#!/usr/bin/env python3
"""
Yank data from Swift and do [something] with it.
"""

import json
import lzma
import os
import sys

from multiprocessing import Pool

import swiftclient


class ObjectStorage:
    def __init__(self, swift_config, container, prefix=None):
        self.swift = swiftclient.client.Connection(**swift_config)
        self.container = container
        self.prefix = prefix

    def list_container(self):
        listing = self.swift.get_container(self.container,
                                           prefix=self.prefix,
                                           full_listing=True)
        return [item["name"] for item in listing[1]]

    def process(self, name):
        compressed = self.swift.get_object(self.container, name)[1]
        raw = lzma.decompress(compressed)
        data = json.loads(raw.decode("utf-8"))
        # do something with the data ...


if __name__ == "__main__":
    swift_config = {
        "auth_version": 2,
        "authurl": os.getenv("OS_AUTH_URL"),
        "user": os.getenv("OS_USERNAME"),
        "key": os.getenv("OS_PASSWORD"),
        "tenant_name": os.getenv("OS_TENANT_NAME")
    }

    if len(sys.argv) != 4:
        print("args: workers container object-name-prefix")
        sys.exit(1)

    workers = int(sys.argv[1])
    container = sys.argv[2]
    prefix = sys.argv[3]

    os = ObjectStorage(swift_config, container, prefix)

    names = os.list_container()

    with Pool(workers) as pool:
        pool.map(os.process, names)