[fix] handle binary data when prerendering

[gbkwiatt]

fixes #5088

body was always converted using response.text() which was always decoded with UTF-8 which then is breaking buffers

I understand that this only solved problem with images, this is just to illustrate the issue, and maybe someone can come up with better solution

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[Rich-Harris]

thank you!

as mentioned inline, I have some concerns about using Buffer.from here. i also think we need some tests before we can merge this

[gbkwiatt]

thank you!

as mentioned inline, I have some concerns about using Buffer.from here. i also think we need some tests before we can merge this

From myself, I can only say that your fix works fine on the project I am working on. It was a mix of content-type

null
image/svg+xml
text/html
application/xml
text/plain
image/jpeg
text/html

[gbkwiatt]

@Rich-Harris I wonder if you can assist me with writing the test. I am not really familiar with repo structure, I've started writing route for the image kit/packages/kit/test/prerendering/basics/src/
to be prerendered and saved. But not sure what am I missing as it's not being saved in build folder even with crawl enabled.
The idea was to test Buffers with output file and input file, although I am not sure that's what you want to test in here since you said you have doubts with Buffer.from.

[Rich-Harris]

Do you have an <img src="/path/to/route.jpg"> somewhere in the test app?

[gbkwiatt]

Do you have an <img src="/path/to/route.jpg"> somewhere in the test app?

Yes that was it, I've had wrong path to image. I've pushed tests, not sure if it's sufficient but it's testing the problem I was facing.

[Rich-Harris]

thank you!