Steve Dower | Musings and Mutterings

Async/await in Python

Those who follow the development of C# and VB probably know about the recently added Async and Await keywords, which turn code like this:

int AccessTheWeb() {
    int result;
    Thread thread = new Thread((() => {
        HttpClient client = new HttpClient();
        string urlContents = client.GetString("");
        result = urlContents.Length;
    return result;

Into code like this:

async Task<int> AccessTheWebAsync()
    HttpClient client = new HttpClient();
    Task<string> getStringTask = client.GetStringAsync("");
    string urlContents = await getStringTask;
    return urlContents.Length;

For the last week or two, an intense discussion has been occurring on the python-ideas mailing list about asynchronous APIs, to which I’ve been contributing/supporting an approach similar to async/await. Since I wrote a 5000 word essay this week on the topic, I’m going to call that my post.

Read: Asynchronous API for Python.