REST API question : downloading attachments

[nigelgomm]

If I drag and drop an email attachment from a web outlook (that is from https://outlook.office.com/mail/inbox open in a browser)  to my desktop application I see the following JSON string in the drop event.

attachmentV{"itemType":"attachment","attachmentFile":{"attachmentItemId":"AAMkADhmNz......","name":"feb invoices archive.pdf","size":64276,"fileType":5,"type":"ItemIdAttachment:#Exchange"}}

so I have the attachmentItemId but no messageId…. And yet the only endpoints I see for the rest API require a messageId.

e.g. GET https://outlook.office.com/api/v2.0/me/messages/{message_id}/attachments/{attachment_id}

Is there a way to download an attachment without knowing the message id? Or of finding the messageid that this attachment belongs to?

[#2]

best i could find so far is to search messages for the file name

.../messages/?$search="attachment:{Name}"&$expand=Attachments

and then loop through the returned messages and their attachments looking for the specific id.

not ideal... but it's working.

n.b. you have to replace any "/" characters with "-" and any "+" with "_" in the attachmentid when comparing with the id returned in the search.