Struct jomini::BinaryDeserializer

source · [−]

pub struct BinaryDeserializer;

Expand description

A structure to deserialize binary data into Rust values.

By default, if a token is unable to be resolved then it will be ignored by the default. Construct a custom instance through the builder method to tweak this behavior.

The example below demonstrates multiple ways to deserialize data

use jomini::{BinaryDeserializer, BinaryFlavor, Encoding, JominiDeserialize, Windows1252Encoding};
use serde::Deserialize;
use std::{borrow::Cow, collections::HashMap};

#[derive(Debug, Clone, Deserialize, PartialEq)]
pub struct StructA {
  #[serde(flatten)]
  b: StructB,

  #[serde(flatten)]
  c: StructC,
}

#[derive(Debug, Clone, Deserialize, PartialEq)]
pub struct StructB {
  field1: String,
}

#[derive(Debug, Clone, Deserialize, PartialEq)]
pub struct StructC {
  field2: String,
}

#[derive(Debug, Default)]
pub struct BinaryTestFlavor;

impl BinaryFlavor for BinaryTestFlavor {
    fn visit_f32(&self, data: [u8; 4]) -> f32 {
        f32::from_le_bytes(data)
    }

    fn visit_f64(&self, data: [u8; 8]) -> f64 {
        f64::from_le_bytes(data)
    }
}

impl Encoding for BinaryTestFlavor {
    fn decode<'a>(&self, data: &'a [u8]) -> Cow<'a, str> {
        Windows1252Encoding::decode(data)
    }
}

let data = [
   0x82, 0x2d, 0x01, 0x00, 0x0f, 0x00, 0x03, 0x00, 0x45, 0x4e, 0x47,
   0x83, 0x2d, 0x01, 0x00, 0x0f, 0x00, 0x03, 0x00, 0x45, 0x4e, 0x48,
];

let mut map = HashMap::new();
map.insert(0x2d82, String::from("field1"));
map.insert(0x2d83, String::from("field2"));

// the data can be parsed and deserialized in one step

let a: StructA = BinaryDeserializer::builder_flavor(BinaryTestFlavor)
    .from_slice(&data[..], &map)?;
assert_eq!(a, StructA {
  b: StructB { field1: "ENG".to_string() },
  c: StructC { field2: "ENH".to_string() },
});

// or split into two steps, whatever is appropriate.
let tape = jomini::BinaryTape::from_slice(&data[..])?;
let deserializer = BinaryDeserializer::builder_flavor(BinaryTestFlavor);
let b: StructB = deserializer.from_tape(&tape, &map)?;
let c: StructC = deserializer.from_tape(&tape, &map)?;
assert_eq!(b, StructB { field1: "ENG".to_string() });
assert_eq!(c, StructC { field2: "ENH".to_string() });