dade

dade is a framework for defining data structure to Rust structures, like pydantic in Python.

For the easy handle of data, the following will support it.

• validation for (primitive) types.
  • numeric types; u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize, f32, f64
  • boolean
  • String
  • Optional
  • Vec
  • nested model
  • enum
• export a data schema conforms JsonSchema.
• load a model from JSON.
• dump a JSON-string from a model.
• implements for useful types. e.g. URL, email and etc.
• publish a trait that for you implements any custom type with your validation.

See documentation for more details.

Roadmap

• implements for basic idea.
• implements for (primitive) types, enum, and more.
• support configuration of a model, for example, set a given name to a title in JsonSchema, or exclusion another key.
• implements for useful types and a trait for custom type.

Example

Basic

To define a model, You need the below module.

use dade::{Model, model};

For example, define user-model.

#[model]
struct User {
    #[field(ge = 1)]
    id: u64,
    #[field(min_length = 1, max_length = 100)]
    name: String,
    #[field(default = "en")]
    lang: String,
    #[field(min_length = 1, max_length = 255, default = null)]
    url: Option<String>,
    #[field(default = false)]
    verified: bool,
}

Then you create an instance of the model by the below.

let input = "{\"id\": 1, \"name\": \"James Smith\"}";
let user = User::parse(input).unwrap();

And you get a Json string for the instance by the below.

let json_string = user.json(false);
// json_string = "{\"id\":1,\"name\":\"James Smith\",\"lang\":\"en\",\"url\":null,\"verified\":false}"

If you want to validate a value, you will get a schema that conforms JsonSchema, for the given model, by the below.

let schema = User::schema();

The schema is

{
  "$ref": "#/definitions/User",
  "definitions": {
    "User": {
      "title": "User",
      "type": "object",
      "properties": {
        "id": {
          "type": "integer",
          "title": "Id",
          "minimum": 1
        },
        "name": {
          "type": "string",
          "title": "Name",
          "minLength": 1,
          "maxLength": 100
        },
        "lang": {
          "type": "string",
          "title": "Lang",
          "default": "en"
        },
        "url": {
          "type": "string",
          "title": "Url",
          "default": null,
          "minLength": 1,
          "maxLength": 255
        },
        "verified": {
          "type": "boolean",
          "title": "Verified",
          "default": false
        }
      },
      "required": ["id", "name"]
    }
  }
}

Advance

• If you want to bind other name

#[model]
struct User {
    id: u64,
    #[field(alias = "FirstName")]
    first_name: String,
    #[field(alias = "LastName")]
    last_name: String,
}

• If you need a nested model

#[model]
struct Name {
    first_name: String,
    last_name: String,
}

#[model]
struct User {
    id: u64,
    name: Name,
}

• If you need a self-reference model

#[model]
struct Item {
    id: u64,
    name: String,
    value: u128,
    related_items: Option<Vec<Box<Item>>>,
}