feat: ms graph api mail service

apps/backend/package.json

@@ -36,6 +36,7 @@
     "@apollo/server": "^5.5.0",
     "@apollo/subgraph": "^2.13.2",
     "@as-integrations/express4": "^1.1.2",
+    "@azure/msal-node": "^5.2.0",
     "@graphql-tools/utils": "^10.1.0",
     "@isaacs/ttlcache": "^1.4.1",
     "@opentelemetry/exporter-logs-otlp-http": "^0.216.0",

apps/backend/src/config/dependencyConfigELI.ts

@@ -48,7 +48,7 @@ import PostgresVisitRegistrationClaimDataSource from '../datasources/postgres/Vi
 import PostgresWorkflowDataSource from '../datasources/postgres/WorkflowDataSource';
 import { eliEmailHandler } from '../eventHandlers/email/eliEmailHandler';
 import createLoggingHandler from '../eventHandlers/logging';
-import { SMTPMailService } from '../eventHandlers/MailService/SMTP/SMTPMailService';
+import { MSGraphMailService } from '../eventHandlers/MailService/MSGraph/MSGraphMailService';
 import {
   createListenToRabbitMQHandler,
   createPostToRabbitMQHandler,
@@ -127,7 +127,7 @@ mapClass(Tokens.DataAccessUsersAuthorization, DataAccessUsersAuthorization);
 
 mapClass(Tokens.AssetRegistrar, EAMAssetRegistrar);
 
-mapClass(Tokens.MailService, SMTPMailService);
+mapClass(Tokens.MailService, MSGraphMailService);
 
 mapValue(Tokens.FapDataColumns, FapDataColumns);
 mapValue(Tokens.FapDataRow, getDataRow);

apps/backend/src/eventHandlers/MailService/MSGraph/MSGraphMailService.ts

@@ -0,0 +1,196 @@
+import { existsSync, readFileSync } from 'node:fs';
+
+import * as msal from '@azure/msal-node';
+import { logger } from '@user-office-software/duo-logger';
+import { NodeMailerTransportOptions } from 'email-templates';
+import * as nodemailer from 'nodemailer';
+import { SentMessageInfo, Transport } from 'nodemailer';
+import MailMessage from 'nodemailer/lib/mailer/mail-message';
+
+import { TemplateMailService } from '../TemplateMailService';
+
+class MSGraphTransport implements Transport<SentMessageInfo> {
+  name: string;
+  version: string;
+
+  private apiUrl: string;
+  private authToken: msal.AuthenticationResult | null = null;
+  private msalClient: msal.ConfidentialClientApplication;
+  private tokenPromise: Promise<any> | null = null;
+
+  constructor() {
+    this.name = 'MSGraphTransport';
+    this.version = '1.0.0';
+    this.apiUrl = process.env.MS_GRAPH_API_URL || '';
+
+    this.msalClient = new msal.ConfidentialClientApplication({
+      auth: {
+        clientId: process.env.MS_GRAPH_API_CLIENT_ID!,
+        clientSecret: process.env.MS_GRAPH_API_CLIENT_SECRET!,
+        authority: `${process.env.MS_GRAPH_API_AUTHORITY}/${process.env.MS_GRAPH_API_TENANT_ID}`,
+      },
+    });
+  }
+
+  protected isTokenExpired(): boolean {
+    if (!this.authToken?.expiresOn) {
+      throw new Error('Invalid token: Missing expiresOn property');
+    }
+
+    return Date.now() >= this.authToken.expiresOn.getTime();
+  }
+
+  private async getAuthToken(): Promise<msal.AuthenticationResult> {
+    // if we already have a valid token, return it
+    if (this.authToken && !this.isTokenExpired()) {
+      return this.authToken;
+    }
+
+    // cache the promise to prevent multiple simultaneous token requests
+    if (!this.tokenPromise) {
+      this.tokenPromise = (async () => {
+        try {
+          this.authToken = await this.msalClient.acquireTokenByClientCredential(
+            {
+              scopes: [`${this.apiUrl}/.default`],
+            }
+          );
+
+          logger.logInfo('Acquired new access token for Microsoft Graph API', {
+            expiresOn: this.authToken?.expiresOn,
+          });
+        } finally {
+          this.tokenPromise = null;
+        }
+      })();
+    }
+
+    return this.tokenPromise;
+  }
+
+  public async send(
+    message: MailMessage<SentMessageInfo>,
+    callback: (err: Error | null, info: unknown) => void
+  ) {
+    try {
+      const token = await this.getAuthToken();
+
+      if (!token?.accessToken) {
+        throw new Error(
+          'Failed to acquire access token for Microsoft Graph API'
+        );
+      }
+
+      const {
+        subject,
+        to,
+        from,
+        html,
+        bcc,
+        attachments = [],
+      } = message.data || {};
+
+      const payload = {
+        message: {
+          subject: subject || '',
+          body: {
+            contentType: 'HTML',
+            content: html || '',
+          },
+          toRecipients: [
+            {
+              emailAddress: {
+                address: to,
+              },
+            },
+          ],
+          bccRecipients: bcc
+            ? [
+                {
+                  emailAddress: {
+                    address: bcc,
+                  },
+                },
+              ]
+            : undefined,
+          attachments: attachments,
+        },
+        saveToSentItems: true,
+      };
+
+      const response = await fetch(
+        `${this.apiUrl}/v1.0/users/${from}/sendMail`,
+        {
+          method: 'POST',
+          headers: {
+            Authorization: `Bearer ${token.accessToken}`,
+            'Content-Type': 'application/json',
+          },
+          body: JSON.stringify(payload),
+        }
+      );
+
+      if (!response.ok) {
+        logger.logError('Unable to send email to user', {
+          error: response.statusText + ' : ' + response.status,
+        });
+
+        throw new Error(
+          `Failed to send email. Status: ${response.status} - ${response.statusText}`
+        );
+      }
+
+      const responseData = await response.text();
+      callback(null, {
+        envelope: {
+          from: from,
+          to: [to],
+        },
+        messageId: '',
+        accepted: [],
+        rejected: [],
+        pending: [],
+        response: responseData,
+      });
+    } catch (error: any) {
+      logger.logError('Unable to send email to user', {
+        error: error,
+      });
+
+      callback(error, null);
+    }
+  }
+}
+
+export class MSGraphMailService extends TemplateMailService {
+  constructor() {
+    super();
+  }
+
+  protected createTransport(): NodeMailerTransportOptions {
+    return nodemailer.createTransport(new MSGraphTransport());
+  }
+
+  protected createAttachments() {
+    const attachments = [];
+
+    if (process.env.EMAIL_FOOTER_IMAGE_PATH !== undefined) {
+      if (existsSync(process.env.EMAIL_FOOTER_IMAGE_PATH)) {
+        attachments.push({
+          '@odata.type': '#microsoft.graph.fileAttachment',
+          name: 'logo.png',
+          contentType: 'image/png',
+          contentBytes: readFileSync(
+            process.env.EMAIL_FOOTER_IMAGE_PATH
+          ).toString('base64'),
+        });
+      } else {
+        logger.logWarn('Email footer image path does not exist', {
+          path: process.env.EMAIL_FOOTER_IMAGE_PATH,
+        });
+      }
+    }
+
+    return attachments;
+  }
+}

apps/backend/src/eventHandlers/MailService/SMTP/SMTPMailService.spec.ts

@@ -1,11 +1,11 @@
 import EmailTemplates from 'email-templates';
 import { container } from 'tsyringe';
 
+import { SMTPMailService } from './SMTPMailService';
 import { Tokens } from '../../../config/Tokens';
 import { AdminDataSource } from '../../../datasources/AdminDataSource';
 import { SettingsId } from '../../../models/Settings';
 import SendMailOptions from '../MailService';
-import { SMTPMailService } from './SMTPMailService';
 
 jest.mock('email-templates');
 const mockAdminDataSource = container.resolve(