use either::Either;
use multer::Multipart;
use crate::data::{Data, Limits, Outcome};
use crate::form::prelude::*;
use crate::http::{RawStr, Status};
use crate::request::{local_cache_once, Request};
type Result<'r, T> = std::result::Result<T, Error<'r>>;
type Field<'r, 'i> = Either<ValueField<'r>, DataField<'r, 'i>>;
pub struct MultipartParser<'r, 'i> {
request: &'r Request<'i>,
buffer: &'r SharedStack<String>,
source: Multipart<'r>,
done: bool,
}
pub struct RawStrParser<'r> {
buffer: &'r SharedStack<String>,
source: &'r RawStr,
}
pub enum Parser<'r, 'i> {
Multipart(MultipartParser<'r, 'i>),
RawStr(RawStrParser<'r>),
}
impl<'r, 'i> Parser<'r, 'i> {
pub async fn new(
req: &'r Request<'i>,
data: Data<'r>,
) -> Outcome<'r, Parser<'r, 'i>, Errors<'r>> {
let parser = match req.content_type() {
Some(c) if c.is_form() => Self::from_form(req, data).await,
Some(c) if c.is_form_data() => Self::from_multipart(req, data).await,
_ => return Outcome::Forward((data, Status::UnsupportedMediaType)),
};
match parser {
Ok(storage) => Outcome::Success(storage),
Err(e) => Outcome::Error((e.status(), e.into())),
}
}
async fn from_form(req: &'r Request<'i>, data: Data<'r>) -> Result<'r, Parser<'r, 'i>> {
let limit = req.limits().get("form").unwrap_or(Limits::FORM);
let string = data.open(limit).into_string().await?;
if !string.is_complete() {
Err((None, Some(limit.as_u64())))?;
}
Ok(Parser::RawStr(RawStrParser {
buffer: local_cache_once!(req, SharedStack::new()),
source: RawStr::new(local_cache_once!(req, string.into_inner())),
}))
}
async fn from_multipart(req: &'r Request<'i>, data: Data<'r>) -> Result<'r, Parser<'r, 'i>> {
let boundary = req
.content_type()
.ok_or(multer::Error::NoMultipart)?
.param("boundary")
.ok_or(multer::Error::NoBoundary)?;
let form_limit = req.limits().get("data-form").unwrap_or(Limits::DATA_FORM);
let stream = data.open(form_limit + 1);
let constraints = multer::Constraints::new().size_limit(
multer::SizeLimit::new()
.whole_stream(form_limit.into())
.per_field(form_limit.into()),
);
Ok(Parser::Multipart(MultipartParser {
request: req,
buffer: local_cache_once!(req, SharedStack::new()),
source: Multipart::with_reader_with_constraints(stream, boundary, constraints),
done: false,
}))
}
pub async fn next(&mut self) -> Option<Result<'r, Field<'r, 'i>>> {
match self {
Parser::Multipart(ref mut p) => p.next().await,
Parser::RawStr(ref mut p) => p.next().map(|f| Ok(Either::Left(f))),
}
}
}
impl<'r> RawStrParser<'r> {
pub fn new(buffer: &'r SharedStack<String>, source: &'r RawStr) -> Self {
RawStrParser { buffer, source }
}
}
impl<'r> Iterator for RawStrParser<'r> {
type Item = ValueField<'r>;
fn next(&mut self) -> Option<Self::Item> {
use std::borrow::Cow::*;
let (name, value) = loop {
if self.source.is_empty() {
return None;
}
let (field_str, rest) = self.source.split_at_byte(b'&');
self.source = rest;
if !field_str.is_empty() {
break field_str.split_at_byte(b'=');
}
};
trace!(%name, %value, "url-encoded field");
let name_val = match (name.url_decode_lossy(), value.url_decode_lossy()) {
(Borrowed(name), Borrowed(val)) => (name, val),
(Borrowed(name), Owned(v)) => (name, self.buffer.push(v)),
(Owned(name), Borrowed(val)) => (self.buffer.push(name), val),
(Owned(mut name), Owned(val)) => {
let len = name.len();
name.push_str(&val);
self.buffer.push_split(name, len)
}
};
Some(ValueField::from(name_val))
}
}
impl<'r, 'i> MultipartParser<'r, 'i> {
async fn next(&mut self) -> Option<Result<'r, Field<'r, 'i>>> {
if self.done {
return None;
}
let field = match self.source.next_field().await {
Ok(Some(field)) => field,
Ok(None) => return None,
Err(e) => {
self.done = true;
return Some(Err(e.into()));
}
};
trace!(?field, "multipart field");
let content_type = field.content_type().and_then(|m| m.as_ref().parse().ok());
let field = if let Some(content_type) = content_type {
let (name, file_name) = match (field.name(), field.file_name()) {
(None, None) => ("", None),
(None, Some(file_name)) => ("", Some(self.buffer.push(file_name))),
(Some(name), None) => (self.buffer.push(name), None),
(Some(a), Some(b)) => {
let (field_name, file_name) = self.buffer.push_two(a, b);
(field_name, Some(file_name))
}
};
Either::Right(DataField {
content_type,
request: self.request,
name: NameView::new(name),
file_name: file_name.map(crate::fs::FileName::new),
data: Data::from(field),
})
} else {
let (mut buf, len) = match field.name() {
Some(s) => (s.to_string(), s.len()),
None => (String::new(), 0),
};
match field.text().await {
Ok(text) => buf.push_str(&text),
Err(e) => return Some(Err(e.into())),
};
let name_val = self.buffer.push_split(buf, len);
Either::Left(ValueField::from(name_val))
};
Some(Ok(field))
}
}
#[cfg(test)]
mod raw_str_parse_tests {
use crate::form::ValueField as Field;
#[test]
fn test_skips_empty() {
let buffer = super::SharedStack::new();
let fields: Vec<_> = super::RawStrParser::new(&buffer, "a&b=c&&&c".into()).collect();
assert_eq!(
fields,
&[Field::parse("a"), Field::parse("b=c"), Field::parse("c")]
);
}
#[test]
fn test_decodes() {
let buffer = super::SharedStack::new();
let fields: Vec<_> = super::RawStrParser::new(&buffer, "a+b=c%20d&%26".into()).collect();
assert_eq!(fields, &[Field::parse("a b=c d"), Field::parse("&")]);
}
}