[rust] set useAsyncFileStream only for files in the body

[ThomasVille]

In a previous PR ([Rust ]Add async file stream support for reqwest client): the useAsyncFileStream and vendorExtensions.useAsyncFileStream template variables are used in case there's at least one file uploaded in the body, but they are set as long as supportAsync is set and any parameter is a file (including if the file is in a form). So these variables are set more often than they should, introducing unused dependencies on tokio.

This explains why on master, these tests have the tokio dependency even though they don't use it:

• samples/client/petstore/rust/reqwest/petstore-async-tokensource/Cargo.toml
• samples/client/petstore/rust/reqwest/petstore-async-middleware/Cargo.toml
• samples/client/petstore/rust/reqwest/petstore-async/Cargo.toml
• samples/client/petstore/rust/reqwest/petstore-avoid-box/Cargo.toml

This PR sets the useAsyncFileStream and vendorExtensions.useAsyncFileStream template variables only when at least one body parameter is a file.

This PR doesn't break the feature introduced by [Rust ]Add async file stream support for reqwest client, as can be seen in the samples/client/others/rust/reqwest/file-streaming example.

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[wing328]

thanks for the PR

is it possible to add a new workflow (or updating the exiting one) to catch the issue moving forward?

[ThomasVille]

@wing328 Which workflow are you referring to?

I'm not sure how we could catch this issue. Maybe we could call RUSTFLAGS: "-D warnings" cargo build to make sure the generated code builds and doesn't produce any warning like unused code?

[ThomasVille]

Ah I just saw that some tests are disabled in this workflow:

openapi-generator/.github/workflows/samples-rust.yaml

Line 53 in bd0b81d

# Skip samples/client/petstore/rust/ as its tests are failing.

.

[ThomasVille]

@wing328 Since there's no such test (making sure the build doesn't produce any warning) today, if I add it in this PR, I risk having to fix all sorts of errors introduced before and that are not related to this PR.

So maybe we can open another issue to add this workflow?

[wing328]

agreed.

i'll take a look over the weekend to see why the rust client tests are skipped.

have you tested this fix locally in your environment to confirm it fixes the mentioned issue?

if yes, i'll get it merged so that more users can test the change after merge

[ThomasVille]

@wing328 Yes I tested it locally on my own project and it works on the petstore samples too.

[wing328]

fyi. rust client ci fixed via #21851