cleanups and initial XML tree implementation

src/client.rs

@@ -3,7 +3,8 @@ use transport::{Transport, SslTransport};
 use error::Error;
 use ns;
 
-use xml::writer::XmlEvent;
+use xml::writer::XmlEvent as WriterEvent;
+use xml::reader::XmlEvent as ReaderEvent;
 
 pub struct ClientBuilder {
     jid: Jid,
@@ -33,7 +34,7 @@ impl ClientBuilder {
     pub fn connect(self) -> Result<Client, Error> {
         let host = &self.host.unwrap_or(self.jid.domain.clone());
         let mut transport = SslTransport::connect(host, self.port)?;
-        transport.write_event(XmlEvent::start_element("stream:stream")
+        transport.write_event(WriterEvent::start_element("stream:stream")
                                           .attr("to", &self.jid.domain)
                                           .default_ns(ns::CLIENT)
                                           .ns("stream", ns::STREAM))?;

src/error.rs

@@ -16,6 +16,7 @@ pub enum Error {
     HandshakeError(HandshakeError<TcpStream>),
     OpenSslErrorStack(ErrorStack),
     StreamError,
+    EndOfDocument,
 }
 
 impl From<XmlError> for Error {

src/lib.rs

@@ -6,5 +6,6 @@ pub mod transport;
 pub mod error;
 pub mod jid;
 pub mod client;
+pub mod tree;
 
 mod locked_io;

src/transport.rs

@@ -9,6 +9,8 @@ use std::sync::{Arc, Mutex};
 
 use ns;
 
+use tree;
+
 use locked_io::LockedIO;
 
 use error::Error;
@@ -18,6 +20,9 @@ use openssl::ssl::{SslMethod, SslConnectorBuilder, SslStream};
 pub trait Transport {
     fn write_event<'a, E: Into<XmlWriterEvent<'a>>>(&mut self, event: E) -> Result<(), Error>;
     fn read_event(&mut self) -> Result<XmlReaderEvent, Error>;
+
+    fn write_element(&mut self, element: &tree::Element) -> Result<(), Error>;
+    fn read_element(&mut self) -> Result<tree::Element, Error>;
 }
 
 pub struct SslTransport {
@@ -36,6 +41,14 @@ impl Transport for SslTransport {
     fn read_event(&mut self) -> Result<XmlReaderEvent, Error> {
         Ok(self.reader.next()?)
     }
+
+    fn write_element(&mut self, element: &tree::Element) -> Result<(), Error> {
+        element.write_to(&mut self.writer)
+    }
+
+    fn read_element(&mut self) -> Result<tree::Element, Error> {
+        tree::Element::from_reader(&mut self.reader)
+    }
 }
 
 impl SslTransport {

src/tree.rs

@@ -0,0 +1,164 @@
+// TODO: really should either be a separate crate or implemented into xml-rs
+
+use std::io::prelude::*;
+
+use std::fmt;
+
+use xml::name::{OwnedName, Name};
+use xml::reader::{XmlEvent, EventReader};
+use xml::writer::{XmlEvent as WriterEvent, EventWriter};
+use xml::attribute::OwnedAttribute;
+
+use error::Error;
+
+#[derive(Clone)]
+pub struct Element {
+    name: OwnedName,
+    attributes: Vec<OwnedAttribute>,
+    children: Vec<Fork>,
+}
+
+impl fmt::Debug for Element {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(fmt, "<{}", self.name)?;
+        for attr in &self.attributes {
+            write!(fmt, " {}", attr)?;
+        }
+        write!(fmt, ">")?;
+        for child in &self.children {
+            match *child {
+                Fork::Element(ref e) => {
+                    write!(fmt, "{:?}", e)?;
+                },
+                Fork::Text(ref s) => {
+                    write!(fmt, "{}", s)?;
+                },
+            }
+        }
+        write!(fmt, "</{}>", self.name)?;
+        Ok(())
+    }
+}
+
+#[derive(Clone, Debug)]
+pub enum Fork {
+    Element(Element),
+    Text(String),
+}
+
+impl Element {
+    pub fn new(name: OwnedName, attributes: Vec<OwnedAttribute>) -> Element {
+        Element {
+            name: name,
+            attributes: attributes,
+            children: Vec::new(),
+        }
+    }
+
+    pub fn from_reader<R: Read>(reader: &mut EventReader<R>) -> Result<Element, Error> {
+        loop {
+            let e = reader.next()?;
+            match e {
+                XmlEvent::StartElement { name, attributes, .. } => {
+                    let mut root = Element::new(name, attributes);
+                    root.from_reader_inner(reader);
+                    return Ok(root);
+                },
+                XmlEvent::EndDocument => {
+                    return Err(Error::EndOfDocument);
+                },
+                _ => () // TODO: may need more errors
+            }
+        }
+    }
+
+    fn from_reader_inner<R: Read>(&mut self, reader: &mut EventReader<R>) -> Result<(), Error> {
+        loop {
+            let e = reader.next()?;
+            match e {
+                XmlEvent::StartElement { name, attributes, .. } => {
+                    let elem = Element::new(name, attributes);
+                    let elem_ref = self.append_child(elem);
+                    elem_ref.from_reader_inner(reader);
+                },
+                XmlEvent::EndElement { .. } => {
+                    // TODO: may want to check whether we're closing the correct element
+                    return Ok(());
+                },
+                XmlEvent::Characters(s) => {
+                    self.append_text_node(s);
+                },
+                XmlEvent::CData(s) => {
+                    self.append_text_node(s);
+                },
+                XmlEvent::EndDocument => {
+                    return Err(Error::EndOfDocument);
+                },
+                _ => (), // TODO: may need to implement more
+            }
+        }
+    }
+
+    pub fn write_to<W: Write>(&self, writer: &mut EventWriter<W>) -> Result<(), Error> {
+        let start = WriterEvent::start_element(self.name.borrow());
+        writer.write(start)?;
+        for child in &self.children {
+            match *child {
+                Fork::Element(ref e) => {
+                    e.write_to(writer)?;
+                },
+                Fork::Text(ref s) => {
+                    writer.write(WriterEvent::characters(s))?;
+                },
+            }
+        }
+        writer.write(WriterEvent::end_element())?;
+        Ok(())
+    }
+
+    pub fn children<'a>(&'a self) -> Children<'a> {
+        unimplemented!();
+    }
+
+    pub fn children_mut<'a>(&'a mut self) -> ChildrenMut<'a> {
+        unimplemented!();
+    }
+
+    pub fn append_child(&mut self, child: Element) -> &mut Element {
+        self.children.push(Fork::Element(child));
+        if let Fork::Element(ref mut cld) = *self.children.last_mut().unwrap() {
+            cld
+        }
+        else {
+            unreachable!()
+        }
+    }
+
+    pub fn append_text_node(&mut self, child: String) {
+        self.children.push(Fork::Text(child));
+    }
+
+    pub fn text(&self) -> &str {
+        unimplemented!()
+    }
+
+    pub fn get_child<'a, N: Into<Name<'a>>>(&self, name: N) -> Option<&Element> {
+        unimplemented!()
+    }
+
+    pub fn get_child_mut<'a, N: Into<Name<'a>>>(&mut self, name: N) -> Option<&mut Element> {
+        unimplemented!()
+    }
+
+    pub fn into_child<'a, N: Into<Name<'a>>>(self, name: N) -> Option<Element> {
+        unimplemented!()
+    }
+}
+
+pub struct Children<'a> {
+    elem: &'a Element,
+}
+
+pub struct ChildrenMut<'a> {
+    elem: &'a mut Element,
+}