Learning Python Networking - Second Edition

Downloading files with aiohttp

First, we must import the modules we need to make our HTTP requests asynchronous. All asynchronous functions will need to have the async keyword in the function definition.

We will start by defining our download_file function, which will take two parameters: the first parameter is the URL for downloading the image, and the second parameter is called parts, which is the number of parallel requests we want to make to the server.

To make our asynchronous program faster, this is how our script is going to work:

1. We are going to make a head request to the file URL with the aiohttp.ClientSession().head(url) method.
2. We are going to get the value of the Content-Length header for getting the file size with the size = ...