#!/usr/bin/env python

import os
import logging
from shutil import copyfileobj

logging.basicConfig(level=logging.DEBUG)
log = logging.getLogger()
# Reduce the logging level of botocore and boto3
logging.getLogger('botocore').setLevel(logging.WARNING)
logging.getLogger('boto3').setLevel(logging.WARNING)


from django.conf import settings
settings.configure()

import boto3
from storages.backends.s3boto3 import S3Boto3Storage


def mktestfile(filename):
    """Generates a ten megabyte text file with an incrementing counter."""
    desired_size = 10 * (2 ** 20)
    num_lines = desired_size // 64
    with open(filename, 'w') as f:
        for i in range(num_lines):
            # each line is 64 characters long, with leading whitespace
            # and the counter at the end. using 'sort -c' can confirm it's
            # in numeric order.
            f.write('%63d\n' % (i + 1))


FN = 'test-file.txt'
BUCKET = 'kx-tom-misc-test-bucket'
if not os.path.exists(FN):
    log.info("Creating test file.")
    mktestfile(FN)

s3_storage = S3Boto3Storage(
    bucket=BUCKET
)

original_size = os.stat(FN).st_size
log.info("Size of '%s' is %d bytes. (%d megabytes)", FN, original_size, original_size // 2**20)
dest_file = s3_storage.open(FN, 'wb')
with open(FN, 'rb') as source_file:
    CHUNK_SIZE = 2 ** 20  # one megabyte
    log.info("Writing to %r in chunks of %d bytes (%d megabyte).", dest_file, CHUNK_SIZE, CHUNK_SIZE // 2**20)
    copyfileobj(source_file, dest_file, length=2**20)
dest_file.close()
log.info('Upload complete, checking size of file in S3 Bucket')
s3_object_size = boto3.resource('s3').Bucket(BUCKET).Object(FN).content_length
log.info("Size of 's3://%s/%s' is %d bytes. (%d megabytes)",
    BUCKET, FN, s3_object_size, s3_object_size // 2**20)