openapi-trait-client

Transport-agnostic client procedural macro backend for openapi-trait.

This crate is not intended for direct use. In normal projects, depend on openapi-trait and use the re-exported macro:

#[openapi_trait::client("openapi/petstore.yaml")]
pub mod petstore {}

What it generates

Given an annotated mod, the macro reads an OpenAPI document at compile time and replaces the module contents with:

• serde-derived Rust structs for components/schemas
• {OperationId}Request structs for path, query, header, and body inputs
• {OperationId}Response enums whose variants map to HTTP status codes
• A {ModName}Client trait with one method per operationId

The generated trait name comes from the annotated module name, so mod petstore {} produces petstore::PetstoreClient.

Reqwest derive support

This crate also defines the ReqwestClient derive that powers the feature-gated blanket reqwest implementation re-exported from openapi-trait. By default, the derive expects named fields called client and base_url, and those defaults can be overridden with:

• #[openapi_trait(client)]
• #[openapi_trait(base_url)]

Path resolution

The macro resolves the OpenAPI file path relative to CARGO_MANIFEST_DIR and uses include_str! so Cargo recompiles the crate when the spec changes.

Crate role

This crate isolates client-side code generation and optional reqwest-backed integration so the public openapi-trait crate can expose a single entry point without making the proc-macro implementation details part of its API surface.