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This is a pre-production deployment of Warehouse. Changes made here affect the production instance of PyPI (
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Download URLs using a compressed disk cache and a random throttling interval.

Project Description
Each Downloader maintains an sqlite3-based disk cache that utilizes zlib

compression. Network requests are only made if the cached version of the resource has an age larger or equal to the stale_after value provided by the programmer.

Between network requests a throttling interval needs to elapse. This throttling interval is randomly chosen, but lies within the throttle_bounds defined by the programmer.

HTML resources can be parsed using lxml and in this case an lxml ElementTree is returned instead of a file object, with the links rewritten to be absolute in order to facilitate following them. The parsing is done leniently in order to not fail when invalid HTML is encountered.

The programmer can also supply a function that decides whether the server has banned the client (possibly by examining the returned resource). In this case an exception will be raised.

Downloader’s features make it ideal for writing scrapers, as it can keep its network footprint small (due to the cache) and irregular (due to the random throttling interval).

Release History

Release History

History Node


History Node


This version
History Node


Download Files

Download Files

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File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
downloader-0.95.win32.exe (202.3 kB) Copy SHA256 Checksum SHA256 any Windows Installer Sep 24, 2014 (6.6 kB) Copy SHA256 Checksum SHA256 Source Sep 24, 2014

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