Serialization and Deserialization (serde)

Serialization and Deserialization

https://serde.rs

Serialize & Deserialize

To make a Rust structure (de)serializable:

#[derive(Debug, serde::Serialize, serde::Deserialize)]
struct Move {
    id: usize,
    direction: Direction,
}

#[derive(Debug, serde::Serialize, serde::Deserialize)]
enum Direction { North, South, East, West }

Formats

Serde supports a number of formats, such as:

• JSON
• CBOR
• YAML
• TOML
• BSON
• MessagePack
• ... More!

Did you enjoy that acronym salad?

Serialize

To JSON:

use serde::{Serialize, Deserialize};

#[derive(Debug, Serialize, Deserialize)]
struct Move {
    id: usize,
    direction: Direction,
}

#[derive(Debug, Serialize, Deserialize)]
enum Direction { North, South, East, West }

fn main() {
    let action = Move { id: 1, direction: West };
    let payload = serde_json::to_string(&action);
    println!("{:?}", payload);
}

Deserialize

From JSON:

use serde::{Serialize, Deserialize};

#[derive(Debug, Serialize, Deserialize)]
struct Move {
    id: usize,
    direction: Direction,
}

#[derive(Debug, Serialize, Deserialize)]
enum Direction { North, South, East, West }

fn main() {
    let payload = r#"{ "id": 1, "direction": "West" }"#;
    let action = serde_json::from_str::<Move>(&payload);
    println!("{:?}", action);
}

Transcode

use serde::{Serialize, Deserialize};
use serde_transcode::transcode;

#[derive(Debug, Serialize, Deserialize)]
struct Move {
    id: usize,
    direction: Direction,
}

#[derive(Debug, Serialize, Deserialize)]
enum Direction { North, South, East, West }

fn main() {
    let payload = r#"{ "id": 1, "direction": "West" }"#;
    let mut buffer = String::new();
    {
        let mut ser = toml::Serializer::new(&mut buffer);
        let mut de = serde_json::Deserializer::from_str(&payload);
        transcode(&mut de, &mut ser)
            .unwrap();
    }
    println!("{:?}", buffer);
}

Attributes

serde has a large number of attributes you can utilize:

#[serde(deny_unknown_fields)] // Be extra strict
struct Move {
    #[serde(default)] // Call usize::default()
    id: usize,
    #[serde(rename = "dir")] // Use a different name
    direction: Direction,
}

https://serde.rs/attributes.html