iterate_gzipped_s3_file.py

#!/usr/bin/env python3

import boto3
import gzip
import io
import sys
import tempfile


BUCKET = 'SOME_BUCKET'
PATH = 'SOME_PATH'

# also see http://pandas.pydata.org/pandas-docs/stable/generated/pandas.read_csv.html - 'compression' setting
def iterate_gz_file(filename='file_name'):
    s3 = boto3.resource('s3')
    with tempfile.NamedTemporaryFile() as tmp_file:
        s3.meta.client.download_file(LOG_BUCKET, '%s/%s' % (LOG_PATH, filename) , tmp_file.name)
        with io.TextIOWrapper(io.BufferedReader(gzip.open(tmp_file.name))) as file:
            for line in file:
                print(line)


if __name__ == '__main__':
    iterate_gz_file()