add count on redirects to mitigate very unlikely DOS (microsoft#58)

malakumar85 · Jul 25, 2023 · 54e3473 · 54e3473
1 parent 795fe54
commit 54e3473
Showing 1 changed file with 82 additions and 74 deletions.
diff --git a/examples/music/src/authz.ts b/examples/music/src/authz.ts
@@ -12,92 +12,100 @@ type AuthzHandler = AuthzHandlerFn | undefined;
 type AuthzServer = Server | undefined;
 
 const scope = [
-  "user-read-private",
-  "playlist-read-collaborative",
-  "playlist-modify-private",
-  "playlist-read-private",
-  "playlist-modify-public",
-  "streaming",
-  "user-library-read",
-  "user-top-read",
-  "user-read-playback-state",
-  "user-modify-playback-state",
-  "user-read-recently-played",
-  "user-read-currently-playing",
-  "user-library-modify",
-  "ugc-image-upload",
+    "user-read-private",
+    "playlist-read-collaborative",
+    "playlist-modify-private",
+    "playlist-read-private",
+    "playlist-modify-public",
+    "streaming",
+    "user-library-read",
+    "user-top-read",
+    "user-read-playback-state",
+    "user-modify-playback-state",
+    "user-read-recently-played",
+    "user-read-currently-playing",
+    "user-library-modify",
+    "ugc-image-upload",
 ].join("%20");
 
 const baseClientId = process.env.SPOTIFY_APP_CLI;
 const defaultPort = process.env.SPOTIFY_APP_PORT;
 export class Authzor {
-  url: string;
-  app: express.Express;
-  handler: AuthzHandler;
-  server: AuthzServer;
+    url: string;
+    app: express.Express;
+    handler: AuthzHandler;
+    server: AuthzServer;
+    private redirectCount = 0;
 
-  constructor(
-    public port = defaultPort,
-    public showDialog = false,
-    public clientId = baseClientId
-  ) {
-    const redirectUri = "http://localhost:" + port + "/callback";
+    constructor(
+        public port = defaultPort,
+        public showDialog = false,
+        public clientId = baseClientId
+    ) {
+        const redirectUri = "http://localhost:" + port + "/callback";
 
-    this.url =
-      "https://accounts.spotify.com/authorize" +
-      "?client_id=" +
-      clientId +
-      "&response_type=token" +
-      "&scope=" +
-      scope +
-      "&show_dialog=" +
-      showDialog +
-      "&redirect_uri=" +
-      redirectUri;
+        this.url =
+            "https://accounts.spotify.com/authorize" +
+            "?client_id=" +
+            clientId +
+            "&response_type=token" +
+            "&scope=" +
+            scope +
+            "&show_dialog=" +
+            showDialog +
+            "&redirect_uri=" +
+            redirectUri;
 
-    this.app = express();
+        this.app = express();
 
-    this.app.get("/callback", (req, res) => {
-      res.sendFile(__dirname + "/callback.html");
-      if (req.query.error) {
-        console.log(
-          chalk.red("Something went wrong. Error: "),
-          req.query.error
-        );
-      }
-    });
+        this.app.get("/callback", (req, res) => {
+            if (req.query.error) {
+                console.log(
+                    chalk.red("Something went wrong. Error: "),
+                    req.query.error
+                );
+            } else {
+                // update this when implementing re-auth on token expire
+                if (this.redirectCount === 0) {
+                    res.sendFile(__dirname + "/callback.html");
+                    this.redirectCount++;
+                }
+            }
+        });
 
-    this.app.get("/token", (req, res) => {
-      res.sendStatus(200);
-      const token = req.query.access_token as string;
-      if (token) {
-        if (this.handler) {
-          this.handler(token);
-        }
-      }
-      this.close();
-    });
-  }
+        this.app.get("/token", (req, res) => {
+            res.sendStatus(200);
+            const token = req.query.access_token as string;
+            if (token) {
+                if (this.handler) {
+                    this.handler(token);
+                }
+            }
+            this.close();
+        });
+    }
 
-  authorize(connect: boolean, handler: AuthzHandlerFn) {
-    if (baseClientId && connect) {
-      this.handler = handler;
-      this.server = this.app.listen(this.port, () => {
-        if (this.showDialog) {
-          console.log(
-            chalk.blue("Opening the Spotify Login Dialog in your browser...")
-          );
+    authorize(connect: boolean, handler: AuthzHandlerFn) {
+        if (baseClientId && connect) {
+            this.handler = handler;
+            this.server = this.app.listen(this.port, () => {
+                if (this.showDialog) {
+                    console.log(
+                        chalk.blue(
+                            "Opening the Spotify Login Dialog in your browser..."
+                        )
+                    );
+                }
+                open(this.url, { wait: false });
+            });
+        } else {
+            handler(undefined);
         }
-        open(this.url, { wait: false });
-      });
-    } else {
-      handler(undefined);
     }
-  }
-
-  close() {
-    if (this.server) {
-      this.server.close();
+
+    close() {
+        if (this.server) {
+            this.server.close();
+        }
     }
-  }
 }