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?
11pub struct StreamFeatures(pub Element);
12
13impl StreamFeatures {
14    /// Wrap the nonza
15    pub fn new(element: Element) -> Self {
16        StreamFeatures(element)
17    }
18
19    /// Can initiate TLS session with this server?
20    pub fn can_starttls(&self) -> bool {
21        self.0.get_child("starttls", ns::TLS).is_some()
22    }
23
24    /// Iterate over SASL mechanisms
25    pub fn sasl_mechanisms<'a>(&'a self) -> Result<impl Iterator<Item = String> + 'a, AuthError> {
26        Ok(self
27            .0
28            .get_child("mechanisms", ns::SASL)
29            .ok_or(AuthError::NoMechanism)?
30            .children()
31            .filter(|child| child.is("mechanism", ns::SASL))
32            .map(|mech_el| mech_el.text()))
33    }
34
35    /// Does server support user resource binding?
36    pub fn can_bind(&self) -> bool {
37        self.0.get_child("bind", ns::BIND).is_some()
38    }
39}