Cloudflare Workers環境で「Illegal invocation」エラーが起きたときに試したこと

// MCPツールとしてNotion検索機能を提供
const searchResult = await searchSites(apiKey, databaseId, "検索クエリ");

import { Client } from '@notionhq/client';
 
export async function searchSites(
  apiKey: string,
  databaseId: string,
  query: string,
): Promise<NotionResponse[]> {
  const client = new Client({ auth: apiKey });
  
  const response = await client.databases.query({
    database_id: databaseId,
    filter: {
      or: [
        {
          property: 'title',
          rich_text: { contains: query },
        },
        {
          property: 'description',
          rich_text: { contains: query },
        },
      ],
    },
  });
  
  return response.results;
}

import { McpAgent } from 'agents/mcp';
import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { z } from 'zod';
import {
  searchSites,
  extractSiteName,
  extractDescription,
} from './services/notion';
 
export class MyMCP extends McpAgent<Env> {
  server = new McpServer({
    name: 'Notion Search MCP Server',
    version: '1.0.0',
  });
 
  async init() {
    this.server.tool(
      'site_search',
      'Notionデータベースからサイト名やキーワードで検索します',
      {
        query: z.string().describe('検索したいサイト名やキーワード'),
      },
      async ({ query }) => {
        const notionApiKey = this.env.NOTION_API_KEY;
        const databaseId = this.env.NOTION_DATABASE_ID;
        const sites = await searchSites(notionApiKey, databaseId, query);
 
        if (sites.length === 0) {
          return {
            content: [
              {
                type: 'text',
                text: `「${query}」に関連するサイトが見つかりませんでした。`,
              },
            ],
          };
        }
 
        const results = sites.map((site) => ({
          name: extractSiteName(site),
          description: extractDescription(site),
        }));
 
        const resultText = results
          .map(
            (result) =>
              `**${result.name}**\n` + `説明: ${result.description}\n`,
          )
          .join('\n---\n');
 
        return {
          content: [
            {
              type: 'text',
              text: `${sites.length}件のサイトが見つかりました:\n\n${resultText}`,
            },
          ],
        };
      },
    );
  }
}
 

TypeError: Illegal invocation: function called with incorrect 'this' reference

curl -X POST https://api.notion.com/v1/databases/databaseid/query \
  -H "Authorization: Bearer $NOTION_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Notion-Version: 2022-06-28" \
  -d '{
    "filter": {
      "or": [
        {
          "property": "title",
          "rich_text": { "contains": "LINE" }
        }
      ]
    }
  }'

export async function searchSites(
  apiKey: string,
  databaseId: string,
  query: string,
): Promise<NotionResponse[]> {
  console.log('=== Notion API デバッグ情報 ===');
  console.log(`APIキー: ${apiKey ? `${apiKey.substring(0, 10)}...` : '未定義'}`);
  console.log(`データベースID: ${databaseId}`);
  console.log(`検索クエリ: "${query}"`);
 
  try {
    console.log('--- ステップ1: Notionクライアント初期化 ---');
    const client = new Client({ auth: apiKey });
    console.log('Notionクライアント初期化成功');
 
    console.log('--- ステップ2: データベースオブジェクトの確認 ---');
    console.log('client.databases:', typeof client.databases);
    console.log('client.databases.query:', typeof client.databases.query);
 
    console.log('--- ステップ3: クエリ実行 ---');
    const response = await client.databases.query(queryParams);
    
    return response.results;
  } catch (error) {
    console.error('Notion APIエラー:', error);
    return [];
  }
}

✘ [ERROR] Notion APIエラー: TypeError: Illegal invocation: function called with incorrect `this` reference. See https://developers.cloudflare.com/workers/observability/errors/#illegal-invocation-errors for details.

const supabase = createClient('https://xyzcompany.supabase.co', 'public-anon-key', { 
  fetch: fetch.bind(globalThis) 
})

export async function searchSites(
  apiKey: string,
  databaseId: string,
  query: string,
): Promise<NotionResponse[]> {
  try {
    // fetch.bind(globalThis)でthisコンテキストを明示的に設定
    const client = new Client({ 
      auth: apiKey,
      fetch: fetch.bind(globalThis)
    });
 
    const response = await client.databases.query({
      database_id: databaseId,
      filter: {
        or: [
          {
            property: 'title',
            rich_text: { contains: query },
          },
          {
            property: 'description',
            rich_text: { contains: query },
          },
        ],
      },
    });
 
    return response.results;
  } catch (error) {
    console.error('Notion APIエラー:', error);
    return [];
  }
}

fetch: fetch.bind(globalThis)