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https://issues.apache.org/jira/browse/ARROW-18275?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17633977#comment-17633977
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Weston Pace commented on ARROW-18275:
-------------------------------------

{quote}
1. Custom formats can tell pa.dataset.dataset to use the correct FileFormat
based on the filename / extension (instead of requiring the user to pass a
custom FileFormat subclass instance every time).
{quote}

We might be able to do this by creating a "ExtensionGuessingFileFormat" which 
could be the new default.  It would construct the appropriate formats as needed 
and delegate work to them.  It could even perhaps take a map from extension to 
format.  This way, if users did need to fine-tune the formats (e.g. specify a 
custom delimiter for CSV) it would still be possible.



> [Python] Allow custom reader/writer implementation for arrow dataset 
> read/write path
> ------------------------------------------------------------------------------------
>
>                 Key: ARROW-18275
>                 URL: https://issues.apache.org/jira/browse/ARROW-18275
>             Project: Apache Arrow
>          Issue Type: New Feature
>          Components: Python
>    Affects Versions: 10.0.0
>            Reporter: Chang She
>            Priority: Major
>              Labels: Python
>
> We're implementing a "versionable" data format where the read/write path has 
> some metadata handling which we currently can't plug into the native pyarrow 
> write_dataset and pa.dataset.dataset mechanism.
> What we've done currently is have our own `lance.write_dataset` and 
> `lance.dataset` interfaces which knows about the versioning. And if you use 
> the native arrow ones, it reads/writes an unversioned dataset.
> It would be great if:
> 1. the arrow interfaces provided a way for custom data formats to provide 
> their own Arrow compliant reader/writer implementations, so we can delete our 
> custom interface and stick with native pyarrow interface.
> 2. the pyarrow interface can support custom kwargs like "version=5" or 
> "as_of=<timestamp>" or "version='latest'"
> for reference, this is what our custom C++ dataset implementation looks like: 
> https://github.com/eto-ai/lance/blob/main/cpp/include/lance/arrow/dataset.h



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