Parse HTML text into a tree of elements with selectors
Htmlparser is a listed LuaRock. Install using LuaRocks: luarocks install htmlparser
Htmlparser depends on Lua 5.1-5.4 or LuaJIT, which provides 5.1-compatible API/ABI. To be able to run the tests, lunitx also comes along as a LuaRock
Start off with
local htmlparser = require("htmlparser")Then, parse some html:
local root = htmlparser.parse(htmlstring)Optionally, you can pass loop-limit value (integer). This value means the deepness of the tree, after which parser will give up. Default value is 1000.
Also, global variable htmlparser_looplimit is supported (while this optional argument takes priority over global value)
The input to parse may be the contents of a complete html document, or any valid html snippet, as long as all tags are correctly opened and closed. Now, find specific contained elements by selecting:
local elements = root:select(selectorstring)Or in shorthand:
local elements = root(selectorstring)This wil return a list of elements, all of which are of the same type as the root element, and thus support selecting as well, if ever needed:
for _,e in ipairs(elements) do
print(e.name)
local subs = e(subselectorstring)
for _,sub in ipairs(subs) do
print("", sub.name)
end
endThe root element is a container for the top level elements in the parsed text, i.e. the <html> element in a parsed html document would be a child of the returned root element.
Supported selectors are a subset of jQuery's selectors:
"*"all contained elements"element"elements with the given tagname"#id"elements with the given id attribute value".class"elements with the given classname in the class attribute"[attribute]"elements with an attribute of the given name"[attribute='value']"equals: elements with the given value for the given attribute"[attribute!='value']"not equals: elements without the given attribute, or having the attribute, but with a different value"[attribute|='value']"prefix: attribute's value is given value, or starts with given value, followed by a hyphen (-)"[attribute*='value']"contains: attribute's value contains given value"[attribute~='value']"word: attribute's value is a space-separated token, where one of the tokens is the given value"[attribute^='value']"starts with: attribute's value starts with given value"[attribute$='value']"ends with: attribute's value ends with given value":not(selectorstring)"elements not selected by given selector string"ancestor descendant"elements selected by thedescendantselector string, that are a descendant of any element selected by theancestorselector string"parent > child"elements selected by thechildselector string, that are a child element of any element selected by theparentselector string
Selectors can be combined; e.g. ".class:not([attribute]) element.class"
All tree elements provide, apart from :select and (), the following accessors:
.namethe element's tagname.attributesa table with keys and values for the element's attributes;{}if none.idthe value of the element's id attribute;nilif not present.classesan array with the classes listed in element's class attribute;{}if none:getcontent()the raw text between the opening and closing tags of the element;""if none.nodesan array with the element's child elements,{}if none.parentthe element that contains this element;root.parentisnil
.indexsequence number of elements in order of appearance; root index is0:gettext()the complete element text, starting with"<tagname"and ending with"/>"or"</tagname>".levelhow deep the element is in the tree; root level is0.rootthe root element of the tree;root.rootisroot.deepernodesa Set containing all elements in the tree beneath this element, including this element's.nodes;{}if none.deeperelementsa table with a key for each distinct tagname in.deepernodes, containing a Set of all deeper element nodes with that name;{}if none.deeperattributesas.deeperelements, but keyed on attribute name.deeperidsas.deeperelements, but keyed on id value.deeperclassesas.deeperelements, but keyed on class name
- Attribute values in selector strings cannot contain any spaces
- The spaces before and after the
>in aparent > childrelation are mandatory <!elements (including doctype, comments, and CDATA) are not parsed; markup within CDATA is not escaped- Textnodes are no separate tree elements; in
local root = htmlparser.parse("<p>line1<br />line2</p>"),root.nodes[1]:getcontent()is"line1<br />line2", whileroot.nodes[1].nodes[1].nameis"br" - No start or end tags are implied when omitted. Only the void elements should not have an end tag
- No validation is done for tag or attribute names or nesting of element types. The list of void elements is in fact the only part specific to HTML
See ./doc/sample.lua
See ./tst/init.lua
LGPL+; see ./doc/LICENSE