Response FileBlob.slice() return full file

[gornostay25]

@Jarred-Sumner
if I return a slice, I will receive a full file

return new Response(Bun.file(data.abs).slice(opts.start, opts.end), {
            headers: data.headers,
            status: code
})

So I try to return an arrayBuffer

return new Promise((rs) => {
    Bun.file(data.abs).slice(opts.start, opts.end).arrayBuffer().then(arbf => {
        rs(
            new Response(arbf, {
                headers: data.headers,
                status: code
            })
        )
    })
})

It's work, but in docs slice return FileBlob (slice(begin?: number, end?: number): FileBlob;)
And Response constructor receive FileBlob **NOT arrayBuffer **

declare class Response implements BlobInterface {
  constructor(body: BlobPart | BlobPart[], options?: ResponseInit);

Originally posted by @gornostay25 in #589 (comment)

[Electroid]

Hi @gornostay25, thanks for submitting this bug report. If you have time, do you mind providing an example that we can run to observe the issue? I tried to piece together what you provided but I don't think there's enough context.

[gornostay25]

Hi @Electroid, check this file https://github.com/gornostay25/svelte-adapter-bun/blob/3c218a4a7728da96b0676fe3ecc3b3cbdd66ed26/src/sirv.js

[Jarred-Sumner]

In the HTTP server (Bun.serve) right? If so, HTTP or HTTPS?

[gornostay25]

https://github.com/gornostay25/svelte-adapter-bun/blob/3c218a4a7728da96b0676fe3ecc3b3cbdd66ed26/src/sirv.js#L88-L96

function return promise to Bun.serve hendler

HTTP

[Jarred-Sumner]

Is the workaround calling .arrayBuffer() or is that intentional? If it’s not intentional, could you try directly passing

new Response(Bun.file(data.abs).slice(opts.start, opts.end), { headers: data.headers, status: code })

[gornostay25]

I don't know is it working now, but early it doesn't

[Lucifer1662]

Should these lines contain this.offset?
Otherwise sendfile/splice/copy_file_range will send from the begging of the src, which will ignore the .slice operation on the blob.
As both ReadFile and WriteFile classes use the offset, which would explain why .arrayBuffer() would work.

[gornostay25]

Fixed. https://github.com/oven-sh/bun#streaming-files-with-bunserve