[SSF 109]: Email automation spike

apps/backend/src/emails/awsSes.wrapper.ts

@@ -0,0 +1,69 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { SESv2Client, SendEmailCommand } from '@aws-sdk/client-sesv2';
+import MailComposer from 'nodemailer/lib/mail-composer';
+import * as dotenv from 'dotenv';
+import Mail from 'nodemailer/lib/mailer';
+import { AMAZON_SES_CLIENT } from './awsSesClient.factory';
+dotenv.config();
+
+export interface EmailAttachment {
+  filename: string;
+  content: Buffer;
+}
+
+@Injectable()
+export class AmazonSESWrapper {
+  private client: SESv2Client;
+
+  /**
+   * @param client injected from `awsSesClient.factory.ts`
+   * builds our Amazon SES v2 client with credentials from environment variables
+   */
+  constructor(@Inject(AMAZON_SES_CLIENT) client: SESv2Client) {
+    this.client = client;
+  }
+
+  /**
+   * Sends an email via Amazon SES.
+   *
+   * @param recipientEmails the email addresses of the recipients
+   * @param subject the subject of the email
+   * @param bodyHtml the HTML body of the email
+   * @param attachments any attachments to include in the email
+   * @resolves if the email was sent successfully
+   * @rejects if the email was not sent successfully
+   */
+  async sendEmails(
+    recipientEmails: string[],
+    subject: string,
+    bodyHtml: string,
+    attachments?: EmailAttachment[],
+  ) {
+    const mailOptions: Mail.Options = {
+      from: process.env.AWS_SES_SENDER_EMAIL,
+      to: recipientEmails,
+      subject: subject,
+      html: bodyHtml,
+    };
+
+    if (attachments) {
+      mailOptions.attachments = attachments.map((a) => ({
+        filename: a.filename,
+        content: a.content,
+        encoding: 'base64',
+      }));
+    }
+
+    const messageData = await new MailComposer(mailOptions).compile().build();
+
+    const command = new SendEmailCommand({
+      Content: {
+        Raw: {
+          Data: messageData,
+        },
+      },
+    });
+
+    return await this.client.send(command);
+  }
+}

apps/backend/src/emails/awsSesClient.factory.ts

@@ -0,0 +1,28 @@
+import { Provider } from '@nestjs/common';
+import { SESv2Client } from '@aws-sdk/client-sesv2';
+import { assert } from 'console';
+import * as dotenv from 'dotenv';
+dotenv.config();
+
+export const AMAZON_SES_CLIENT = 'AMAZON_SES_CLIENT';
+
+/**
+ * Factory that produces a new instance of the Amazon SES v2 client.
+ * Used to send emails via Amazon SES and actually set it up with credentials.
+ */
+export const AmazonSESClientFactory: Provider<SESv2Client> = {
+  provide: AMAZON_SES_CLIENT,
+  useFactory: () => {
+    assert(
+      process.env.AWS_ACCESS_KEY_ID !== undefined,
+      'AWS_ACCESS_KEY_ID is not defined',
+    );
+    assert(
+      process.env.AWS_SECRET_ACCESS_KEY !== undefined,
+      'AWS_SECRET_ACCESS_KEY is not defined',
+    );
+    assert(process.env.AWS_REGION !== undefined, 'AWS_REGION is not defined');
+
+    return new SESv2Client({ region: process.env.AWS_REGION });
+  },
+};

apps/backend/src/emails/email.module.ts

@@ -0,0 +1,10 @@
+import { Module } from '@nestjs/common';
+import { EmailsService } from './email.service';
+import { AmazonSESWrapper } from './awsSes.wrapper';
+import { AmazonSESClientFactory } from './awsSesClient.factory';
+
+@Module({
+  providers: [AmazonSESWrapper, AmazonSESClientFactory, EmailsService],
+  exports: [EmailsService],
+})
+export class EmailsModule {}

apps/backend/src/emails/email.service.ts

@@ -0,0 +1,41 @@
+import { Injectable, Logger } from '@nestjs/common';
+import Bottleneck from 'bottleneck';
+import { AmazonSESWrapper, EmailAttachment } from './awsSes.wrapper';
+
+@Injectable()
+export class EmailsService {
+  private readonly EMAILS_SENT_PER_SECOND = 14;
+  private readonly logger = new Logger(EmailsService.name);
+  private readonly limiter: Bottleneck;
+
+  constructor(private amazonSESWrapper: AmazonSESWrapper) {
+    this.limiter = new Bottleneck({
+      minTime: Math.ceil(1000 / this.EMAILS_SENT_PER_SECOND),
+      maxConcurrent: 1,
+    });
+  }
+
+  /**
+   * Sends an email.
+   *
+   * @param recipientEmail the email address of the recipients
+   * @param subject the subject of the email
+   * @param bodyHtml the HTML body of the email
+   * @param attachments any base64 encoded attachments to inlude in the email
+   * @resolves if the email was sent successfully
+   * @rejects if the email was not sent successfully
+   */
+  public async sendEmails(
+    recipientEmails: string[],
+    subject: string,
+    bodyHTML: string,
+    attachments?: EmailAttachment[],
+  ): Promise<unknown> {
+    return this.amazonSESWrapper.sendEmails(
+      recipientEmails,
+      subject,
+      bodyHTML,
+      attachments,
+    );
+  }
+}

apps/backend/src/emails/types.ts

@@ -0,0 +1,29 @@
+import {
+  IsString,
+  IsOptional,
+  IsNotEmpty,
+  MaxLength,
+  IsEmail,
+  IsArray,
+} from 'class-validator';
+import { EmailAttachment } from './awsSes.wrapper';
+
+export class SendEmailDTO {
+  @IsArray()
+  @IsEmail({}, { each: true })
+  @MaxLength(255, { each: true })
+  toEmails!: string[];
+
+  @IsString()
+  @IsNotEmpty()
+  @MaxLength(255)
+  subject!: string;
+
+  @IsString()
+  @IsNotEmpty()
+  bodyHtml!: string;
+
+  @IsArray()
+  @IsOptional()
+  attachments?: EmailAttachment[];
+}

apps/backend/src/pantries/pantries.controller.spec.ts

@@ -14,10 +14,12 @@ import {
   ReserveFoodForAllergic,
   ServeAllergicChildren,
 } from './types';
+import { EmailsService } from '../emails/email.service';
 import { ApplicationStatus } from '../shared/types';
 
 const mockPantriesService = mock<PantriesService>();
 const mockOrdersService = mock<OrdersService>();
+const mockEmailsService = mock<EmailsService>();
 
 describe('PantriesController', () => {
   let controller: PantriesController;
@@ -84,6 +86,10 @@ describe('PantriesController', () => {
           provide: OrdersService,
           useValue: mockOrdersService,
         },
+        {
+          provide: EmailsService,
+          useValue: mockEmailsService,
+        },
       ],
     }).compile();
 

apps/backend/src/pantries/pantries.controller.ts

@@ -24,13 +24,16 @@ import {
 } from './types';
 import { Order } from '../orders/order.entity';
 import { OrdersService } from '../orders/order.service';
+import { EmailsService } from '../emails/email.service';
+import { SendEmailDTO } from '../emails/types';
 import { Public } from '../auth/public.decorator';
 
 @Controller('pantries')
 export class PantriesController {
   constructor(
     private pantriesService: PantriesService,
     private ordersService: OrdersService,
+    private emailsService: EmailsService,
   ) {}
 
   @Roles(Role.ADMIN)
@@ -314,4 +317,16 @@ export class PantriesController {
   ): Promise<void> {
     return this.pantriesService.deny(pantryId);
   }
+
+  @Post('/email')
+  async sendEmail(@Body() sendEmailDTO: SendEmailDTO): Promise<void> {
+    const { toEmails, subject, bodyHtml, attachments } = sendEmailDTO;
+
+    await this.emailsService.sendEmails(
+      toEmails,
+      subject,
+      bodyHtml,
+      attachments,
+    );
+  }
 }

apps/backend/src/pantries/pantries.module.ts

@@ -5,12 +5,14 @@ import { PantriesController } from './pantries.controller';
 import { Pantry } from './pantries.entity';
 import { AuthModule } from '../auth/auth.module';
 import { OrdersModule } from '../orders/order.module';
+import { EmailsModule } from '../emails/email.module';
 import { User } from '../users/user.entity';
 
 @Module({
   imports: [
     TypeOrmModule.forFeature([Pantry, User]),
     OrdersModule,
+    EmailsModule,
     forwardRef(() => AuthModule),
   ],
   controllers: [PantriesController],

package.json

@@ -20,6 +20,7 @@
     "@aws-amplify/ui-react": "^6.9.3",
     "@aws-sdk/client-cognito-identity-provider": "^3.410.0",
     "@aws-sdk/client-s3": "^3.735.0",
+    "@aws-sdk/client-sesv2": "^3.989.0",
     "@aws-sdk/lib-storage": "^3.735.0",
     "@chakra-ui/icons": "^2.2.4",
     "@chakra-ui/react": "^3.27.0",
@@ -38,6 +39,7 @@
     "amazon-cognito-identity-js": "^6.3.5",
     "aws-amplify": "^6.15.10",
     "axios": "^1.8.2",
+    "bottleneck": "^2.19.5",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.14.0",
     "dotenv": "^16.4.5",
@@ -47,6 +49,7 @@
     "lucide-react": "^0.544.0",
     "mongodb": "^6.1.0",
     "multer": "^2.0.2",
+    "nodemailer": "^8.0.1",
     "passport": "^0.6.0",
     "passport-jwt": "^4.0.1",
     "pg": "^8.12.0",
@@ -63,7 +66,6 @@
     "@jest/globals": "^30.1.2",
     "@nestjs/schematics": "^10.0.2",
     "@nestjs/testing": "^10.0.2",
-    "@nx/cypress": "16.10.0",
     "@nx/eslint-plugin": "16.10.0",
     "@nx/eslint-plugin-nx": "^16.0.0-beta.1",
     "@nx/jest": "16.10.0",
@@ -75,13 +77,14 @@
     "@types/jest": "^29.4.0",
     "@types/multer": "^1.4.12",
     "@types/node": "^18.14.2",
+    "@types/nodemailer": "^6.4.17",
     "@types/react": "^18.2.14",
     "@types/react-dom": "^18.2.6",
     "@typescript-eslint/eslint-plugin": "^8.23.0",
     "@typescript-eslint/parser": "^8.23.0",
     "@vitejs/plugin-react": "^4.0.0",
     "@vitest/ui": "^0.32.0",
-    "cypress": "^13.0.0",
+    "ansi-regex": "5.0.1",
     "eslint": "^8.46.0",
     "eslint-config-prettier": "^8.1.0",
     "eslint-plugin-cypress": "^2.13.4",
@@ -97,6 +100,8 @@
     "nx": "16.10.0",
     "nx-cloud": "^19.1.0",
     "prettier": "^2.6.2",
+    "string-width": "4.2.3",
+    "strip-ansi": "6.0.1",
     "ts-jest": "^29.1.0",
     "ts-node": "^10.9.2",
     "tsconfig-paths": "^4.2.0",
@@ -115,8 +120,6 @@
     "semver": "^7.5.2",
     "tmp": "^0.2.4",
     "webpack-dev-server": "^5.2.1",
-    "vite": "^5.4.21",
-    "strip-ansi": "6.0.1",
-    "string-width": "4.2.3"
+    "vite": "^5.4.21"
   }
-} 
+}