Expand description

This crate gives static type information for primitives and commonly used types from the standard library and other commonly used libraries chrono, indexmap, linked-hash-map, time and uuid when the according feature is enabled. Also, it provides a derive macro for structs and enums to gain access to their static type information at runtime.

The core of this crate is the OpenapiType trait. It has one static function, schema, which returns an OpenapiSchema. This assembles the static type information in a way that is convenient to use for a generated OpenAPI specification, but can also be utilized in other use cases as well.

Custom Types

To gain access to the static type information of your custom types at runtime, the easiest way is to use the derive macro:

struct FooBar {
	foo: String,
	bar: u64

OpenAPI specification

Using above type, running FooBar::schema().into_schema() yields

type: object
title: FooBar
    type: string
    type: integer
    format: int64
    minimum: 0
  - foo
  - bar

Note, however, that this is not sufficient for more complex types. If one of your structs fields is a type that has a name (that is, Type::schema().name is not None), above schema will contain a reference to that schema. Therefore, always remember to put the dependencies into the specification alongside the type you are interested in.


pub use indexmap;
pub use openapiv3;




This trait needs to be implemented by every type that is being used in the OpenAPI Spec. It gives access to the OpenapiSchema of this type. It is provided for primitive types, String and the like. For use on your own types, there is a derive macro:

This trait can be used to visit a type. Call one of the methods on this trait exactly once.

Derive Macros

The derive macro for OpenapiType.