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transform_archive(user, mode \\ :tsv)

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transform_archive(binary(), :tsv) :: :ok

Transform downloaded raw JSON data and create a TSV file archive for a Lastfm user.



The function only transforms downloaded archive data on local filesystem. It does not fetch data from Lastfm, which can be done via archive/2, archive/3.

The TSV files are created on a yearly basis and stored in gzip compressed format. They are stored in a tsv directory within either the default ./lastfm_data/ or the directory specified in config/config.exs (:lastfm_archive, :data_dir).