clj-fast-html

clj-fast-html is a Clojure library designed for fast and efficient HTML generation.

Usage

You can find the latest version on Clojars:

Example:

Here is an example of how to use clj-fast-html to generate an HTML string:

(clj-fast-html.core/to-html-string
 [[:html/raw "<!DOCTYPE html>"]
  [:html
   [:head
    [:title "Title"]]
   [:body
    [:h1#id.class1.class2 "Header"]
    [:p {:style {:color "red"}} "text"]
    [:p {:class ["class3" "class4"]} "text"]
    [:p {:class "class3 class4"} "text"]
    [:dialog {:open true} "text"]
    [:span {:href (clj-fast-html.core/escape "' onmouseover='alert(1)")}]
    [:span (clj-fast-html.core/escape "<p onmouseover='alert(1)'></p>")]
    (mapv
     (fn [x]
       [:span x])
     [1 2 3 4])]]])

<!DOCTYPE html>
<html>
  <head>
    <title>Title</title>
  </head>
  <body>
    <h1 id="id" class="class1 class2">Header</h1>
    <p style="color:red">text</p>
    <p class="class3 class4">text</p>
    <p class="class3 class4">text</p>
    <dialog open>text</dialog>
    <span href="&#39; onmouseover=&#39;alert(1)"></span>
    <span>&lt;p onmouseover=&#39;alert(1)&#39;&gt;&lt;/p&gt;</span>
    <span>1</span>
    <span>2</span>
    <span>3</span>
    <span>4</span>
  </body>
</html>

Benchmark

The performance of clj-fast-html is benchmarked against other popular HTML generation libraries. Below are the benchmark results for generating the Clojure home page

Single Thread

Library	Average (ns)	%
clj-fast-html (latest)	39434.940 ns/op	0%
Hiccup (2.0.0-RC3)	306147.614 ns/op	676.34%
Hiccup (2.0.0-RC1)	666406.325 ns/op	1589.89%

Multithread

Library	Average (μs)	%
clj-fast-html (latest)	176.198 μs/op	0%
Hiccup (2.0.0-RC3)	1332.627 μs/op	656.32%
Hiccup (2.0.0-RC1)	2041.248 μs/op	1058.5%

To run the benchmark yourself, use the following command:

make bench