Async HTTP

This project requests one JSON object from jsonplaceholder.typicode.com. It requires network access and the remote response may change.

Manifest#

;; Spork Project Manifest
;; See https://spork.sh/docs/reference/tooling/ for manifest documentation

{:name "async"
 :version "0.1.0"

 ;; Dependencies (pip-style specifications)
 :dependencies ["aiohttp>=3.10,<4"]

 ;; Source code locations
 :source-paths ["src"]

 ;; Entry point for 'spork run'
 :main "async.core:main"}

Source#

;; async - Core module
(ns async.core
  (:import [aiohttp] [asyncio]))

;; Define an asynchronous function with the ^async metadata
(defn ^async fetch-data [^str url]
  (async-with [session (aiohttp.ClientSession)]
    (async-with [resp (session.get url)]
      (await (resp.json)))))

;; Run it on the event loop
(defn main []
  (let [url "https://jsonplaceholder.typicode.com/todos/1"
        data (asyncio.run (fetch-data url))]
    (print "Received data:")
    (print data)))

Run it from the project directory:

spork sync
spork run

The aiohttp package supplies Python asynchronous context managers and coroutines; Spork’s async-with and await forms compile directly to their Python equivalents. See async and generators.