The read buffer was changed into an iovec to avoid doing
too many binary concatenations and allocations.
Decompression happens transparently: when decoding gzip,
the content-encoding header is removed (we only decode
when "gzip" is the only encoding so nothing remains).
We always add a content_decoded key to the Req object.
This key contains a list of codings that were decoded,
in the reverse order in which they were. Currently it
can only be empty or contain <<"gzip">> but future
improvements or user handlers may see it contain more
values.
The option to disable decompression was renamed to
decompress_enabled and defaults to true.
It is no longer possible to enable/disable decompression
in the middle of reading the body: this ensures that the
data we pass forward is always valid.
Various smaller improvements were made to the code,
tests and manual pages.
