Sending mails through Graph API, using .NET8

Usage

Constructor

SMTPClient(Secrets secrets)
SMTPClient(string TenantId, string ClientId, string ClientSecret)

Get GraphClient

async Task GetGraphServiceClientMe() // Get for ME
async Task GetGraphServiceClientUsers() // Get for USERS

Make message

static Message MakeMessage(string torecipient, string subject, string body) // Html, single recipient
static Message MakeMessage(string[] torecipients, string subject, string body) // Html, multiple recipients
static Message MakeMessage(string[] torecipients, string[] ccrecipients, string[] bccrecipients, string subject, string body) // Html, multiple to, cc, bcc
static Message MakeMessage(string[] torecipients, string[] ccrecipients, string[] bccrecipients, string subject, string body, BodyType bodyType) // multiple to, cc, bcc

Send message

async Task SendMailMe(Message message) // Sent by ME
async Task SendMailMe(Message message, bool SaveToSent) // Sent by ME, save it to sent items
async Task SendMailUsers(string senderUpn, Message message) // Sent by senderUpn
async Task SendMailUsers(string senderUpn, Message message, bool SaveToSent)// Sent by senderUpn, save it to sent items

Type 1: Me

Sending as logged in user. Requires CODE login since it uses DeviceCodeCredential to connect to your user account.
Azure App setup:

• Register app, name, etc.
• Api permission: Mail.Send, delegated. Grant admin concent.
• Create secret
• Authentication -> Allow public client flows (enable)

Type 2: Any user

Sending as typed username (upn or objectId). Requires that the "target" user has an mailbox.
Azure App setup:

• Register app, name, etc.
• Api permission: Mail.Send, application. Grant admin concent.
• Create secret.

Secrets file

To support my testclient

• secret.json file
• application.json
• application.development.json

One of them is required.

{
  "SmtpMe": {
    "TenantId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "AppName": "Personal Email Sender",
    "ClientId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "ClientSecret": "yoursecret"
  },
  "SmtpUsers": {
    "TenantId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "AppName": "Anonymous Email Sender",
    "ClientId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",,
    "ClientSecret": "yoursecret"
  }
}