#serde #serialization #json


Support for the Valve Data Format for Serde

3 releases (breaking)

0.3.0 Aug 31, 2020
0.2.0 Aug 31, 2020
0.1.0 Aug 31, 2020

#595 in Encoding

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Used in csgo-gsi


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Support for the Valve Data Format for Serde.

Based on the steamy-vdf VDF parser library.


Add this to your Cargo.toml:

vdf-serde = "0.3.0"

Simple Example

use serde::{Serialize, Deserialize};

#[derive(Serialize, Deserialize, Debug, PartialEq)]
struct Example {
    thing: String,
    other_thing: bool,
    more_stuff: Inner,

#[derive(Serialize, Deserialize, Debug, PartialEq)]
struct Inner {
    bonus_content: u8,
    coolness: f64,

let vdf_data = "\"Example\"
let data = Example {
    thing: "hello".to_string(),
    other_thing: true,
    more_stuff: Inner {
        bonus_content: 69,
        coolness: 420.1337,

assert_eq!(vdf_serde::to_string(&data)?, vdf_data);
assert_eq!(vdf_serde::from_str::<Example>(vdf_data)?, data);


The VDF format is rather drastically underspecified, so until I figure out a way to implement them in a way that's compatible with existing VDF files, the following types from the Serde data model are unsupported:

  • byte array
  • option
  • unit ()
  • unit_struct struct WillNotWork;
  • newtype_variant enum Broken { Example(u8) }
  • seq Vec<T>
  • tuple
  • tuple_struct struct Unsupported(u8, bool, char);
  • tuple_variant enum Bad { NotWorking(u8, bool, char) }
  • struct_variant enum Nope { NotHappening { datum: u8 } }

You might wind up needing to implement Serialize yourself and implement Deserialize yourself if you use anything like this. The rest of the Serde data model works, though, although maps with non-atomic keys might be a bit of a mess.

use std::collections::HashMap as Map;
use serde::{Serialize, Deserialize};
#[derive(Serialize, Deserialize, Debug, PartialEq)]
enum UnitVariants { A, B }
#[derive(Serialize, Deserialize, Debug, PartialEq)]
struct NewtypeStruct(u8);
#[derive(Serialize, Deserialize, Debug, PartialEq)]
struct KitchenSink {
    a: bool,
    b: i8,
    c: i16,
    d: i32,
    e: i64,
    f: u8,
    g: u16,
    h: u32,
    i: u64,
    j: f32,
    k: f64,
    l: char,
    m: String,
    n: UnitVariants,
    o: NewtypeStruct,
    p: Map<String, String>,

let data = KitchenSink { // yada yada yada
assert_eq!(data, vdf_serde::from_str(&vdf_serde::to_string(&data)?)?);


Licensed under either of

at your option.


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.


v0.3.0 - 2020-08-31

  • Use name attached to top-level newtype

v0.2.0 - 2020-08-31

  • More useful errors
  • Don't error if text remaining after deserialize is all whitespace

v0.1.0 - 2020-08-31

  • Initial release


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