@@ -173,3 +173,58 @@ pub fn try_from_element<T: FromXml>(
// implementations must be constructible from that.
unreachable!("minidom::Element did not produce enough events to complete element")
}
+
+fn map_nonio_error<T>(r: Result<T, rxml::Error>) -> Result<T, self::error::Error> {
+ match r {
+ Ok(v) => Ok(v),
+ Err(rxml::Error::IO(_)) => unreachable!(),
+ Err(rxml::Error::Xml(e)) => Err(e.into()),
+ Err(rxml::Error::InvalidUtf8Byte(_)) => Err(self::error::Error::Other("invalid utf-8")),
+ Err(rxml::Error::InvalidChar(_)) => {
+ Err(self::error::Error::Other("non-character encountered"))
+ }
+ Err(rxml::Error::RestrictedXml(_)) => Err(self::error::Error::Other("restricted xml")),
+ }
+}
+
+fn read_start_event<I: std::io::BufRead>(
+ r: &mut rxml::Reader<I>,
+) -> Result<(rxml::QName, rxml::AttrMap), self::error::Error> {
+ for ev in r {
+ match map_nonio_error(ev)? {
+ rxml::Event::XmlDeclaration(_, rxml::XmlVersion::V1_0) => (),
+ rxml::Event::StartElement(_, name, attrs) => return Ok((name, attrs)),
+ _ => {
+ return Err(self::error::Error::Other(
+ "Unexpected event at start of document",
+ ))
+ }
+ }
+ }
+ Err(self::error::Error::XmlError(
+ rxml::error::XmlError::InvalidEof("before start of element"),
+ ))
+}
+
+/// Attempt to parse a type implementing [`FromXml`] from a byte buffer
+/// containing XML data.
+pub fn from_bytes<T: FromXml>(mut buf: &[u8]) -> Result<T, self::error::Error> {
+ let mut reader = rxml::Reader::new(&mut buf);
+ let (name, attrs) = read_start_event(&mut reader)?;
+ let mut builder = match T::from_events(name, attrs) {
+ Ok(v) => v,
+ Err(self::error::FromEventsError::Mismatch { .. }) => {
+ return Err(self::error::Error::TypeMismatch)
+ }
+ Err(self::error::FromEventsError::Invalid(e)) => return Err(e),
+ };
+ for ev in reader {
+ match builder.feed(map_nonio_error(ev)?)? {
+ Some(v) => return Ok(v),
+ None => (),
+ }
+ }
+ Err(self::error::Error::XmlError(
+ rxml::error::XmlError::InvalidEof("while parsing FromXml impl"),
+ ))
+}