イベントデータ型チェック

Author: try0

src/channel.ts

@@ -3,6 +3,24 @@ import type { MessageData, Transport } from "./types";
 import { createLogger } from "./log";
 const logger = createLogger();
 
+/**
+ * メッセージデータの型をチェックします。
+ * @param obj チェック対象のオブジェクト
+ * @returns 
+ */
+export function isMessageData(obj: any): obj is MessageData {
+    if (obj === null || obj === undefined) {
+        return false;
+    }
+
+    return (
+        typeof obj === "object" &&
+        typeof obj.type === "string" &&
+        typeof obj.requestId === "string" &&
+        (typeof obj.tabId === "string" || obj.tabId === null)
+    );
+}
+
 /**
  * BroadcastChannel トランスポート実装
  * iOSだとバックグラウンドタブとの通信うまくいかないかも
@@ -23,6 +41,10 @@ export class BroadcastChannelTransport implements Transport {
 
     private handleMessage(event: MessageEvent) {
         if (event.data && typeof event.data === "object" && this.messageCallback) {
+            if (!isMessageData(event.data)) {
+                logger.warn(`Received invalid message data:`, event.data);
+                return;
+            }
             this.messageCallback(event.data as MessageData);
         }
     }
@@ -62,6 +84,10 @@ export class LocalStorageTransport implements Transport {
         if (event.key && event.key.startsWith(`${this.keyPrefix}_`) && event.newValue && this.messageCallback) {
             try {
                 const message = JSON.parse(event.newValue) as MessageData;
+                if (!isMessageData(message)) {
+                    logger.warn(`Received invalid message data:`, message);
+                    return;
+                }
                 this.messageCallback(message);
             } catch (e) {
                 // JSON parse エラーは無視

tests/unit/channel.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeEach, vi } from 'vitest';
-import { LocalStorageTransport, BroadcastChannelTransport, TransportRacer } from '../../src/channel';
+import { LocalStorageTransport, BroadcastChannelTransport, TransportRacer, isMessageData } from '../../src/channel';
 import { MessageData } from '../../src/types';
 
 describe('LocalStorageTransport', () => {
@@ -133,4 +133,59 @@ describe('TransportRacer', () => {
     it('getTransportNamesでトランスポート名が取得できる', () => {
         expect(racer.getTransportNames()).toEqual(['localStorage']);
     });
+});
+
+
+
+describe("isMessageData", () => {
+    it("正しいMessageData型のオブジェクトの場合はtrueを返す", () => {
+        const obj = {
+            type: "test",
+            requestId: "req-1",
+            tabId: "tab-1"
+        };
+        expect(isMessageData(obj)).toBe(true);
+    });
+
+    it("tabIdがnullでもtrueを返す", () => {
+        const obj = {
+            type: "test",
+            requestId: "req-2",
+            tabId: null
+        };
+        expect(isMessageData(obj)).toBe(true);
+    });
+
+    it("typeがstringでない場合はfalseを返す", () => {
+        const obj = {
+            type: 123,
+            requestId: "req-3",
+            tabId: "tab-3"
+        };
+        expect(isMessageData(obj)).toBe(false);
+    });
+
+    it("requestIdがstringでない場合はfalseを返す", () => {
+        const obj = {
+            type: "test",
+            requestId: 456,
+            tabId: "tab-4"
+        };
+        expect(isMessageData(obj)).toBe(false);
+    });
+
+    it("tabIdがstringでもnullでもない場合はfalseを返す", () => {
+        const obj = {
+            type: "test",
+            requestId: "req-5",
+            tabId: 789
+        };
+        expect(isMessageData(obj)).toBe(false);
+    });
+
+    it("オブジェクトでない値の場合はfalseを返す", () => {
+        expect(isMessageData(null)).toBe(false);
+        expect(isMessageData(undefined)).toBe(false);
+        expect(isMessageData("string")).toBe(false);
+    });
 });