A high-performance event-driven HTTP client+server for Clojure
[http-kit "2.4.0"] ; Stable, published by contributors, see CHANGELOG for details [http-kit "2.1.19"] ; Legacy, published by @shenfeng
http-kit's author (@shenfeng) unfortunately hasn't had much time to maintain http-kit recently. To help out I'll be doing basic issue triage, accepting minor/obvious PRs, etc.
A big thank you to the current contributors for keeping the project going! Additional contributors welcome: please ping me if you'd be interested in lending a hand.
See the (unmaintained, outdated) project website for original documentation, examples, benchmarks, etc.
High performance: Using an event-driven architecture like Nginx, HTTP-kit is very, very fast. It comfortably handles tens of thousands of requests/sec on even midrange hardware. Here is another test about how it stacks up with others.
High concurrency: It's not only fast, but efficient! Each connection costs nothing but a few kB of memory. RAM usage grows O(n) with connections.
Clean, simple, small: Written from the ground-up to be lean, the entire client/server is available as a single ~90kB JAR with zero dependencies and ~3k lines of (mostly Java) code.
Sync or async: Synchronous is simple. Asynchronous is fast & flexible. With HTTP Kit you get the best of both with a simple API that lets you mix & match to best fit your use case.
Enabling client SNI support (DISABLED BY DEFAULT)
To retain backwards-compatibility with JVMs < 8, http-kit client's SNI support is DISABLED by default.
Common cause of:
javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure
This default may be changed in a future breaking release. In the meantime, manually enabling support is easy:
(:require [org.httpkit.sni-client :as sni-client]) ; Needs Java >= 8, http-kit >= 2.4.0-alpha6 ;; Change default client for your whole application: (alter-var-root #'org.httpkit.client/*default-client* (fn [_] sni-client/default-client)) ;; or temporarily change default client for a particular thread context: (binding [org.httpkit.client/*default-client* sni-client/default-client] <...>)
org.httpkit.client/*default-client* docstring for more details.
Hacker friendly: zero dependencies, written from the ground-up with only ~3.5k lines of code (including java), clean and tidy.
# Modify as you want, unit tests back you up: lein test # May be useful (more info), see `server_test.clj`: ./scripts/start_test_server # Some numbers on how fast can http-kit's client can run: lein test :benchmark