jingle_message.rs

  1// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
  2//
  3// This Source Code Form is subject to the terms of the Mozilla Public
  4// License, v. 2.0. If a copy of the MPL was not distributed with this
  5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
  6
  7use crate::jingle::SessionId;
  8use crate::ns;
  9use crate::util::error::Error;
 10use crate::Element;
 11use std::convert::TryFrom;
 12
 13/// Defines a protocol for broadcasting Jingle requests to all of the clients
 14/// of a user.
 15#[derive(Debug, Clone)]
 16pub enum JingleMI {
 17    /// Indicates we want to start a Jingle session.
 18    Propose {
 19        /// The generated session identifier, must be unique between two users.
 20        sid: SessionId,
 21
 22        /// The application description of the proposed session.
 23        // TODO: Use a more specialised type here.
 24        description: Element,
 25    },
 26
 27    /// Cancels a previously proposed session.
 28    Retract(SessionId),
 29
 30    /// Accepts a session proposed by the other party.
 31    Accept(SessionId),
 32
 33    /// Proceed with a previously proposed session.
 34    Proceed(SessionId),
 35
 36    /// Rejects a session proposed by the other party.
 37    Reject(SessionId),
 38}
 39
 40fn get_sid(elem: Element) -> Result<SessionId, Error> {
 41    check_no_unknown_attributes!(elem, "Jingle message", ["id"]);
 42    Ok(SessionId(get_attr!(elem, "id", Required)))
 43}
 44
 45fn check_empty_and_get_sid(elem: Element) -> Result<SessionId, Error> {
 46    check_no_children!(elem, "Jingle message");
 47    get_sid(elem)
 48}
 49
 50impl TryFrom<Element> for JingleMI {
 51    type Error = Error;
 52
 53    fn try_from(elem: Element) -> Result<JingleMI, Error> {
 54        if !elem.has_ns(ns::JINGLE_MESSAGE) {
 55            return Err(Error::ParseError("This is not a Jingle message element."));
 56        }
 57        Ok(match elem.name() {
 58            "propose" => {
 59                let mut description = None;
 60                for child in elem.children() {
 61                    if child.name() != "description" {
 62                        return Err(Error::ParseError("Unknown child in propose element."));
 63                    }
 64                    if description.is_some() {
 65                        return Err(Error::ParseError("Too many children in propose element."));
 66                    }
 67                    description = Some(child.clone());
 68                }
 69                JingleMI::Propose {
 70                    sid: get_sid(elem)?,
 71                    description: description.ok_or(Error::ParseError(
 72                        "Propose element doesn’t contain a description.",
 73                    ))?,
 74                }
 75            }
 76            "retract" => JingleMI::Retract(check_empty_and_get_sid(elem)?),
 77            "accept" => JingleMI::Accept(check_empty_and_get_sid(elem)?),
 78            "proceed" => JingleMI::Proceed(check_empty_and_get_sid(elem)?),
 79            "reject" => JingleMI::Reject(check_empty_and_get_sid(elem)?),
 80            _ => return Err(Error::ParseError("This is not a Jingle message element.")),
 81        })
 82    }
 83}
 84
 85impl From<JingleMI> for Element {
 86    fn from(jingle_mi: JingleMI) -> Element {
 87        match jingle_mi {
 88            JingleMI::Propose { sid, description } => {
 89                Element::builder("propose", ns::JINGLE_MESSAGE)
 90                    .attr("id", sid)
 91                    .append(description)
 92            }
 93            JingleMI::Retract(sid) => {
 94                Element::builder("retract", ns::JINGLE_MESSAGE).attr("id", sid)
 95            }
 96            JingleMI::Accept(sid) => Element::builder("accept", ns::JINGLE_MESSAGE).attr("id", sid),
 97            JingleMI::Proceed(sid) => {
 98                Element::builder("proceed", ns::JINGLE_MESSAGE).attr("id", sid)
 99            }
100            JingleMI::Reject(sid) => Element::builder("reject", ns::JINGLE_MESSAGE).attr("id", sid),
101        }
102        .build()
103    }
104}
105
106#[cfg(test)]
107mod tests {
108    use super::*;
109
110    #[cfg(target_pointer_width = "32")]
111    #[test]
112    fn test_size() {
113        assert_size!(JingleMI, 76);
114    }
115
116    #[cfg(target_pointer_width = "64")]
117    #[test]
118    fn test_size() {
119        assert_size!(JingleMI, 152);
120    }
121
122    #[test]
123    fn test_simple() {
124        let elem: Element = "<accept xmlns='urn:xmpp:jingle-message:0' id='coucou'/>"
125            .parse()
126            .unwrap();
127        JingleMI::try_from(elem).unwrap();
128    }
129
130    #[test]
131    fn test_invalid_child() {
132        let elem: Element =
133            "<propose xmlns='urn:xmpp:jingle-message:0' id='coucou'><coucou/></propose>"
134                .parse()
135                .unwrap();
136        let error = JingleMI::try_from(elem).unwrap_err();
137        let message = match error {
138            Error::ParseError(string) => string,
139            _ => panic!(),
140        };
141        assert_eq!(message, "Unknown child in propose element.");
142    }
143}