myhtml
MyHTML
Fast HTML5 Parser (Crystal binding for awesome lexborisov's myhtml and Modest). This shard used in production to parse millions of pages per day, very stable and fast.
Installation
Add this to your application's shard.yml
:
dependencies:
myhtml:
github: kostya/myhtml
And run shards install
Usage example
require "myhtml"
html = <<-HTML
<html>
<body>
<div id="t1" class="red">
<a href="/#">O_o</a>
</div>
<div id="t2"></div>
</body>
</html>
HTML
myhtml = Myhtml::Parser.new(html)
myhtml.nodes(:div).each do |node|
id = node.attribute_by("id")
if first_link = node.scope.nodes(:a).first?
href = first_link.attribute_by("href")
link_text = first_link.inner_text
puts "div with id #{id} have link [#{link_text}](#{href})"
else
puts "div with id #{id} have no links"
end
end
# Output:
# div with id t1 have link [O_o](/#)
# div with id t2 have no links
Css selectors example
require "myhtml"
html = <<-HTML
<html>
<body>
<table id="t1">
<tr><td>Hello</td></tr>
</table>
<table id="t2">
<tr><td>123</td><td>other</td></tr>
<tr><td>foo</td><td>columns</td></tr>
<tr><td>bar</td><td>are</td></tr>
<tr><td>xyz</td><td>ignored</td></tr>
</table>
</body>
</html>
HTML
myhtml = Myhtml::Parser.new(html)
p myhtml.css("#t2 tr td:first-child").map(&.inner_text).to_a
# => ["123", "foo", "bar", "xyz"]
p myhtml.css("#t2 tr td:first-child").map(&.to_html).to_a
# => ["<td>123</td>", "<td>foo</td>", "<td>bar</td>", "<td>xyz</td>"]
More Examples
Development Setup:
git clone https://github.com/kostya/myhtml.git
cd myhtml
make
crystal spec
Benchmark
Parse 1000 times google page, and 1000 times css select. myhtml-program, crystagiri-program, nokogiri-program
| Lang | Shard | Lib | Parse time, s | Css time, s | Memory, MiB | | -------- | ---------- | --------------- | ------------- | ----------- | ----------- | | Crystal | myhtml | myhtml(+modest) | 3.04 | 0.32 | 12.9 | | Crystal | Crystagiri | libxml2 | 9.63 | 20.3 | 29.3 | | Ruby 2.2 | Nokogiri | libxml2 | 28.14 | 55.69 | 124.5 |