readBody returns a empty string when no body request is sent

[hidekatsu-izuno]

I sent no body request. Then readBody returns empty string. I can also send empty json string and these can not be distincted.

> await (await fetch('/api/data', {method:'POST'})).json()

await useBody() // -> ''

Shouldn't useBody return undefined when no body request sent ?

[tobiasdiez]

I had a look at this, and I don't think its possible to detect the difference between no body and an empty body (I'm not sure even if there is a difference in the actual http request). Both cases seem to result into a IncomingMessage with a buffer of length 0, see https://github.com/unjs/h3/pull/201/files#diff-27a4e7df4add81d2de697f2623191acfe289d32253fc378a3edc0c1a3f77524cR30-R51 for test cases.

This behavior is also consistent with https://github.com/stream-utils/raw-body/blob/5e59d0a9b214c2c6c4cfb3d6cdb802b2cfa3c0c8/test/index.js#L121-L135 an empty stream is converted to a buffer of length 0.

[pi0]

Fixed by 6a0abf0 in 0.8.x. I think we shall respect content-length at least and early return if non is specified with undefined value which is distinguishable from empty string (JSON)