Add a jingle message parser and serialiser.

src/jingle_message.rs

@@ -0,0 +1,132 @@
+// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
+//
+// 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 std::convert::TryFrom;
+
+use minidom::Element;
+
+use error::Error;
+
+use jingle::SessionId;
+
+use ns;
+
+#[derive(Debug, Clone)]
+pub enum JingleMI {
+    Propose {
+        sid: SessionId,
+        // TODO: Use a more specialised type here.
+        description: Element,
+    },
+    Retract(SessionId),
+    Accept(SessionId),
+    Proceed(SessionId),
+    Reject(SessionId),
+}
+
+fn get_sid(elem: Element) -> Result<SessionId, Error> {
+    for (attr, _) in elem.attrs() {
+        if attr != "id" {
+            return Err(Error::ParseError("Unknown attribute in Jingle message element."));
+        }
+    }
+    Ok(SessionId(get_attr!(elem, "id", required)))
+}
+
+fn check_empty_and_get_sid(elem: Element) -> Result<SessionId, Error> {
+    for _ in elem.children() {
+        return Err(Error::ParseError("Unknown child in Jingle message element."));
+    }
+    get_sid(elem)
+}
+
+impl TryFrom<Element> for JingleMI {
+    type Error = Error;
+
+    fn try_from(elem: Element) -> Result<JingleMI, Error> {
+        if elem.ns() != Some(ns::JINGLE_MESSAGE) {
+            return Err(Error::ParseError("This is not a Jingle message element."));
+        }
+        Ok(match elem.name() {
+            "propose" => {
+                let mut description = None;
+                for child in elem.children() {
+                    if child.name() != "description" {
+                        return Err(Error::ParseError("Unknown child in propose element."));
+                    }
+                    if description.is_some() {
+                        return Err(Error::ParseError("Too many children in propose element."));
+                    }
+                    description = Some(child.clone());
+                }
+                JingleMI::Propose {
+                    sid: get_sid(elem)?,
+                    description: description.ok_or(Error::ParseError("Propose element doesn’t contain a description."))?,
+                }
+            },
+            "retract" => JingleMI::Retract(check_empty_and_get_sid(elem)?),
+            "accept" => JingleMI::Accept(check_empty_and_get_sid(elem)?),
+            "proceed" => JingleMI::Proceed(check_empty_and_get_sid(elem)?),
+            "reject" => JingleMI::Reject(check_empty_and_get_sid(elem)?),
+            _ => return Err(Error::ParseError("This is not a Jingle message element.")),
+        })
+    }
+}
+
+impl From<JingleMI> for Element {
+    fn from(jingle_mi: JingleMI) -> Element {
+        match jingle_mi {
+            JingleMI::Propose { sid, description } => {
+                Element::builder("propose")
+                        .ns(ns::JINGLE_MESSAGE)
+                        .attr("id", sid)
+                        .append(description)
+            },
+            JingleMI::Retract(sid) => {
+                Element::builder("retract")
+                        .ns(ns::JINGLE_MESSAGE)
+                        .attr("id", sid)
+            }
+            JingleMI::Accept(sid) => {
+                Element::builder("accept")
+                        .ns(ns::JINGLE_MESSAGE)
+                        .attr("id", sid)
+            }
+            JingleMI::Proceed(sid) => {
+                Element::builder("proceed")
+                        .ns(ns::JINGLE_MESSAGE)
+                        .attr("id", sid)
+            }
+            JingleMI::Reject(sid) => {
+                Element::builder("reject")
+                        .ns(ns::JINGLE_MESSAGE)
+                        .attr("id", sid)
+            }
+        }.build()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_simple() {
+        let elem: Element = "<accept xmlns='urn:xmpp:jingle-message:0' id='coucou'/>".parse().unwrap();
+        JingleMI::try_from(elem).unwrap();
+    }
+
+    #[test]
+    fn test_invalid_child() {
+        let elem: Element = "<propose xmlns='urn:xmpp:jingle-message:0' id='coucou'><coucou/></propose>".parse().unwrap();
+        let error = JingleMI::try_from(elem).unwrap_err();
+        let message = match error {
+            Error::ParseError(string) => string,
+            _ => panic!(),
+        };
+        assert_eq!(message, "Unknown child in propose element.");
+    }
+}

src/lib.rs

@@ -112,7 +112,7 @@ macro_rules! generate_attribute {
 macro_rules! generate_id {
     ($elem:ident) => (
         #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-        pub struct $elem(String);
+        pub struct $elem(pub String);
         impl FromStr for $elem {
             type Err = Error;
             fn from_str(s: &str) -> Result<$elem, Error> {
@@ -214,6 +214,9 @@ pub mod mam;
 /// XEP-0319: Last User Interaction in Presence
 pub mod idle;
 
+/// XEP-0353: Jingle Message Initiation
+pub mod jingle_message;
+
 /// XEP-0359: Unique and Stable Stanza IDs
 pub mod stanza_id;
 

src/ns.rs

@@ -104,6 +104,9 @@ pub const MAM: &str = "urn:xmpp:mam:2";
 /// XEP-0319: Last User Interaction in Presence
 pub const IDLE: &str = "urn:xmpp:idle:1";
 
+/// XEP-0353: Jingle Message Initiation
+pub const JINGLE_MESSAGE: &str = "urn:xmpp:jingle-message:0";
+
 /// XEP-0359: Unique and Stable Stanza IDs
 pub const SID: &str = "urn:xmpp:sid:0";