byte range issue

[iowelinux]

Hi,

Seems like an issue with byte range requests.

E.g.
File size: 210720491 bytes

When I send a request with the header "Range: bytes=95644624-" fasthttp handles it correctly.
However if we'll modify the header to "Range: bytes=95644624-210720491" (from 95644624 to the last byte of the file) it drops to 416 http error because it can't handle the byte range.

cannot parse byte range "bytes=97851544-210720491" for path="/some_file.dat": invalid byte range

For instance I've just checked Nginx and it handles the same query correctly.

[valyala]

Thanks for the bug report, @iowelinux .

According to byte range RFC:

The last-byte-pos value gives the byte-offset of the last byte in the range; that is, the byte positions specified are inclusive. Byte offsets start at zero.

This means that the last byte of your file must be 210720490, not 210720491. It looks like nginx has a workaround for this one-off error, since the error is quite widespread. I'm investigating this further and will add the corresponding workaround if required.

[valyala]

Nginx implements new byte range RFC, which allows out-of-range end position. See the corresponding commit and the corresponding RFC:

If the last-byte-pos value is absent, or if the value is greater than or equal to the current length of the entity-body, last-byte-pos is taken to be equal to one less than the current length of the entity- body in bytes.

I'll implement the same in fasthttp

[valyala]

Fixed.