fix: update axum generated multipart requests to own the body

[AlexandreCassagne]

This PR updates axum multipart requests (multipart and multipart-related) to give ownership of the multipart request contents to the application.

The following method on Multipart highlights the need:

pub async fn next_field(&mut self) -> Result<Option<Field<'_>>, MultipartError>

it requires &mut on the multipart argument to allow reading its contents.

In axum documentation, multipart requests are implemented with full ownership (https://docs.rs/axum/latest/axum/extract/struct.Multipart.html).

Taken from the above link, please note the order of parameters is important:

⚠️ Since extracting multipart form data from the request requires consuming the body, the Multipart extractor must be last if there are multiple extractors in a handler. See "the order of extractors"

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[wing328]

thanks for the PR

please run ./bin/generate-samples.sh ./bin/configs/manual/rust-axum-* (using WSL if you're using Windows) to update the samples

[AlexandreCassagne]

@wing328 done, will push. Is there a test that will check that the servers compile and/or successfully produce multipart?

[AlexandreCassagne]

fyi
@linxGnu
@frol @farcaller @richardwhiuk @paladinzh @jacob-pro

[wing328]

yes, there are tests: https://github.com/OpenAPITools/openapi-generator/actions/runs/15116801119/job/42489611479?pr=21301

[wing328]

can you please merge the latest master (upstream official) to your branch, build the CLI JAR locally and regenerate the samples again?

[wing328]

thanks for the PR

cc @linxGnu

[AlexandreCassagne]

@wing328 can anyone other than @linxGnu review if not available?

[wing328]

let's give it a try

thanks again for the PR

[linxGnu]

Sorry for late reply due to urgent project at my full-time job.

The PR LGTM. Also fyi @Victoria-Casasampere-BeeTheData about the changes

[AlexandreCassagne]

@wing328 am I missing something, or is this MR merged but not showing up in newer versions?

[linxGnu]

@AlexandreCassagne

Seem like there are changes between. Would you mind to make a PR to fix this (or I can make a PR on your behalf)?

Latest Commit (in master branch) already included your changes:

{{#x-consumes-multipart}}
    body: Multipart,
    {{/x-consumes-multipart}}
    {{#x-consumes-multipart-related}}
    body: axum::body::Body,

[linxGnu]

@AlexandreCassagne

In the meantime, you can use this feature flag as well: openapi-generator generate .... --additional-properties ownedRequest=true

[AlexandreCassagne]

@AlexandreCassagne

Seem like there are changes between. Would you mind to make a PR to fix this (or I can make a PR on your behalf)?

Latest Commit (in master branch) already included your changes:

{{#x-consumes-multipart}}
    body: Multipart,
    {{/x-consumes-multipart}}
    {{#x-consumes-multipart-related}}
    body: axum::body::Body,

Hey @linxGnu, I'm not sure I understand what the issue is, would you mind raising the PR and tagging me there?

Thanks!