【Express.js】AWS SESを使用した自動返信メール機能の実装手順

$ npm install @aws-sdk/client-ses

"@aws-sdk/client-ses": "^3.577.0",
"dotenv": "^16.4.5",
"express": "^4.19.2",
"mongoose": "^8.3.2",

import mongoose, { Document } from "mongoose";

export interface IContact extends Document {
  name: string;
  email: string;
  detail: string;
}

const contactSchema = new mongoose.Schema(
  {
    name: {
      type: String,
      required: true,
    },
    email: {
      type: String,
      required: true,
    },
    detail: {
      type: String,
      required: true,
    },
  },
  {
    timestamps: true,
  }
);

const Contact = mongoose.model<IContact>(
  "Contact",
  contactSchema,
  // 第三引数にMongoDBのコレクション名を指定
  "contacts"
);

export default Contact;

import express from "express";
import {
  createContact,
} from "../controllers/ContactController";

const router = express.Router();

router.post("/create", createContact);

export default router;

import contactRouter from "./routes/contact";

// ...省略

// ルートを設定
app.use("/api/contact", contactRouter);

AWS_ACCESS_KEY_ID=xxx
AWS_SECRET_ACCESS_KEY=xxx
AWS_REGION=ap-northeast-1
SES_VERIFIED_EMAIL=xxx@gmail.com
ADMIN_EMAIL=xxx@gmail.com

import { SESClient, SendEmailCommand } from "@aws-sdk/client-ses";
import dotenv from "dotenv";

dotenv.config();

class AWSSESConfig {
  private static instance: AWSSESConfig;
  private sesClient: SESClient;

  private constructor() {
    // SESクライアントの初期化
    this.sesClient = new SESClient({
      region: "ap-northeast-1",
      credentials: {
        accessKeyId: process.env.AWS_ACCESS_KEY_ID!,
        secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY!,
      },
    });
  }

  public static getInstance(): AWSSESConfig {
    if (!AWSSESConfig.instance) {
      AWSSESConfig.instance = new AWSSESConfig();
    }
    return AWSSESConfig.instance;
  }

  /**
   * メール送信
   * @param to 宛先
   * @param subject 件名
   * @param body string
   * @see https://docs.aws.amazon.com/ja_jp/sdk-for-javascript/v3/developer-guide/javascript_ses_code_examples.html#:r3l:-trigger
   */
  public async sendEmail(to: string, subject: string, body: string) {
    const params = {
      Destination: {
        ToAddresses: [to], // 送信先メールアドレス
      },
      Message: {
        Body: {
          Text: { Data: body }, // メール本文
        },
        Subject: { Data: subject }, // メール件名
      },
      Source: process.env.SES_VERIFIED_EMAIL!, // 検証済み送信元メールアドレス
    };

    try {
      const command = new SendEmailCommand(params);
      // メール送信実行
      const response = await this.sesClient.send(command);
      return response;
    } catch (error) {
      console.error("Error sending email: ", error);
      throw error;
    }
  }
}

export default AWSSESConfig.getInstance();

import { NextFunction, Request, Response } from "express";
import Contact from "../model/Contact";
import AWSSESConfig from "../config/aws/ses";

// 一覧取得
export const getContactList = async (
  req: Request,
  res: Response,
  next: NextFunction
) => {
  try {
    const results = await Contact.find();
    res.json(results);
  } catch (error) {
    next(error);
  }
};

// 新規作成
export const createContact = async (
  req: Request,
  res: Response,
  next: NextFunction
) => {
  const { name, email, detail } = req.body;

  // MongoDBのトランザクションを開始
  const session = await mongoose.startSession();
  session.startTransaction();

  try {
    // 問い合わせデータの保存
    const contactModel = new Contact({ name, email, detail });
    await contactModel.save({ session });

    // ユーザーへの自動返信メール
    const userSubject = "お問い合わせありがとうございます【テック教育ナビ】";
    const userBody = `${name} 様,\n\nお問い合わせいただきありがとうございます。\n\n内容を確認し、後ほどご連絡いたします。\n\nお問い合わせ内容:\n${detail}\n\nよろしくお願いします。`;

    // 管理者への通知メール
    const adminSubject = "新しいお問い合わせ";
    const adminBody = `新しいお問い合わせがありました:\n\n名前: ${name}\nメールアドレス: ${email}\nメッセージ:\n${detail}`;

    // ユーザーへの返信メール送信
    await AWSSESConfig.sendEmail(email, userSubject, userBody);
    // 管理者への通知メール送信
    await AWSSESConfig.sendEmail(
      process.env.ADMIN_EMAIL!,
      adminSubject,
      adminBody
    );

    // トランザクションをコミットしてセッションを終了する
    await session.commitTransaction();
    session.endSession();

    res.status(201).send(contactModel);
  } catch (error) {
    // 処理に失敗した場合は、セッションを破棄してデータの保存を行わない
    await session.abortTransaction();
    session.endSession();
    next(error);
  }
};

// 物理削除
// path: /contact/delete/:id
export const deleteContact = async (
  req: Request,
  res: Response,
  next: NextFunction
) => {
  try {
    const { id } = req.params;
    const result = await Contact.findByIdAndDelete(id);
    if (!result) {
      return res
        .status(404)
        .json({ message: "Delete failed!! Contact not found" });
    }
    return res.status(204).json({ message: `Deleted contact id:${id}` });
  } catch (error) {
    next(error);
  }
};