bipack_ru/src/de.rs

258 lines
8.5 KiB
Rust

use serde::de::{
self, DeserializeSeed, MapAccess, SeqAccess,
Visitor,
};
use serde::{Serialize};
use serde::Deserialize;
use crate::bipack_source::{BipackSource, VecSource};
use crate::error::{Error, Result};
use crate::ser::to_bytes;
use crate::tools::to_dump;
pub struct Deserializer {
// This string starts with the input data and characters are truncated off
// the beginning as data is parsed.
input: VecSource,
}
pub fn from_bytes<'de,T: Deserialize<'de>>(source: Vec<u8>) -> Result<T> {
let mut des = Deserializer { input: VecSource::from(source)};
T::deserialize(&mut des)
}
impl<'de, 'a> de::Deserializer<'de> for &'a mut Deserializer {
type Error = Error;
fn deserialize_any<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
Err(Error::NotPossible)
}
fn deserialize_bool<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_bool(if self.input.get_u8()? == 0 { false } else { true } )
}
fn deserialize_i8<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_i8(self.input.get_i8()?)
}
fn deserialize_i16<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_i16(self.input.get_signed()? as i16)
}
fn deserialize_i32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_i32(self.input.get_signed()? as i32)
}
fn deserialize_i64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_i64(self.input.get_signed()?)
}
fn deserialize_u8<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_u8(self.input.get_u8()?)
}
fn deserialize_u16<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_u16(self.input.get_unsigned()? as u16)
}
fn deserialize_u32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_u32(self.input.get_unsigned()? as u32)
}
fn deserialize_u64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_u64(self.input.get_unsigned()?)
}
fn deserialize_f32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
Err(Error::NotImplemented)
}
fn deserialize_f64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
Err(Error::NotImplemented)
}
fn deserialize_char<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
let ch = self.input.get_str()?;
if ch.len() != 1 {
Err(Error::BadFormat(format!("Char length is {}, should be 1 {:?}", ch.len(), ch)))
}
else {
visitor.visit_char(ch.chars().next().unwrap())
}
}
fn deserialize_str<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_string( self.input.get_str()?)
}
fn deserialize_string<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_string(self.input.get_str()?)
}
fn deserialize_bytes<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_byte_buf(self.input.get_var_bytes()?)
}
fn deserialize_byte_buf<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_byte_buf(self.input.get_var_bytes()?)
}
fn deserialize_option<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
let marker = self.input.get_u8()?;
if marker == 0 {
visitor.visit_none()
} else {
visitor.visit_some(self)
}
}
fn deserialize_unit<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_unit()
}
fn deserialize_unit_struct<V>(self, name: &'static str, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
self.deserialize_unit(visitor)
}
fn deserialize_newtype_struct<V>(self, name: &'static str, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_newtype_struct(self)
}
fn deserialize_seq<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
let size = self.input.get_unsigned()? as usize;
visitor.visit_seq(SimpleSeq::new(self, size))
}
fn deserialize_tuple<V>(self, len: usize, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_seq(SimpleSeq::new(self, len))
}
fn deserialize_tuple_struct<V>(self, name: &'static str, len: usize, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_seq(SimpleSeq::new(self, len))
}
fn deserialize_map<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
let size = self.input.get_unsigned()?;
visitor.visit_map(SimpleMap { de: self, size: size as usize} )
}
fn deserialize_struct<V>(self, name: &'static str, fields: &'static [&'static str], visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
visitor.visit_seq(SimpleSeq::new(self, fields.len() ))
}
fn deserialize_enum<V>(self, name: &'static str, variants: &'static [&'static str], visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
todo!()
}
fn deserialize_identifier<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
Err(Error::NotPossible)
}
fn deserialize_ignored_any<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
Err(Error::NotPossible)
}
fn is_human_readable(&self) -> bool {
false
}
}
struct SimpleSeq<'a> {
de: &'a mut Deserializer,
size: usize,
}
impl<'a> SimpleSeq<'a> {
fn new(de: &'a mut Deserializer,size: usize) -> Self {
SimpleSeq {
de,
size: size,
}
}
}
// `SeqAccess` is provided to the `Visitor` to give it the ability to iterate
// through elements of the sequence.
impl<'de, 'a> SeqAccess<'de> for SimpleSeq<'a> {
type Error = Error;
fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>>
where
T: DeserializeSeed<'de>,
{
if self.size < 1 {
return Ok(None);
}
self.size -= 1;
seed.deserialize(&mut *self.de).map(Some)
}
}
struct SimpleMap<'a> {
de: &'a mut Deserializer,
size: usize,
}
impl<'de, 'a> MapAccess<'de> for SimpleMap<'a> {
type Error = Error;
fn next_key_seed<K>(&mut self, seed: K) -> std::result::Result<Option<K::Value>, Self::Error> where K: DeserializeSeed<'de> {
if self.size < 1 {
Ok(None)
}
else {
self.size -= 1;
seed.deserialize(&mut *self.de).map(Some)
}
}
fn next_value_seed<V>(&mut self, seed: V) -> std::result::Result<V::Value, Self::Error> where V: DeserializeSeed<'de> {
seed.deserialize(&mut *self.de)
}
}
#[test]
fn test_ints() -> Result<()> {
// #[derive(Deserialize, PartialEq, Debug)]
// struct Test {
// int: u32,
// seq: Vec<String>,
// }
let b = vec![7];
assert_eq!( 7u8, from_bytes(vec![7u8])?);
// let j = r#"{"int":1,"seq":["a","b"]}"#;
// let expected = Test {
// int: 1,
// seq: vec!["a".to_owned(), "b".to_owned()],
// };
// assert_eq!(expected, from_str(j).unwrap());
Ok(())
}
#[test]
fn test_struct_de() -> Result<()> {
#[derive(Serialize, Deserialize, PartialEq, Debug)]
struct Test {
int: u32,
seq: Vec<String>,
}
let expected = Test {
int: 1,
seq: vec!["a".to_owned(), "b".to_owned()],
};
let packed = to_bytes(&expected)?;
println!("::{}", to_dump(&packed));
let unpacked: Test = from_bytes(packed)?;
println!("::{:?}", unpacked);
Ok(())
// let j = r#"{"int":1,"seq":["a","b"]}"#;
// assert_eq!(expected, from_str(j).unwrap());
}