Consider removing parquetexporter

[atoulme]

Component(s)

exporter/parquet

Describe the issue you're reporting

I am the original author of the parquetexporter, and I think it needs to be removed.

Apache Parquet is a project defining a columnar data format that allows to work well with big data and S3-type storage.

This exporter was meant to be used to export data to Parquet files, but it's ambiguous how to write those files to S3. The awss3exporter would be a preferred approach to writing data. It is possible an encoder using Parquet will be applied moving forward, allowing easy marshaling and unmarshaling.

As is, the exporter is misleading ; it offers the hope for Parquet support but does little to get it done.

There was work from me on delivering a Parquet schema based off our protobuf schema, but it faltered. It appears the Otel Arrow approach is superior there and we should use this move forward.

In any case, I think it's time to remove this exporter altogether. No work has taken place on it in the last year.