Forgot the add the file

Author: Perlkonig

api/sockets/authHandler.ts

@@ -0,0 +1,87 @@
+import { ApiGatewayManagementApiClient, DeleteConnectionCommand } from "@aws-sdk/client-apigatewaymanagementapi";
+import { CognitoJwtVerifier } from "aws-jwt-verify";
+import { APIGatewayProxyEventV2 } from "aws-lambda";
+import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
+import { DynamoDBDocumentClient, PutCommand } from '@aws-sdk/lib-dynamodb';
+
+type WebSocketRequestContext = APIGatewayProxyEventV2["requestContext"] & {
+  connectionId: string;
+  routeKey: string;
+  eventType: "CONNECT" | "MESSAGE" | "DISCONNECT";
+};
+
+interface WebSocketEvent extends Omit<APIGatewayProxyEventV2, "requestContext"> {
+  requestContext: WebSocketRequestContext;
+}
+
+const REGION = "us-east-1";
+const clnt = new DynamoDBClient({ region: REGION });
+const marshallOptions = {
+  // Whether to automatically convert empty strings, blobs, and sets to `null`.
+  convertEmptyValues: false, // false, by default.
+  // Whether to remove undefined values while marshalling.
+  removeUndefinedValues: true, // false, by default.
+  // Whether to convert typeof object to map attribute.
+  convertClassInstanceToMap: false, // false, by default.
+};
+const unmarshallOptions = {
+  // Whether to return numbers as a string instead of converting them to native JavaScript numbers.
+  wrapNumbers: false, // false, by default.
+};
+const translateConfig = { marshallOptions, unmarshallOptions };
+const ddbDocClient = DynamoDBDocumentClient.from(clnt, translateConfig);
+
+const verifier = CognitoJwtVerifier.create({
+  userPoolId: process.env.userpoolId!,
+  tokenUse: "id",
+  clientId: process.env.userpoolClient!,
+});
+
+export const wsAuthorizer = async (event: WebSocketEvent) => {
+
+   // Parse the incoming message body
+    const body = JSON.parse(event.body ?? "{}");
+    const token: string | undefined = body.token;
+
+  if (!token) {
+     console.error("Missing token in auth message");
+      return { statusCode: 400, body: "Missing token" };
+  }
+
+  try {
+    console.log(`Verifying JWT: ${token}`);
+    const payload = await verifier.verify(token);
+    console.log(`Validated: ${JSON.stringify(payload)}`);
+    const { connectionId } = event.requestContext;
+
+    const userId = payload.sub;
+
+    await ddbDocClient.send(
+        new PutCommand({
+            TableName: process.env.ABSTRACT_PLAY_TABLE!,
+            Item: {
+                pk: "wsConnections",
+                sk: connectionId,
+
+                connectionId,
+                userId,
+
+                // Optional TTL for auto-cleanup
+                ttl: Math.floor(Date.now() / 1000) + 3600,
+            },
+        })
+    );
+  } catch (ex) {
+    console.log("Connect error:", JSON.stringify(ex));
+    const domain = event.requestContext.domainName;
+    const stage = event.requestContext.stage;
+    const connectionId = event.requestContext.connectionId;
+
+    const mgmt = new ApiGatewayManagementApiClient({
+      endpoint: `https://${domain}/${stage}`,
+    });
+
+    await mgmt.send(new DeleteConnectionCommand({ ConnectionId: connectionId }));
+    return { statusCode: 401 };
+  }
+};