Microsoft Graph API transport for Nodemailer

This module is a transport plugin for Nodemailer
that use Microsoft Graph API
to send e-mails from a tenant.

Usage

$3

1. Go to Microsoft Entra admin center
2. Click on App registrations then New registration
3. Give a name, leave other parameters as default (single tenant, no redirect
URL)
4. Register the new app
5. Keep the Application (Client) ID and Directory (Tenant) ID

#### Create a secret
1. Go to Manage -> Certificates and secrets
2. New client secret, give it a name
3. Keep the client secret value

#### Add graph permissions
1. Go to Manage -> API permissions
2. Add a permission
3. Select Microsoft Graph then Application permissions
4. Search for Mail.Send, select it and click on Add permissions
5. Click on Grant admin consent for "your tenant"

$3

Install via npm

npm install nodemailer-msgraph-transport

Require the module and intialize it with the Microsoft application credentials

``javascript
const nodemailer = require('nodemailer')
const MsGraphTransport = required('nodemailer-msgraph-transport')

const msGraphConfig = {
clientId: 'MS_GRAPH_CLIENT_ID',
tenantId: 'MS_GRAPH_TENANT_ID',
clientSecret: 'MS_GRAPH_TENANT_SECRET_VALUE',
userPrincipalName: 'id | userPrincipalName'
saveToSentItems: true
}

const msGraphTransport = new MsgraphTransport(msGraphConfig)

const transporter = nodemailer.createTransport(msGraphTransport)
`

userPrincipalName and saveToSentItems can be overridden for each mail
in the message object passed to `sendMail()`

When sending a batch of e-mails, you can request a token before hand to avoid
unnecessary requests to Microsoft graph api authentication server. The token
will be automatically cached.

`javascript
await msGraphTransport.getAccessToken()

transporter.sendMail(mailData)
transporter.sendMail(mailData)
...
``

Limitations

Attachements are currently not supported.

References

- SendMail graph function: https://learn.microsoft.com/en-us/graph/api/user-sendmail
- graph message: https://learn.microsoft.com/en-us/graph/api/resources/message

Licence

Licensed under the MIT Licence.