAuthResponse,
-  ): Promise<OAuthResponse> {
-    const { profile } = response;
+  private async handleResult(result: OAuthResult) {
+    const { profile } = await this.authHandler(result);
 
-    if (!profile.email) {
-      throw new Error('Profile does not contain an email');
+    const response: OAuthResponse = {
+      providerInfo: {
+        idToken: result.params.id_token,
+        accessToken: result.accessToken,
+        scope: result.params.scope,
+        expiresInSeconds: result.params.expires_in,
+      },
+      profile,
+    };
+
+    if (this.signInResolver) {
+      response.backstageIdentity = await this.signInResolver(
+        {
+          result,
+          profile,
+        },
+        {
+          tokenIssuer: this.tokenIssuer,
+          catalogIdentityClient: this.catalogIdentityClient,
+          logger: this.logger,
+        },
+      );
     }
 
-    const id = profile.email.split('@')[0];
-
-    return { ...response, backstageIdentity: { id, token: '' } };
+    return response;
   }
 }
 
-export type Auth0ProviderOptions = {};
+const defaultSignInResolver: SignInResolver<OAuthResult> = async (
+  info,
+  ctx,
+) => {
+  const { profile } = info;
+
+  if (!profile.email) {
+    throw new Error('Profile does not contain an email');
+  }
+
+  const id = profile.email.split('@')[0];
+
+  const token = await ctx.tokenIssuer.issueToken({
+    claims: { sub: id, ent: [`user:default/${id}`] },
+  });
+
+  return { id, token };
+};
+
+export type Auth0ProviderOptions = {
+  /**
+   * The profile transformation function used to verify and convert the auth response
+   * into the profile that will be presented to the user.
+   */
+  authHandler?: AuthHandler<OAuthResult>;
+
+  /**
+   * Configure sign-in for this provider, without it the provider can not be used to sign users in.
+   */
+  signIn?: {
+    /**
+     * Maps an auth result to a Backstage identity for the user.
+     */
+    resolver: SignInResolver<OAuthResult>;
+  };
+};
 
 export const createAuth0Provider = (
-  _options?: Auth0ProviderOptions,
+  options?: Auth0ProviderOptions,
 ): AuthProviderFactory => {
-  return ({ providerId, globalConfig, config, tokenIssuer }) =>
+  return ({
+    providerId,
+    globalConfig,
+    config,
+    tokenIssuer,
+    catalogApi,
+    logger,
+  }) =>
     OAuthEnvironmentHandler.mapConfig(config, envConfig => {
       const clientId = envConfig.getString('clientId');
       const clientSecret = envConfig.getString('clientSecret');
       const domain = envConfig.getString('domain');
       const callbackUrl = `${globalConfig.baseUrl}/${providerId}/handler/frame`;
 
+      const catalogIdentityClient = new CatalogIdentityClient({
+        catalogApi,
+        tokenIssuer,
+      });
+
+      const authHandler: AuthHandler<OAuthResult> = options?.authHandler
+        ? options.authHandler
+        : async ({ fullProfile, params }) => ({
+            profile: makeProfileInfo(fullProfile, params.id_token),
+          });
+
+      const signInResolver = options?.signIn?.resolver ?? defaultSignInResolver;
+
       const provider = new Auth0AuthProvider({
         clientId,
         clientSecret,
         callbackUrl,
         domain,
+        authHandler,
+        signInResolver,
+        tokenIssuer,
+        catalogIdentityClient,
+        logger,
       });
 
       return OAuthAdapter.fromConfig(globalConfig, provider, {

plugins/auth-backend/src/providers/index.ts

@@ -14,6 +14,10 @@
  * limitations under the License.
  */
 
+export * from './atlassian';
+export * from './auth0';
+export * from './aws-alb';
+export * from './bitbucket';
 export * from './github';
 export * from './gitlab';
 export * from './google';
@@ -21,9 +25,6 @@ export * from './microsoft';
 export * from './oauth2';
 export * from './oidc';
 export * from './okta';
-export * from './bitbucket';
-export * from './atlassian';
-export * from './aws-alb';
 export * from './saml';
 
 export { factories as defaultAuthProviderFactories } from './factories';