Google Chat Bot を Cloud Functions + Python + uv で最小構成で作ってみた

brew install --cask google-cloud-sdk

# CLI 認証（ブラウザが開きます）
gcloud auth login

# Application Default Credentials（ADC）の設定
gcloud auth application-default login

WARNING:
Cannot find a quota project to add to ADC. You might receive a "quota exceeded" or "API not enabled" error.

gcloud auth application-default set-quota-project YOUR_PROJECT_ID

# デフォルトプロジェクトの設定
gcloud config set project YOUR_PROJECT_ID

# 必要な API の有効化
gcloud services enable cloudfunctions.googleapis.com \
  cloudbuild.googleapis.com \
  chat.googleapis.com \
  run.googleapis.com

# 新しい configuration を作成
gcloud config configurations create my-other-project
gcloud config set project other-project-id
gcloud auth login

# configuration の一覧
gcloud config configurations list

# 切り替え
gcloud config configurations activate my-other-project

# ADC の quota project を切り替え
gcloud auth application-default set-quota-project other-project-id

google-chat-bot/
├── main.py              # Cloud Function エントリーポイント
├── pyproject.toml       # uv 管理の依存関係
├── uv.lock              # uv ロックファイル
├── .python-version      # Python バージョン
└── .gitignore

# uv でプロジェクト初期化
uv init --no-readme
rm hello.py  # 自動生成されるファイルを削除

# 依存関係の追加
uv add functions-framework
uv add --dev pytest

import json
import sys

import functions_framework
from flask import jsonify

def create_message(text):
    """Google Workspace Add-ons のレスポンス形式でテキストをラップする"""
    return {
        "hostAppDataAction": {
            "chatDataAction": {
                "createMessageAction": {
                    "message": {
                        "text": text,
                    }
                }
            }
        }
    }

@functions_framework.http
def handle_chat(request):
    """Google Chat ボットのエントリーポイント"""
    body = request.get_json(silent=True)

    if not body:
        return jsonify(create_message("Empty request"))

    chat = body.get("chat", {})
    message_payload = chat.get("messagePayload", {})
    message = message_payload.get("message", {})
    user_text = message.get("text", "")
    sender = message.get("sender", {}).get("displayName", "someone")

    return jsonify(create_message(f"Hello {sender}! You said: {user_text}"))

uv run functions-framework --target=handle_chat --port=8080

curl -X POST http://localhost:8080 \
  -H "Content-Type: application/json" \
  -d '{"chat": {"messagePayload": {"message": {"text": "hello", "sender": {"displayName": "Test User"}}}}}'

gcloud functions deploy google-chat-bot \
  --gen2 \
  --runtime=python314 \
  --region=asia-northeast1 \
  --source=. \
  --entry-point=handle_chat \
  --trigger-http \
  --allow-unauthenticated

https://asia-northeast1-YOUR_PROJECT_ID.cloudfunctions.net/google-chat-bot

https://asia-northeast1-YOUR_PROJECT_ID.cloudfunctions.net/google-chat-bot

# 認証付きでリデプロイ
gcloud functions deploy google-chat-bot \
  --gen2 \
  --runtime=python314 \
  --region=asia-northeast1 \
  --source=. \
  --entry-point=handle_chat \
  --trigger-http \
  --no-allow-unauthenticated

# Google Chat のサービスアカウントに invoker 権限を付与
gcloud run services add-iam-policy-binding google-chat-bot \
  --region=asia-northeast1 \
  --member="serviceAccount:chat@system.gserviceaccount.com" \
  --role="roles/run.invoker"

{
  "type": "MESSAGE",
  "message": {
    "text": "hello",
    "sender": {"displayName": "User"}
  }
}

{
  "commonEventObject": { ... },
  "authorizationEventObject": { ... },
  "chat": {
    "messagePayload": {
      "message": {
        "text": "こんにちは",
        "sender": {"displayName": "林昱辰"}
      }
    }
  }
}

{"text": "Hello!"}

{
  "hostAppDataAction": {
    "chatDataAction": {
      "createMessageAction": {
        "message": {
          "text": "Hello!"
        }
      }
    }
  }
}

print(f"REQUEST BODY: {json.dumps(body, ensure_ascii=False)}", file=sys.stderr, flush=True)

gcloud logging read \
  'resource.type="cloud_run_revision" AND resource.labels.service_name="google-chat-bot"' \
  --limit=10 \
  --format="table(timestamp,severity,textPayload)" \
  --project=YOUR_PROJECT_ID