Add StanzaTimeInfo for <delay> (XEP-0203)

xmpp/src/delay.rs

@@ -0,0 +1,65 @@
+// Copyright (c) 2023 xmpp-rs contributors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+use chrono::{DateTime, Utc};
+use tokio_xmpp::{
+    parsers::{delay::Delay, message::Message, ns},
+    Jid,
+};
+
+/// Time information associated with a stanza.
+///
+/// Contains information about when the message was received, and any claim about when it was sent.
+#[derive(Debug, Clone)]
+pub struct StanzaTimeInfo {
+    /// Time information when the message was received by the library
+    pub received: DateTime<Utc>,
+
+    /// Time information claimed by the sender or an intermediary.
+    ///
+    /// **Warning**: this has security implications. See [XEP-0203 security section](https://xmpp.org/extensions/xep-0203.html#security).
+    pub delays: Vec<Delay>,
+}
+
+impl StanzaTimeInfo {
+    pub fn delay_from(&self, jid: &Jid) -> Option<&Delay> {
+        self.delays.iter().find(|delay| {
+            if let Some(from) = &delay.from {
+                return from == jid;
+            }
+            return false;
+        })
+    }
+}
+
+/// Parsing a [`Message`], store the current time it was processed, as well [XEP-0203](https://xmpp.org/extensions/xep-0203.html#protocol)
+/// [`Delay`] contained in the message's payloads.
+///
+/// Specifically, this method will look for any <delay/> element in the message's payloads. If they were found,
+/// they will be added to the [`StanzaTimeInfo`] result.
+pub fn message_time_info(message: &Message) -> StanzaTimeInfo {
+    let mut delays = vec![];
+
+    // Scan the message payloads for XEP-0203 delays.
+    for payload in &message.payloads {
+        if payload.is("delay", ns::DELAY) {
+            match Delay::try_from(payload.clone()) {
+                Ok(delay) => delays.push(delay),
+                Err(e) => {
+                    error!("Wrong <delay> format in payload from {}:{}\n{:?}\nUsing received time only.",
+                    message.from.as_ref().unwrap().to_owned(),
+                    e,
+                    payload);
+                }
+            }
+        }
+    }
+
+    StanzaTimeInfo {
+        received: Utc::now(),
+        delays,
+    }
+}