Get keys from redis using zrange and generate output csv file

get_all_keys_redis_using_zrange.py

import json
from timeit import default_timer as timer
import csv

from redis import ConnectionPool, Redis


__REDIS_HOST = ''
__PAGE_SIZE = 500
__OUTPUT_FILE_NAME = ''
__ZKEY_NAME = ''


def create_cache_connection():
    connection_pool = ConnectionPool(
        host=__REDIS_HOST,
        port=6379,
    )
    return Redis(connection_pool=connection_pool)


def create_csv(output_file, rows):
    with open(output_file, 'a') as file:
        writer = csv.writer(file, delimiter='\n')
        writer.writerow(rows)


def time_in_minutes(seconds):
    return "%.2f" % (seconds / 60)


def main():
    print("Starting job")
    start_time_job = timer()
    total_keys = 0
    cache = create_cache_connection()

    page = 0
    should_continue = True
    while should_continue:

        start = page * __PAGE_SIZE
        stop = start + __PAGE_SIZE - 1

        keys = cache.zrange(__ZKEY_NAME, start, stop)
        print(f"\nGetting {len(keys)} keys from page {page}")
        if len(keys):
            keys_id = []
            for item in keys:
                id = json.loads(item).get('key_name')
                keys_id.append(id)

            total_keys =  total_keys + len(keys)
            print(f"Saving {len(keys_id)} keys on csv file")
            create_csv(__OUTPUT_FILE_NAME, keys_id)

            page = page + 1 
        else:
            should_continue = False

    cache.close()

    time_elapsed = time_in_minutes(timer() - start_time_job)
    print(f"\n{total_keys} keys processed in {time_elapsed} minutes\n")


if __name__ == "__main__":
    main()