1//! Contains wrapper for `<stream:features/>`
 2
 3use crate::error::AuthError;
 4use xmpp_parsers::{ns, Element};
 5
 6/// Wraps `<stream:features/>`, usually the very first nonza of an
 7/// XMPPStream.
 8///
 9/// TODO: should this rather go into xmpp-parsers, kept in a decoded
10/// struct?
11#[derive(Debug)]
12pub struct StreamFeatures(pub Element);
13
14impl StreamFeatures {
15    /// Wrap the nonza
16    pub fn new(element: Element) -> Self {
17        StreamFeatures(element)
18    }
19
20    /// Can initiate TLS session with this server?
21    pub fn can_starttls(&self) -> bool {
22        self.0.get_child("starttls", ns::TLS).is_some()
23    }
24
25    /// Iterate over SASL mechanisms
26    pub fn sasl_mechanisms<'a>(&'a self) -> Result<impl Iterator<Item = String> + 'a, AuthError> {
27        Ok(self
28            .0
29            .get_child("mechanisms", ns::SASL)
30            .ok_or(AuthError::NoMechanism)?
31            .children()
32            .filter(|child| child.is("mechanism", ns::SASL))
33            .map(|mech_el| mech_el.text()))
34    }
35
36    /// Does server support user resource binding?
37    pub fn can_bind(&self) -> bool {
38        self.0.get_child("bind", ns::BIND).is_some()
39    }
40}