Crate keyvalues_serde

keyvalues-serde

keyvalues-serde is a (de)serialization library for VDF text v1 built on the serde framework. This library leverages keyvalues-parser for parsing and rendering the keyvalues text. This makes it easy to deal with VDF text files using strongly typed Rust structures.

Installation

Just add the following to your Cargo.toml

[dependencies]
keyvalues-serde = "0.1.0"
serde = { version = "1.0.0", features = ["derive"] }

Quickstart

use serde::Deserialize;

// Contents take from my ~/.data/Steam/steam/games/PlatformMenu.vdf
const VDF_TEXT: &str = r##"
// this file defines the contents of the platform menu
"Platform"
{
    "Menu"
    {
        "Games"
        {
            "dll"       "steamui"
            "interface" "SteamUIGames001"
            "MenuName"  "#Steam_Games"
            "SteamApp"  "1"
        }
        "Friends"
        {
            "dll"       "bin/friendsui"
            "interface" "VGuiModuleTracker001"
            "MenuName"  "#App_Friends"
        }
        "Servers"
        {
            "dll"       "bin/serverbrowser"
            "interface" "VGuiModuleServerBrowser001"
            "MenuName"  "#App_Servers"
        }
        "Settings"
        {
            "dll"       "steamui"
            "interface" "VGuiModuleSettings001"
            "MenuName"  "#App_Settings"
            "SteamApp"  "1"
        }
    }
}
"##;

#[derive(Deserialize, Debug)]
struct Platform {
    #[serde(rename = "Menu")]
    menu: Menu,
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "PascalCase")]
struct Menu {
    games: MenuModule,
    friends: MenuModule,
    servers: MenuModule,
    settings: MenuModule,
}

#[derive(Deserialize, Debug)]
struct MenuModule {
    dll: String,
    interface: String,
    #[serde(rename = "MenuName")]
    menu_name: String,
    #[serde(rename = "SteamApp")]
    steam_app: Option<bool>,
}

fn main() -> keyvalues_serde::Result<()> {
    let platform: Platform = keyvalues_serde::from_str(VDF_TEXT)?;
    println!("{:#?}", platform);

    Ok(())
}

Datatypes

Supported

• Primitive Types
  • bool
  • i8, i16, i32, i64, i128
  • u8, u16, u32, u64, u128
  • f32, f64
  • char
• String
• Option
  • VDF doesn’t have the concept of a null type, so an optional value is considered Some if present and None if missing
• Unit Variant Enum
  • Represented as text matching the variant name
• Newtype Struct
  • Considered just a wrapper over the contained data type
• Homogeneous Sequences (Vec-like types)
  • Represented as several pairs with the same key
• Heterogeneous Sequences (tuple-like types)
  • Represented as several pairs with the same key
• TupleStruct
  • Considered a wrapper over the contained tuple
• Map (HashMap-like types)
  • Represented by a list of pairs contained within curly-braces {}
• Struct
  • The same as Map. The name of the struct is ignored unless it’s the used for the top-level key

Unsupported

Type	Reasoning
Byte Array	No clear VDF representation
Unit	No clear VDF representation
Unit Struct	No clear VDF representation
Enum-containers (newtype, tuple, and struct variants)	The only clear usage would be the untagged representation in which case the ambiguity of types (everything is essentially just strings or objects) allows for too many footguns for me to be comfortable supporting

Potential Pitfalls

• Any sequence types containing Options may lead to unexpected ordering issues since a None is just omitted
  • For instance a tuple containing an Option in the middle will be very problematic
• Empty Vecs and Options with None are both omitted when serializing.
• Nested sequences are impossible to represent due to the limited nature of sequences in VDF (AFAIK)

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

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.

Re-exports

• pub use keyvalues_parser as parser;

Modules

• de
  Deserialize VDF text to Rust types
• error
  Contains error information for keyvalues-serde
• ser
  Serialize Rust types to VDF text

Structs

• Deserializer
  The struct that handles deserializing VDF into Rust structs
• Serializer
  The struct for serializing Rust values into VDF text

Enums

• Error
  All the possible errors that can be encountered when (de)serializing VDF text

Functions

• from_reader
• from_reader_with_key
• from_str
  Attempts to deserialize a string of VDF text to some type T
• from_str_with_key
  The same as from_str(), but also returns the top level VDF key
• from_vdf
• from_vdf_with_key
• to_string
  Attempts to serialize some input to VDF text
• to_string_with_key
  Attempts to serialize some input to VDF text with a custom top level VDF key
• to_writer
  Serialize the value into an IO stream of VDF text
• to_writer_with_key
  Serialize the value into an IO stream of VDF text with a custom top level VDF key

Type Aliases

• Result
  Alias for the result with Error as the error type