Structs

The StructType can be used to represent a struct with explicitly named fields and typed values. This is also known as a “shape” or “model”.

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

impl Schematic for T {
	fn build_schema(mut schema: SchemaBuilder) -> Schema {
		schema.structure(StructType {
			fields: IndexMap::from_iter([
				(
					"name".into(),
					Box::new(SchemaField {
						comment: Some("Name of the user".into()),
						schema: schema.infer::<String>(),
						..SchemaField::default()
					})
				),
				(
					"age".into(),
					Box::new(SchemaField {
						comment: Some("Age of the user".into()),
						schema: schema.nest().integer(IntegerType::new_kind(IntegerKind::U16)),
						..SchemaField::default()
					})
				),
				(
					"active".into(),
					Box::new(SchemaField {
						comment: Some("Is the user active".into()),
						schema: schema.infer::<bool>(),
						..SchemaField::default()
					})
				),
			]),
			..StructType::default()
		})
	}
}
}

If you’re only defining fields, you can use the shorthand StructType::new() method. When using this approach, the Boxs are automatically inserted for you.

#![allow(unused)]
fn main() {
schema.structure(StructType::new([
	(
		"name".into(),
		SchemaField {
			comment: Some("Name of the user".into()),
			schema: schema.infer::<String>(),
			..SchemaField::default()
		}
	),
	// ...
]));
}

Automatically implemented for Duration, SystemTime, Range, and RangeInclusive. These look like scalars but serde encodes them as maps, so the schema describes the map.

Fields keep the order they were inserted in, which is the declaration order when the schema comes from a derive. Generators sort them by name when rendering, so generated output stays alphabetical regardless of how the source type is written.

Settings

The following fields can be passed to StructType, which are then fed into the generator.

Required fields

The required field can be used to specify a list of fields that are required for the struct.

#![allow(unused)]
fn main() {
StructType {
	// ...
	required: Some(vec!["name".into()]),
}
}

This is primarily used by JSON Schema.