Schemas

Requires the schema Cargo feature, which is not enabled by default.

The other feature of Schematic is the ability to model schemas for Rust types using the Schematic trait and associated macro. Schemas are useful for:

• Generating code, documentation, and other formats.
• Ensuring data integrity across systems.
• Standardizing interoperability and enforcing contracts.

Usage

Define a struct, enum, or type and derive the Schematic trait. Our macro will attempt to convert all fields, variants, values, and generics into a schema representation using SchemaType.

#![allow(unused)]
fn main() {
use schematic::Schematic;

#[derive(Schematic)]
enum UserStatus {
	Active,
	Inactive,
}

#[derive(Schematic)]
struct User {
	pub name: String;
	pub age: usize;
	pub status: UserStatus;
}
}

Once a type has a schema associated with it, it can be fed into the generator.

Custom implementation

Our derive macro will always implement schemas using the default state of Schema, SchemaType, and associated types. If you want these types to use custom settings, you can implement the Schematic trait and Schematic::build_schema() method manually.

The Schematic::schema_name() method is optional, but is encouraged for non-primitive types. It will associate references between types, and avoid circular references.

#![allow(unused)]
fn main() {
use schematic::{Schematic, Schema, SchemaBuilder, SchemaType, schema::*};

#[derive(Schematic)]
enum UserStatus {
	Active,
	Inactive,
}

struct User {
	pub name: String;
	pub age: usize;
	pub status: UserStatus;
}

impl Schematic for User {
	fn schema_name() -> Option<String> {
		Some("User".into())
	}

	fn build_schema(mut schema: SchemaBuilder) -> Schema {
		schema.structure(StructType::new([
			("name".into(), schema.nest().string(StringType {
				min_length: Some(1),
				..StringType::default()
			})),
			("age".into(), schema.nest().integer(IntegerType::new_kind(IntegerKind::Usize))),
			("status".into(), schema.infer::<UserStatus>()),
		]))
	}
}
}

Learn more about our supported types.

Cargo features

The following Cargo features are available:

Renderers

Learn more about renderers.

• renderer_json_schema - Enables JSON schema generation.
• renderer_template - Enables config template generation.
• renderer_typescript - Enables TypeScript types generation.

External types

Learn more about external types.

• type_chrono - Implements schematic for the chrono crate.
• type_indexmap - Implements schematic for the indexmap crate.
• type_regex - Implements schematic for the regex crate.
• type_relative_path - Implements schematic for the relative-path crate.
• type_rust_decimal - Implements schematic for the rust_decimal crate.
• type_semver - Implements schematic for the semver crate.
• type_url - Implements schematic for the url crate.