JSON to Rust

About the JSON to Rust

The JSON to Rust converter generates Rust structs that derive serde Serialize and Deserialize from a JSON sample. Fields use snake_case with #[serde(rename)] for the original keys, arrays become Vec<T>, null and missing values become Option<T>, and unknown values use serde_json::Value.

Conversion happens in your browser, so your files and records stay private.

How to use the JSON to Rust

1. Paste a JSON sample and set the root struct name.
2. Add serde (with the derive feature) and serde_json to Cargo.toml.
3. Copy the structs and parse with serde_json::from_str::<User>(&text).

Example

{
  "id": 7,
  "fullName": "Grace Hopper",
  "email": null,
  "roles": ["admin"],
  "team": { "name": "Compilers", "size": 4 },
  "projects": [
    { "name": "COBOL", "year": 1959 },
    { "name": "A-0", "year": 1952, "archived": true }
  ]
}

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct User {
    pub id: i64,
    #[serde(rename = "fullName")]
    pub full_name: String,
    pub email: serde_json::Value,
    pub roles: Vec<String>,
    pub team: Team,
    pub projects: Vec<Project>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Project {
    pub name: String,
    pub year: i64,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub archived: Option<bool>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Team {
    pub name: String,
    pub size: i64,
}

Common mistakes

• Forgetting the derive feature. Without features = ["derive"] on serde, #[derive(Serialize, Deserialize)] does not compile. Add it in Cargo.toml.
• Unexpected nulls. A field typed String fails to parse when the API sends null. Wrap fields that can be null in Option<T>.

Works well with the JSON to Rust

• JSON Formatter: tidy and check the JSON before generating types.
• JSON to TypeScript: generate matching TypeScript interfaces for the front end.
• JSON Validator: find syntax errors in the sample first.

Frequently asked questions