MS Graph has provided an API support to open files by hitting /preview API.
The parameters that the API expects are in the context of Files since the expected parameter item-id is available only when we hit /children API and the same id for the same attachment is not available when we fetch conversation by hitting /getConversations.
We plan to match the e-tag value and the attachment-id in absence of any API to map both the responses to get item-id? Does that look correct from the implementation perspective?
Also Can anyone suggest if there is another API to open files when we do not have the item-id with us?
Response of /getConversations with attachment details :