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mod escape;
mod map;
mod seq;
mod var;
pub use crate::errors::serialize::DeError;
use crate::{
errors::Error,
events::{BytesCData, BytesEnd, BytesStart, BytesText, Event},
reader::Decoder,
Reader,
};
use serde::de::{self, Deserialize, DeserializeOwned, Visitor};
use serde::serde_if_integer128;
use std::borrow::Cow;
use std::io::BufRead;
pub(crate) const INNER_VALUE: &str = "$value";
pub(crate) const UNFLATTEN_PREFIX: &str = "$unflatten=";
pub(crate) const PRIMITIVE_PREFIX: &str = "$primitive=";
#[derive(Debug, PartialEq)]
pub enum DeEvent<'a> {
Start(BytesStart<'a>),
End(BytesEnd<'a>),
Text(BytesText<'a>),
CData(BytesCData<'a>),
Eof,
}
pub struct Deserializer<'de, R>
where
R: XmlRead<'de>,
{
reader: R,
peek: Option<DeEvent<'de>>,
has_value_field: bool,
}
pub fn from_str<'de, T>(s: &'de str) -> Result<T, DeError>
where
T: Deserialize<'de>,
{
from_slice(s.as_bytes())
}
#[deprecated = "Use `from_slice` instead"]
pub fn from_bytes<'de, T>(s: &'de [u8]) -> Result<T, DeError>
where
T: Deserialize<'de>,
{
from_slice(s)
}
pub fn from_slice<'de, T>(s: &'de [u8]) -> Result<T, DeError>
where
T: Deserialize<'de>,
{
let mut de = Deserializer::from_slice(s);
T::deserialize(&mut de)
}
pub fn from_reader<R, T>(reader: R) -> Result<T, DeError>
where
R: BufRead,
T: DeserializeOwned,
{
let mut de = Deserializer::from_reader(reader);
T::deserialize(&mut de)
}
fn deserialize_bool<'de, V>(value: &[u8], decoder: Decoder, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
#[cfg(feature = "encoding")]
{
let value = decoder.decode(value);
match value.as_ref() {
"true" | "1" | "True" | "TRUE" | "t" | "Yes" | "YES" | "yes" | "y" => {
visitor.visit_bool(true)
}
"false" | "0" | "False" | "FALSE" | "f" | "No" | "NO" | "no" | "n" => {
visitor.visit_bool(false)
}
_ => Err(DeError::InvalidBoolean(value.into())),
}
}
#[cfg(not(feature = "encoding"))]
{
match value {
b"true" | b"1" | b"True" | b"TRUE" | b"t" | b"Yes" | b"YES" | b"yes" | b"y" => {
visitor.visit_bool(true)
}
b"false" | b"0" | b"False" | b"FALSE" | b"f" | b"No" | b"NO" | b"no" | b"n" => {
visitor.visit_bool(false)
}
e => Err(DeError::InvalidBoolean(decoder.decode(e)?.into())),
}
}
}
impl<'de, R> Deserializer<'de, R>
where
R: XmlRead<'de>,
{
pub fn new(reader: R) -> Self {
Deserializer {
reader,
peek: None,
has_value_field: false,
}
}
#[deprecated = "Use `Deserializer::new` instead"]
pub fn from_borrowing_reader(reader: R) -> Self {
Self::new(reader)
}
fn peek(&mut self) -> Result<&DeEvent<'de>, DeError> {
if self.peek.is_none() {
self.peek = Some(self.reader.next()?);
}
match self.peek.as_ref() {
Some(v) => Ok(v),
None => unreachable!(),
}
}
fn next(&mut self) -> Result<DeEvent<'de>, DeError> {
if let Some(e) = self.peek.take() {
return Ok(e);
}
self.reader.next()
}
fn next_start(&mut self) -> Result<Option<BytesStart<'de>>, DeError> {
loop {
let e = self.next()?;
match e {
DeEvent::Start(e) => return Ok(Some(e)),
DeEvent::End(_) => return Err(DeError::End),
DeEvent::Eof => return Ok(None),
_ => (), }
}
}
fn next_text(&mut self, unescape: bool) -> Result<BytesCData<'de>, DeError> {
match self.next()? {
DeEvent::Text(e) if unescape => e.unescape().map_err(|e| DeError::Xml(e.into())),
DeEvent::Text(e) => Ok(BytesCData::new(e.into_inner())),
DeEvent::CData(e) => Ok(e),
DeEvent::Start(e) => {
let inner = self.next()?;
let t = match inner {
DeEvent::Text(t) if unescape => t.unescape()?,
DeEvent::Text(t) => BytesCData::new(t.into_inner()),
DeEvent::CData(t) => t,
DeEvent::Start(_) => return Err(DeError::Start),
DeEvent::End(end) if end.name() == e.name() => {
return Ok(BytesCData::new(&[] as &[u8]));
}
DeEvent::End(_) => return Err(DeError::End),
DeEvent::Eof => return Err(DeError::Eof),
};
self.read_to_end(e.name())?;
Ok(t)
}
DeEvent::End(_) => Err(DeError::End),
DeEvent::Eof => Err(DeError::Eof),
}
}
fn read_to_end(&mut self, name: &[u8]) -> Result<(), DeError> {
match self.next()? {
DeEvent::Start(e) => self.reader.read_to_end(e.name())?,
DeEvent::End(e) if e.name() == name => return Ok(()),
_ => (),
}
self.reader.read_to_end(name)
}
}
impl<'de> Deserializer<'de, SliceReader<'de>> {
pub fn from_str(s: &'de str) -> Self {
Self::from_slice(s.as_bytes())
}
pub fn from_slice(bytes: &'de [u8]) -> Self {
let mut reader = Reader::from_bytes(bytes);
reader
.expand_empty_elements(true)
.check_end_names(true)
.trim_text(true);
Self::new(SliceReader { reader })
}
}
impl<'de, R> Deserializer<'de, IoReader<R>>
where
R: BufRead,
{
pub fn from_reader(reader: R) -> Self {
let mut reader = Reader::from_reader(reader);
reader
.expand_empty_elements(true)
.check_end_names(true)
.trim_text(true);
Self::new(IoReader {
reader,
buf: Vec::new(),
})
}
}
macro_rules! deserialize_type {
($deserialize:ident => $visit:ident) => {
fn $deserialize<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let text = self.next_text(false)?;
let string = text.decode(self.reader.decoder())?;
visitor.$visit(string.parse()?)
}
};
}
impl<'de, 'a, R> de::Deserializer<'de> for &'a mut Deserializer<'de, R>
where
R: XmlRead<'de>,
{
type Error = DeError;
fn deserialize_struct<V>(
self,
_name: &'static str,
fields: &'static [&'static str],
visitor: V,
) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
if let Some(e) = self.next_start()? {
let name = e.name().to_vec();
self.has_value_field = fields.contains(&INNER_VALUE);
let map = map::MapAccess::new(self, e, fields)?;
let value = visitor.visit_map(map)?;
self.has_value_field = false;
self.read_to_end(&name)?;
Ok(value)
} else {
Err(DeError::Start)
}
}
fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let text = self.next_text(false)?;
deserialize_bool(text.as_ref(), self.reader.decoder(), visitor)
}
fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_str(visitor)
}
fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_string(visitor)
}
fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let text = self.next_text(true)?;
let string = text.decode(self.reader.decoder())?;
match string {
Cow::Borrowed(string) => visitor.visit_borrowed_str(string),
Cow::Owned(string) => visitor.visit_string(string),
}
}
fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let text = self.next_text(false)?;
visitor.visit_bytes(&text)
}
fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let text = self.next_text(false)?;
let value = text.into_inner().into_owned();
visitor.visit_byte_buf(value)
}
fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
match self.next()? {
DeEvent::Start(s) => {
self.read_to_end(s.name())?;
visitor.visit_unit()
}
DeEvent::Text(_) | DeEvent::CData(_) => visitor.visit_unit(),
DeEvent::End(_) => Err(DeError::End),
DeEvent::Eof => Err(DeError::Eof),
}
}
fn deserialize_unit_struct<V>(
self,
_name: &'static str,
visitor: V,
) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_unit(visitor)
}
fn deserialize_newtype_struct<V>(
self,
_name: &'static str,
visitor: V,
) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_tuple(1, visitor)
}
fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_seq(visitor)
}
fn deserialize_tuple_struct<V>(
self,
_name: &'static str,
len: usize,
visitor: V,
) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_tuple(len, visitor)
}
fn deserialize_enum<V>(
self,
_name: &'static str,
_variants: &'static [&'static str],
visitor: V,
) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
let value = visitor.visit_enum(var::EnumAccess::new(self))?;
Ok(value)
}
fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
visitor.visit_seq(seq::SeqAccess::new(self)?)
}
fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_struct("", &[], visitor)
}
fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
match self.peek()? {
DeEvent::Text(t) if t.is_empty() => visitor.visit_none(),
DeEvent::CData(t) if t.is_empty() => visitor.visit_none(),
DeEvent::Eof => visitor.visit_none(),
_ => visitor.visit_some(self),
}
}
fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
self.deserialize_string(visitor)
}
fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
match self.next()? {
DeEvent::Start(e) => self.read_to_end(e.name())?,
DeEvent::End(_) => return Err(DeError::End),
DeEvent::Eof => return Err(DeError::Eof),
_ => (),
}
visitor.visit_unit()
}
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, DeError>
where
V: Visitor<'de>,
{
match self.peek()? {
DeEvent::Start(_) => self.deserialize_map(visitor),
DeEvent::End(_) | DeEvent::Eof => self.deserialize_unit(visitor),
_ => self.deserialize_string(visitor),
}
}
deserialize_type!(deserialize_i8 => visit_i8);
deserialize_type!(deserialize_i16 => visit_i16);
deserialize_type!(deserialize_i32 => visit_i32);
deserialize_type!(deserialize_i64 => visit_i64);
deserialize_type!(deserialize_u8 => visit_u8);
deserialize_type!(deserialize_u16 => visit_u16);
deserialize_type!(deserialize_u32 => visit_u32);
deserialize_type!(deserialize_u64 => visit_u64);
deserialize_type!(deserialize_f32 => visit_f32);
deserialize_type!(deserialize_f64 => visit_f64);
serde_if_integer128! {
deserialize_type!(deserialize_i128 => visit_i128);
deserialize_type!(deserialize_u128 => visit_u128);
}
}
pub trait XmlRead<'i> {
fn next(&mut self) -> Result<DeEvent<'i>, DeError>;
fn read_to_end(&mut self, name: &[u8]) -> Result<(), DeError>;
fn decoder(&self) -> Decoder;
}
pub struct IoReader<R: BufRead> {
reader: Reader<R>,
buf: Vec<u8>,
}
impl<'i, R: BufRead> XmlRead<'i> for IoReader<R> {
fn next(&mut self) -> Result<DeEvent<'static>, DeError> {
let event = loop {
let e = self.reader.read_event(&mut self.buf)?;
match e {
Event::Start(e) => break Ok(DeEvent::Start(e.into_owned())),
Event::End(e) => break Ok(DeEvent::End(e.into_owned())),
Event::Text(e) => break Ok(DeEvent::Text(e.into_owned())),
Event::CData(e) => break Ok(DeEvent::CData(e.into_owned())),
Event::Eof => break Ok(DeEvent::Eof),
_ => self.buf.clear(),
}
};
self.buf.clear();
event
}
fn read_to_end(&mut self, name: &[u8]) -> Result<(), DeError> {
match self.reader.read_to_end(name, &mut self.buf) {
Err(Error::UnexpectedEof(_)) => Err(DeError::Eof),
other => Ok(other?),
}
}
fn decoder(&self) -> Decoder {
self.reader.decoder()
}
}
pub struct SliceReader<'de> {
reader: Reader<&'de [u8]>,
}
impl<'de> XmlRead<'de> for SliceReader<'de> {
fn next(&mut self) -> Result<DeEvent<'de>, DeError> {
loop {
let e = self.reader.read_event_unbuffered()?;
match e {
Event::Start(e) => break Ok(DeEvent::Start(e)),
Event::End(e) => break Ok(DeEvent::End(e)),
Event::Text(e) => break Ok(DeEvent::Text(e)),
Event::CData(e) => break Ok(DeEvent::CData(e)),
Event::Eof => break Ok(DeEvent::Eof),
_ => (),
}
}
}
fn read_to_end(&mut self, name: &[u8]) -> Result<(), DeError> {
match self.reader.read_to_end_unbuffered(name) {
Err(Error::UnexpectedEof(_)) => Err(DeError::Eof),
other => Ok(other?),
}
}
fn decoder(&self) -> Decoder {
self.reader.decoder()
}
}
#[cfg(test)]
mod tests {
use super::*;
use pretty_assertions::assert_eq;
#[test]
fn read_to_end() {
use crate::de::DeEvent::*;
let mut de = Deserializer::from_slice(
br#"
<root>
<tag a="1"><tag>text</tag>content</tag>
<tag a="2"><![CDATA[cdata content]]></tag>
<self-closed/>
</root>
"#,
);
assert_eq!(
de.next().unwrap(),
Start(BytesStart::borrowed_name(b"root"))
);
assert_eq!(
de.next().unwrap(),
Start(BytesStart::borrowed(br#"tag a="1""#, 3))
);
assert_eq!(de.read_to_end(b"tag").unwrap(), ());
assert_eq!(
de.next().unwrap(),
Start(BytesStart::borrowed(br#"tag a="2""#, 3))
);
assert_eq!(
de.next().unwrap(),
CData(BytesCData::from_str("cdata content"))
);
assert_eq!(de.next().unwrap(), End(BytesEnd::borrowed(b"tag")));
assert_eq!(
de.next().unwrap(),
Start(BytesStart::borrowed(b"self-closed", 11))
);
assert_eq!(de.read_to_end(b"self-closed").unwrap(), ());
assert_eq!(de.next().unwrap(), End(BytesEnd::borrowed(b"root")));
assert_eq!(de.next().unwrap(), Eof);
}
#[test]
fn borrowing_reader_parity() {
let s = r##"
<item name="hello" source="world.rs">Some text</item>
<item2/>
<item3 value="world" />
"##
.as_bytes();
let mut reader1 = IoReader {
reader: Reader::from_reader(s),
buf: Vec::new(),
};
let mut reader2 = SliceReader {
reader: Reader::from_bytes(s),
};
loop {
let event1 = reader1.next().unwrap();
let event2 = reader2.next().unwrap();
if let (DeEvent::Eof, DeEvent::Eof) = (&event1, &event2) {
break;
}
assert_eq!(event1, event2);
}
}
#[test]
fn borrowing_reader_events() {
let s = r##"
<item name="hello" source="world.rs">Some text</item>
<item2></item2>
<item3/>
<item4 value="world" />
"##
.as_bytes();
let mut reader = SliceReader {
reader: Reader::from_bytes(s),
};
reader
.reader
.trim_text(true)
.expand_empty_elements(true)
.check_end_names(true);
let mut events = Vec::new();
loop {
let event = reader.next().unwrap();
if let DeEvent::Eof = event {
break;
}
events.push(event);
}
use crate::de::DeEvent::*;
assert_eq!(
events,
vec![
Start(BytesStart::borrowed(
br#"item name="hello" source="world.rs""#,
4
)),
Text(BytesText::from_escaped(b"Some text".as_ref())),
End(BytesEnd::borrowed(b"item")),
Start(BytesStart::borrowed(b"item2", 5)),
End(BytesEnd::borrowed(b"item2")),
Start(BytesStart::borrowed(b"item3", 5)),
End(BytesEnd::borrowed(b"item3")),
Start(BytesStart::borrowed(br#"item4 value="world" "#, 5)),
End(BytesEnd::borrowed(b"item4")),
]
)
}
#[test]
fn borrowing_read_to_end() {
let s = " <item /> ";
let mut reader = SliceReader {
reader: Reader::from_str(s),
};
reader
.reader
.trim_text(true)
.expand_empty_elements(true)
.check_end_names(true);
assert_eq!(
reader.next().unwrap(),
DeEvent::Start(BytesStart::borrowed(b"item ", 4))
);
reader.read_to_end(b"item").unwrap();
assert_eq!(reader.next().unwrap(), DeEvent::Eof);
}
#[test]
fn next_text() {
match from_str::<String>(r#"</root>"#) {
Err(DeError::Xml(Error::EndEventMismatch { expected, found })) => {
assert_eq!(expected, "");
assert_eq!(found, "root");
}
x => panic!(
r#"Expected `Err(Xml(EndEventMismatch("", "root")))`, but found {:?}"#,
x
),
}
let s: String = from_str(r#"<root></root>"#).unwrap();
assert_eq!(s, "");
match from_str::<String>(r#"<root></other>"#) {
Err(DeError::Xml(Error::EndEventMismatch { expected, found })) => {
assert_eq!(expected, "root");
assert_eq!(found, "other");
}
x => panic!(
r#"Expected `Err(Xml(EndEventMismatch("root", "other")))`, but found {:?}"#,
x
),
}
}
}
