Convert {parquet | orc} to json and orc to parquet

converter.py

#! /usr/bin/env python
import pandas as pd
import argparse
import os
import pyarrow.orc as orc

# usage: ./converter.py --help

CONVERTERS = ['parquet2json',  'orc2json', 'orc2parquet']

def parquet2json(filename):
    df = pd.read_parquet(f'{filename}.parquet')
    df.to_json(f'{filename}.json', orient='records')
    
    
def orc2json(filename):
    data = orc.ORCFile(f'{filename}.orc')
    df = data.read().to_pandas()
    df.to_json(f'{filename}.json', orient='records')
    
    
def orc2parquet(filename):
    data = orc.ORCFile(f'{filename}.orc')
    df = data.read().to_pandas()
    df.to_parquet(f'{filename}.parquet', compression='gzip')
    
    
def convert(args): 
    converter = args.converter
    filename = os.path.splitext(args.sourcefile)[0]
    
    switcher = {
        "parquet2json": parquet2json,
        "orc2json": orc2json,
        "orc2parquet": orc2parquet
    }
    
    converter_func = switcher.get(converter)
    converter_func(filename)
    
    
def main():
    parser = argparse.ArgumentParser(description="Convert parquet to json | ocr to json | orc to parquet.")
    parser.add_argument("converter", choices=CONVERTERS)
    parser.add_argument("sourcefile")
    parser.set_defaults(func=convert)
    args = parser.parse_args()
    args.func(args)
    
    
if __name__ == "__main__":
    main()