Thanks Antoine. Do we need to hold a vote to adopt the C API? I will see if I can review the C++ implementation prior to leaving for ~1 week of vacation next Tuesday
On Thu, Nov 7, 2019 at 1:24 PM Antoine Pitrou <anto...@python.org> wrote: > > > Hello, > > The C data interface spec was updated following a suggestion > by Wes and Uwe: > https://github.com/apache/arrow/blob/3173f88dfa32ce3296a121b032f351e089888601/docs/source/format/CDataInterface.rst > > The metadata encoding was changed. It does not use JSON anymore > but a very simple binary encoding. Quoting the spec: > > This string is not null-terminated but follows a specific format:: > > int32: number of key/value pairs (noted N below) > int32: byte length of key 0 > key 0 (not null-terminated) > int32: byte length of value 0 > value 0 (not null-terminated) > ... > int32: byte length of key N - 1 > key N - 1 (not null-terminated) > int32: byte length of value N - 1 > value N - 1 (not null-terminated) > > For example, the metadata ``[('key1', 'value1')]`` is encoded as:: > > \x01\x00\x00\x00\x04\x00\x00\x00key1\x06\x00\x00\x00value1 > > > The C++ draft implementation now supports metadata exporting and importing: > https://github.com/apache/arrow/pull/5608 > > Regards > > Antoine.
