schemars/README.md

schemars

Generate JSON Schema documents from Rust code

Work in progress!

Basic Usage

use schemars::{JsonSchema, schema_for};
use serde::{Deserialize, Serialize};

#[derive(Deserialize, Serialize, JsonSchema)]
#[serde(rename_all = "camelCase")]
struct MyStruct {
    my_int: i32,
    my_nullable: Option<bool>,
    #[serde(default)]
    my_string: String,
    #[serde(rename = "myArray")]
    my_float_vec: Vec<f32>,
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let schema = schema_for!(MyStruct)?;
    println!("{}", serde_json::to_string_pretty(&schema)?);
    Ok(())
}

This outputs the following:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "MyStruct",
  "type": "object",
  "required": [
    "myArray",
    "myInt",
    "myNullable"
  ],
  "properties": {
    "myArray": {
      "type": "array",
      "items": {
        "type": "number",
        "format": "float"
      }
    },
    "myInt": {
      "type": "integer",
      "format": "int32"
    },
    "myNullable": {
      "type": [
        "boolean",
        "null"
      ]
    },
    "myString": {
      "type": "string"
    }
  }
}

Note that the #[serde(...)] attributes are respected.