filter_items.py

# MIT License
#
# Copyright (c) 2018 Evgeny Medvedev, evge.medvedev@gmail.com
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# SOFTWARE.


import argparse
import json

from ethereumetl.file_utils import smart_open

parser = argparse.ArgumentParser(description='Extracts a single column from a given csv file.')
parser.add_argument('-i', '--input', default='-', type=str, help='The input file. If not specified stdin is used.')
parser.add_argument('-o', '--output', default='-', type=str, help='The output file. If not specified stdout is used.')
parser.add_argument('-p', '--predicate', required=True, type=str,
                    help='Predicate in Python code e.g. "item[\'is_erc20\']".')

args = parser.parse_args()

# TODO: Add support for CSV
with smart_open(args.input, 'r') as input_file, smart_open(args.output, 'w') as output_file:
    for line in input_file:
        item = json.loads(line)
        if eval(args.predicate, globals(), {'item': item}):
            output_file.write(json.dumps(item) + '\n')