MailDeltaFetch

Summary

• Combines Microsoft Graph delta tracking with full message retrieval so clients receive every new or updated mail (including body content) since their last stored delta token.

Graph Endpoint

• GET /me/messages/delta

• GET /me/messages/{id}

Parameters

Required

• mailDelta: string — Delta token from a prior MailDeltaFetch or MailInitDelta call. Use this to resume change tracking.

Optional

• deltaLink: string — Legacy alias for mailDelta. Only one of mailDelta or deltaLink is needed.

• folder: string — Folder ID or well-known name (e.g., Inbox). Used when starting without a token or when the token becomes invalid.

Usage (app.businessFunction)

Minimal

app.businessFunction({
  functionName: 'MicrosoftGraph',
  methodName: 'Mail',
  operation: 'DeltaFetch',
  parameters: {
    mailDelta: storedToken
  }
})

With options

app.businessFunction({
  functionName: 'MicrosoftGraph',
  methodName: 'Mail',
  operation: 'DeltaFetch',
  parameters: {
    mailDelta: storedToken,
    folder: 'Inbox'
  }
})

Response

• Returns the full messages (same shape as MailGet) plus the next delta token to persist for the following call.

{
  "items": [
    {
      "id": "AAMkAGVmM...",
      "subject": "Quarterly report",
      "from": {
        "name": "Finance",
        "address": "[e-mail]"
      },
      "toRecipients": [
        {
          "name": "Me",
          "address": "[e-mail]"
        }
      ],
      "receivedDateTime": "2025-01-16T08:22:11Z",
      "isRead": false,
      "body": {
        "contentType": "HTML",
        "content": "<p>Attached you will find...</p>"
      },
      "webLink": "https://outlook.office.com/mail/inbox/id/AAMk..."
    }
  ],
  "deltaLink": "https://graph.microsoft.com/v1.0/me/messages/delta?$deltatoken=..."
}

Notes

• Use MailInitDelta to bootstrap the first mailDelta token. Afterwards, persist the deltaLink returned by each MailDeltaFetch.

• Messages marked as removed by Microsoft Graph are skipped; clients should continue to rely on MailDelta if they need delete notifications.

• If the delta token is expired or invalid, the operation throws a friendly error so callers can fall back to MailInitDelta.