Serialize a tree to HTML¶

Render a tree back to conformant HTML and control the result: pick the escape Formatter, choose an Indent layout, stream the output in bounded chunks, and encode to bytes.

Serialize with control¶

html and inner_html are the default WHATWG-conformant forms (outer and children-only). serialize() adds control through a single Html configuration object: its formatter field selects the escaping through Formatter, and its layout field selects the whitespace. The default layout of None gives the compact form; an Indent (an int for that many spaces, or a string used verbatim) switches to a pretty form that adds whitespace and so does not preserve meaning. encode() is the same but returns bytes, with the target encoding as its first argument:

import turbohtml
from turbohtml import Formatter, Html, Indent

card = turbohtml.parse("<div><p>café &amp; co</p></div>").select_one("div")
print(card.inner_html)
print(card.serialize(Html(formatter=Formatter.NAMED_ENTITIES)))
print(card.serialize(Html(layout=Indent(2))))
print(card.encode("ascii", Html(formatter=Formatter.NAMED_ENTITIES)))

<p>café &amp; co</p>
<div><p>caf&eacute; &amp; co</p></div>
<div>
  <p>
    café &amp; co
  </p>
</div>
b'<div><p>caf&eacute; &amp; co</p></div>'

Normalize attributes and encoding¶

Two more Html fields normalize the output without touching the tree, and compose with any formatter or layout. sort_attributes emits each start tag’s attributes in ascending name order, so two serializations of equal trees diff cleanly:

import turbohtml
from turbohtml import Html

node = turbohtml.parse("<p id=main class=lead data-x=1>hi</p>").select_one("p")
print(node.serialize(Html(sort_attributes=True)))

<p class="lead" data-x="1" id="main">hi</p>

meta_charset makes the document <head> declare the output encoding: an existing <meta charset> (or <meta http-equiv="content-type">) is normalized in place, and a head that declares none gets a <meta charset> injected as its first child, never a duplicate. serialize declares utf-8 (the encoding of the returned str), while encode declares the encoding it writes:

import turbohtml
from turbohtml import Html

doc = turbohtml.parse("<title>Hi</title>")
print(doc.serialize(Html(meta_charset=True)))
print(doc.encode("iso-8859-1", Html(meta_charset=True)))

<html><head><meta charset="utf-8"><title>Hi</title></head><body></body></html>
b'<html><head><meta charset="iso-8859-1"><title>Hi</title></head><body></body></html>'