The most idiomatic option seems to be a virtual base class with derived
classes as required:
```
class CodecOptions {
public:
virtual ~CodecOptions() = default;
int compression_level;
};
class ZlibCodecOptions : public CodecOptions {
public:
~CodecOptions() = default;
int window_bits;
};
class Codec {
public:
static Result<std::unique_ptr<Codec>> Create(
Compression::type codec, const CodecOptions* = nullptr);
};
```
Le 23/04/2023 à 16:50, Gang Wu a écrit :
It is a good idea to extend the Codec factory to offer more options.
However, I don't think adding
a `window_bits` parameter as `compression_level` is a good approach as it
does not apply to
some codecs.
IMO, the proposed new `Codec::Options` can be as simple as a
std::map<std::string, std::string>.
To avoid misuse, we need to formalize all acceptable keys somewhere and
specific codecs only
need to deal with config keys that they know.
WDYT?
Best,
Gang
On Sun, Apr 23, 2023 at 5:38 PM Yang, Yang10 <yang10.y...@intel.com> wrote:
Hi,
As discussed in this issue: https://github.com/apache/arrow/issues/35287,
currently Arrow only supports one parameter: compression_level to be
customized. We would like to make more compression parameters (such as
window_bits) customizable when creating the Codec, given the variety of
usage scenarios. As suggested by @kou, we may introduce a new options class
such as Codec::Options to make the structure clear and easy to extend. But
it may take some effort as this is more like a code structure refactor.
Passing a parameter directly is another approach, easy to implement but may
be hard to extend. So we would like some further discussion here. If you
have any suggestion or comments, please share them on above issue or here.
Thanks!
Best,
Yang
