Removing a prefix from route paths (for path API versioning)

[zedseven]

I have my routes prefixed with /v0 to have path-based API versioning. Currently, the generated OpenAPI spec lists each route with this prefix, and that causes downstream issues for code generators that use these routes.

What I'm looking to accomplish is to have Axum listening on the /v0 prefix, but have the OpenAPI spec showing the routes without it. Then I'd have a servers entry in the spec that includes the prefix as part of the server URL.

I've found #153, but that issue never got an answer.

Any help would be greatly appreciated! Thank you!

[zedseven]

Once again, I figured out the answer shortly after asking the question.

I was able to accomplish this using the following code in my OpenAPI transformation function:

fn transform_openapi(openapi: TransformOpenApi) -> TransformOpenApi {
    let api_version_prefix: String = format!("/{API_VERSION}");

    let mut openapi = openapi
        .title(PROGRAM_PROPER_NAME)
        .summary(env!("CARGO_PKG_DESCRIPTION"))
        .version(env!("CARGO_PKG_VERSION"))
        .server(Server {
            url: api_version_prefix.clone(),
            description: Some(format!("API {API_VERSION}.")),
            variables: IndexMap::default(),
            extensions: IndexMap::default(),
        });

    // Strip the API version prefix from all paths
    if let Some(paths: &mut Paths) = &mut openapi.inner_mut().paths {
        for (path: &mut String, _) in paths.paths.iter_mut2() {
            if let Some(stripped_path: &str) = path.strip_prefix(api_version_prefix.as_str()) {
                *path = stripped_path.to_owned();
            }
        }
    }

    openapi
}