Converter for HTML fragments with mathematics using mathjax-node
mathjax-node-page 
This Node.js module builds on mathjax-node and provides processing of larger content fragments
Installation
Use
npm install mathjax-node-page
to install mathjax-node-page and its dependencies.
Usage
mathjax-node-page exports mjpage which expects four parameters:
mjpage(input, mjpageConfig, mjnodeConfig, callback)
Where input is a string with HTML, pageConfig specifies page-wide options, and mjnodeConfig expects mathjax-node configuration options.
The defaults for pageConfig are
-- -------------------- ---- -------
-
------- ---------- ------ ------------- -- ---------- ---- -- -------------- -- ---
------- --- -- ------ -------- --- ------ ------- ------ ------ -- -----
---- --- -- ------------- ------- --- --- -------------- --- ----------
------ --- -- ------------- ------- --- ----- -------------- --- ------------
-------------- ------ -- ----- ------------- --------- --- ------ ---
--------- ------ -- ------ -------------- ------- -- ---- --------
---------- ----- -- ---------- ------- ------ --- ------ -- -----
------ ---- -- -- ------------- -------
---------------- ------ -- ---------- ------- ------------- ----- --- ------
-------------- ----- -- ---------- ------- ----- -------- --- ----- -- --- -------
------------------- ------ -- ---------- ------- ------- ---------- --- ----- -- --- ----- -----
----------- --- -- - ----------- ------ -- --- ------- ----------
-------- ---------------------------------------------------------------------- -- --- ------- ---- -- --- --- --- ---- ------
-------- -- -- ------- ------- -------------- --- ------------------------
-and where mjnodeConfig represents mathjax-node configuration options, the defaults are.
-- -------------------- ---- ------- - --- -- -- ------- -- ------ ------ ---- -- ----- -- ---- --------- --- --- --- ------------ --- ---- ------------- ----- -- --- ------ --- ----- -- --- ------- --------------- ------ -- --- ------ ------ --- --- ---------- ------ -------- -- ----- ------ ----- ----------- ------ -- -- ------------- ---------------- ------- -- -- ----- -- ----- ----- --- -- --- ---- -- ------- ----- ------ -- -------- ---- ------- ---- ------ -- -------- --- --- ---- ------- ---- ------ -- -------- --- ------- ---- ------ -- -------- --- ------- ---------- ----- -- --- ------ ----------- -- ------- -------- -- - ----- -- -- ------ ------- ------ ---------- ------- -
Advanced usage
mathjax-node customization
mathjax-node-page exports init function that allows you to pass in a custom mathjax-node (for example, mathjax-node-svg2png).
const mjnode = require('mathjax-node-svg2png');
mjpage.init(mjnode);If your custom mathjax-node provides new output options, you can add them by calling addOutput. As a second parameter, you can pass custom output handler, which is a function that modifies a DOM element with the conversion result. The default output handler behavior is to write contents to wrapper.innerHTML.
mjpage.addOutput('png', (wrapper, data) => {
wrapper.innerHTML = `<img src="${data}">`;
});
// ...now you can use standard mathjax-node-page APIReset to default mathjax-node behavior by calling init with empty parameters. Ensure that all your current mathjax-node-page tasks have been completed before calling it.
mjpage.init(); // reset back to default mathjax-node
Events
mjpage runs jobs which inherit EventEmitter and provide the following event hooks.
Add the corresponding event handlers to manipulate the input/output and DOM before/after conversion.
All the event handlers are destroyed when job ends to prevent memory leaks.
Formula conversion events
beforeConversion->handler(parsedFormula): runs before individual formula conversion started, but after initial DOM processing. All the formulas are wrapped in<script type="...">tags, where@typeis one of the following:
const scripts = document.querySelectorAll(`
script[type="math/TeX"],
script[type="math/inline-TeX"],
script[type="math/AsciiMath"],
script[type="math/MathML"],
script[type="math/MathML-block"]`
);afterConersion->handler(parsedFormula): runs after individual formula conversion completed and DOM was changed. Formula DOM node is a<span class="mjpage...">wrapper whose contents are the conversion result.
All formula conversion events pass ParsedFormula instance to the event handler.
-- -------------------- ---- -------
-
--- -- ----- -- ------- -- --- ----
------ -- ------ --- --- -------- --------- -- --- ---- ---- --- ---- --- ---- -----
----- -- --- ---- ---- --- ------- --------- ------ ------ --- ----- -----------
-------------- -- --- ------ -------
------------- -- --- ------ ------- ------ ----- -------------
-------------- -- --- --------- ------- ------ ---- ------------ ------- --------- --- --------------------------- -- --- --- --------- ------- ------
------------ -- --- --------- ------- ------ ----- ------
-Page conversion events
beforeSerialiation->handler(document, css): runs when converted page DOM was prepared immediately before serialization. Use to manipulate resulting page DOM. The event handler receivesdocumentnode (jsdom) and pagecss.
mjpage function callback receives result after the DOM serialization.
Example
-- -------------------- ---- -------
------------- -
------- -------
-- -
---- ----
-- ---------------- -
-- ------ -- ---- ----- ------
--
---------------------- ----------------------- -
-- ---------- ------ ------ --- --- -- ---- ----
-- --- ----------- -- ------------- ------ -----
---CLI
mathjax-node-page installs a CLI tool. Run mjpage to print usage instructions.
Example
const mjpage = require('../lib/main.js').mjpage;
const fs = require('fs');
const input = fs.readFileSync('input.html');
mjpage(input, {format: ["TeX"]}, {svg: true}, function(output) {
console.log(output); // resulting HTML string
});Tips
mathjax-node-pageis intended to work with HTML pages and it uses DOM parser while extracting formulas from the document. If your page is not HTML, make sure you escape < (<) and > (>) before usage. This test contains an example.
HomePage
https://github.com/roman-spiridonov/mathjax-node-page#readme
Repository
git+https://github.com/roman-spiridonov/mathjax-node-page.git
来源：JavaScript中文网 ，转载请注明来源 https://www.javascriptcn.com/post/6005606781e8991b448de8aa