2021-05-23 10:55:19 +08:00

346 lines
8.7 KiB
Rust

/// Serialization.
use serde::ser::{self, Serialize};
use error::{Error, Result};
use sciter::{Value};
/// Serialize the given data structure into Sciter value.
pub fn to_value<T: ?Sized + Serialize>(value: &T) -> Result<Value> {
let mut p = Serializer { output: Value::new() };
value.serialize(&mut p)?;
Ok(p.output)
}
/// Implementation of serialization.
pub struct Serializer {
output: Value,
}
// Helper structure for serialization of sequence data types (array, map, tuple ans so on).
#[doc(hidden)]
pub struct SeqSerializer<'a> {
ser: &'a mut Serializer,
output: Value,
key: Option<Value>,
outer: Option<Value>,
}
impl<'a> SeqSerializer<'a> {
fn typed(ser: &'a mut Serializer, typed: Value) -> Self {
SeqSerializer {
ser: ser,
output: typed,
key: None,
outer: None,
}
}
fn with_outer(ser: &'a mut Serializer, outer: Value, typed: Value) -> Self {
SeqSerializer {
ser: ser,
output: typed,
key: None,
outer: Some(outer),
}
}
}
// serde traits implementation
impl<'a> ser::SerializeSeq for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
self.ser.output = self.output;
Ok(())
}
fn serialize_element<T: ?Sized + Serialize>(&mut self, value: &T) -> Result<()> {
let dst = to_value(value)?;
self.output.push(dst);
Ok(())
}
}
impl<'a> ser::SerializeMap for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
fn serialize_entry<K, V>(&mut self, key: &K, value: &V) -> Result<()> where K: ?Sized + Serialize, V: ?Sized + Serialize {
self.output.set_item(to_value(key)?, to_value(value)?);
Ok(())
}
fn serialize_key<T: ?Sized + Serialize>(&mut self, key: &T) -> Result<()> {
self.key = Some(to_value(key)?);
Ok(())
}
fn serialize_value<T: ?Sized + Serialize>(&mut self, value: &T) -> Result<()> {
let key = self.key.take();
self.output.set_item(key.unwrap(), to_value(value)?);
Ok(())
}
}
impl<'a> ser::SerializeStruct for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
fn serialize_field<T: ?Sized + Serialize>(&mut self, key: &'static str, value: &T) -> Result<()> {
self.output.set_item(key, to_value(value)?);
Ok(())
}
}
impl<'a> ser::SerializeStructVariant for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
// self.output: map
// self.outer: left key
let mut result = Value::new();
result.set_item(self.outer.unwrap(), self.output);
self.ser.output = result;
Ok(())
}
fn serialize_field<T: ?Sized + Serialize>(&mut self, key: &'static str, value: &T) -> Result<()> {
self.output.set_item(key, to_value(value)?);
Ok(())
}
}
impl<'a> ser::SerializeTuple for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
fn serialize_element<T: ?Sized + Serialize>(&mut self, value: &T) -> Result<()> {
ser::SerializeSeq::serialize_element(self, value)
}
}
impl<'a> ser::SerializeTupleStruct for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
fn serialize_field<T: ?Sized + Serialize>(&mut self, value: &T) -> Result<()> {
ser::SerializeSeq::serialize_element(self, value)
}
}
impl<'a> ser::SerializeTupleVariant for SeqSerializer<'a> {
type Ok = ();
type Error = Error;
fn end(self) -> Result<()> {
// self.output: array
// self.outer: left key
let mut result = Value::new();
result.set_item(self.outer.unwrap(), self.output);
self.ser.output = result;
Ok(())
}
fn serialize_field<T: ?Sized + Serialize>(&mut self, value: &T) -> Result<()> {
ser::SerializeSeq::serialize_element(self, value)
}
}
impl<'a> ser::Serializer for &'a mut Serializer {
type Ok = ();
type Error = Error;
type SerializeSeq = SeqSerializer<'a>;
type SerializeTuple = SeqSerializer<'a>;
type SerializeTupleStruct = SeqSerializer<'a>;
type SerializeTupleVariant = SeqSerializer<'a>;
type SerializeMap = SeqSerializer<'a>;
type SerializeStruct = SeqSerializer<'a>;
type SerializeStructVariant = SeqSerializer<'a>;
fn serialize_bool(self, v: bool) -> Result<()> {
self.output = v.into();
Ok(())
}
fn serialize_i8(self, v: i8) -> Result<()> {
self.serialize_i32(v as i32)
}
fn serialize_i16(self, v: i16) -> Result<()> {
self.serialize_i32(v as i32)
}
fn serialize_i32(self, v: i32) -> Result<()> {
self.output = v.into();
Ok(())
}
fn serialize_u8(self, v: u8) -> Result<()> {
self.serialize_i32(v as i32)
}
fn serialize_u16(self, v: u16) -> Result<()> {
self.serialize_i32(v as i32)
}
fn serialize_u32(self, v: u32) -> Result<()> {
if v <= i32::max_value() as u32 {
self.serialize_i32(v as i32)
} else {
self.serialize_f64(v as f64)
}
}
fn serialize_i64(self, _v: i64) -> Result<()> {
Err(Error::UnsupportedType)
}
fn serialize_u64(self, _v: u64) -> Result<()> {
Err(Error::UnsupportedType)
}
// Float values.
fn serialize_f32(self, v: f32) -> Result<()> {
self.serialize_f64(v as f64)
}
fn serialize_f64(self, v: f64) -> Result<()> {
self.output = v.into();
Ok(())
}
// A single character is passed as a string.
fn serialize_char(self, v: char) -> Result<()> {
self.serialize_str(&v.to_string())
}
// String itself.
fn serialize_str(self, v: &str) -> Result<()> {
self.output = v.into();
Ok(())
}
// Binary bytes.
fn serialize_bytes(self, v: &[u8]) -> Result<()> {
self.output = Value::from(v);
Ok(())
}
// A `None` value of `Option` type in Rust.
fn serialize_none(self) -> Result<()> {
self.output = Value::null();
Ok(())
}
// Some value of `Option` type in Rust.
fn serialize_some<T>(self, v: &T) -> Result<()> where T: ?Sized + Serialize {
v.serialize(self)
}
// The type of `()` in Rust.
fn serialize_unit(self) -> Result<()> {
self.serialize_none()
}
// A named value containing no data, like `struct Unit;`.
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
self.serialize_none()
}
// Enums. Serialized as an externally tagged enum representation,
// see https://serde.rs/enum-representations.html.
// A unit variant of enum, like `E::A` of `enum E { A, B }`.
fn serialize_unit_variant(self, _name: &'static str, _index: u32, value: &'static str)
-> Result<()>
{
// `"A"`
self.serialize_str(value)
}
// For example the `E::N` in `enum E { N(u8) }`.
fn serialize_newtype_variant<T>(self, _name: &'static str, _index: u32, variant: &'static str, value: &T)
-> Result<()> where T: ?Sized + Serialize
{
// `{ "N": u8 }`
self.output.set_item(to_value(variant)?, to_value(value)?);
Ok(())
}
// For example the `E::T` in `enum E { T(u8, u8) }`.
fn serialize_tuple_variant(self, _name: &'static str, _index: u32, value: &'static str, _len: usize)
-> Result<Self::SerializeTupleVariant>
{
// `{ "T": [u8, u8] }`
let left = to_value(value)?;
Ok(SeqSerializer::with_outer(self, left, Value::array(0)))
}
// For example the `E::S` in `enum E { S { r: u8, g: u8, b: u8 } }`.
fn serialize_struct_variant(self, _name: &'static str, _index: u32, value: &'static str, _len: usize)
-> Result<Self::SerializeStructVariant>
{
// `{ "S": {r: u8, g: u8, b: u8} }`
let left = to_value(value)?;
Ok(SeqSerializer::with_outer(self, left, Value::map()))
}
// New-type struct, like `struct Celcius(u32)`.
fn serialize_newtype_struct<T>(self, _name: &'static str, value: &T) -> Result<()>
where T: ?Sized + Serialize
{
// Serialize the inner itself.
value.serialize(self)
}
// A variably sized heterogeneous sequence of values, for example `Vec<T>` or `HashSet<T>`.
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
// let init = if let Some(size) = len { Value::array(size) } else { Value::new() };
Ok(SeqSerializer::typed(self, Value::array(0)))
}
// A statically sized heterogeneous sequence of values, `[u64; 10]`, `(u8,)` or `(String, u64, Vec<T>)`.
fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple> {
self.serialize_seq(Some(len))
}
// A named tuple, for example `struct Rgb(u8, u8, u8)`.
fn serialize_tuple_struct(self, _name: &'static str, len: usize) -> Result<Self::SerializeTupleStruct> {
self.serialize_seq(Some(len))
}
// A heterogeneous key-value pairing, for example `BTreeMap<K, V>`.
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap> {
Ok(SeqSerializer::typed(self, Value::map()))
}
// A heterogeneous key-value pairing , for example `struct S { r: u8, g: u8, b: u8 }`.
fn serialize_struct(self, _name: &'static str, len: usize) -> Result<Self::SerializeStruct> {
self.serialize_map(Some(len))
}
}