commit 6b21fd7a7643b72f3b8583d7fff0e32c16e5afc5 Author: Alexander "PapaTutuWawa Date: Sat Feb 26 21:24:51 2022 +0100 Add File Upload Notifications diff --git a/xep-xxxx-file-upload-notification.md b/xep-xxxx-file-upload-notification.md new file mode 100644 index 0000000..7eca36f --- /dev/null +++ b/xep-xxxx-file-upload-notification.md @@ -0,0 +1,74 @@ +# File Upload Notification + +## Introduction + +When sending files relevant to a current discussion, it sometimes happens that the conversation +moves on while waiting for the file to be uploaded, for example by using [HTTP-Upload](https://xmpp.org/extensions/xep-0363.html). +This causes the file to be sent at a later date. + +File Upload Notifications are a way to allow supporting clients to place a pseudo-message +that will be replaced once the file has been uploaded. + +## Pre-Upload + +```xml + + + + vacation.jpg + image/jpeg + + + blurhash + + + + + + +``` + +The `` element indicates that a message should be replaced with the actual +file embed once the upload is done. Metadata about the file should be included +as specified by [File metadata element](https://xmpp.org/extensions/xep-0446.html). +The metadata should include only the bare minimum, i.e. the mime type and filename. +Additionally, a thumbnail can be sent with the notification in order to allow clients +to already show a preview. + +Note that [Unique and Stable Origin IDs](https://xmpp.org/extensions/xep-0359.html) must be used when the message is sent to a +groupchat. + +Since this message carries no meaning to anyone retrieving it after the file upload has been +completed, a `` element should be added (See [Message Processing Hints](https://xmpp.org/extensions/xep-0334.html)). + +## Post-Upload + +After the file upload has been completed, the sending client includes a `` element +in the message to inform clients which messages should be replaced. + +```xml + + ... + + ... + + + + +``` + +The `id` attribute of the `` element refers to either the stanza ID or the +origin ID of the message that contained the original ``. + +If sent to a groupchat, the origin ID must be used. + +Note the the actual method of communicating a file is of no relevance here, as long as the +method allows a client to show it inline. Examples for such methods are +[Out of Band Data](https://xmpp.org/extensions/xep-0066.html) +and [Stateless Inline Media Sharing](https://xmpp.org/extensions/xep-0385.html). + +## Security Considerations + +A client receiveing a message with an `` element must verify if the message it +is supposed to replace was actually sent by the sender of the `` element to +prevent arbitrary messages to be replaced.