Mammoth .docx to HTML converter

Mammoth is designed to convert .docx documents, such as those created by Microsoft Word, and convert them to HTML. Mammoth aims to produce simple and clean HTML by using semantic information in the document, and ignoring other details. For instance, Mammoth converts any paragraph with the style Heading1 to h1 elements, rather than attempting to exactly copy the styling (font, text size, colour, etc.) of the heading.

There's a large mismatch between the structure used by .docx and the structure of HTML, meaning that the conversion is unlikely to be perfect for more complicated documents. Mammoth works best if you only use styles to semantically mark up your document.

Installation

npm install mammoth

Usage

To convert an existing .docx file to HTML, use mammoth.convertToHtml:

var mammoth = require("mammoth");

mammoth.convertToHtml({path: "path/to/document.docx"})
    .then(function(result){
        var html = result.value; // The generated HTML
        var messages = result.messages; // Any messages, such as warnings during conversion
    });

By default, Mammoth maps some common .docx styles to HTML elements. For instance, a paragraph with the style Heading1 is converted to a h1 element. You can pass in a custom map for styles by passing an options object as a second argument to convertToHtml:

var mammoth = require("mammoth");
var style = mammoth.style;

var options = {
    styleMap: [
        style("p.Heading1 => h1"),
        style("p.Heading2 => h2")
    ]
};
mammoth.convertToHtml({path: "path/to/document.docx"}, options);

To extend the standard style map:

var mammoth = require("mammoth");
var style = mammoth.style;

var customStyles = [
    style("p.AsideHeading => div.aside > h2:fresh"),
    style("p.AsideText => div.aside > p:fresh")
];

var options = {
    styleMap: customStyles.concat(mammoth.standardOptions.styleMap)
};
mammoth.convertToHtml({path: "path/to/document.docx"}, options);

Writing styles

A style has two parts:

• On the left, before the arrow, is the document element matcher.
• On the right, after the arrow, is the HTML path.

When converting each paragraph, Mammoth finds the first style where the document element matcher matches the current paragraph. Mammoth then ensures the HTML path is satisfied.

Freshness

When writing styles, it's helpful to understand Mammoth's notion of freshness. When generating, Mammoth will only close an HTML element when necessary. Otherwise, elements are reused.

For instance, suppose one of the specified styles is p.Heading1 => h1. If Mammoth encounters a .docx paragraphs with the style Heading1, the .docx paragraph is converted to a h1 element with the same text. If the next .docx paragraph also has the style Heading1, then the text of that paragraph will be appended to the existing h1 element, rather than creating a new h1 element.

In most cases, you'll probably want to generate a new h1 element instead. You can specify this by using the :fresh modifier:

p.Heading1 => h1:fresh

The two consective Heading1 .docx paragraphs will then be converted to two separate h1 elements.

Reusing elements is useful in generating more complicated HTML structures. For instance, suppose your .docx contains asides. Each aside might have a heading and some body text, which should be contained within a single div.aside element. In this case, styles similar to AsideHeading => div.aside > h2:fresh and AsideText => div.aside > p:fresh might be helpful.

Document element matchers

Paragraphs and runs

Match any paragraph:

p

Match any run:

r

To match a paragraph or run with a specific style name, append a dot followed by the style name. For instance, to match a paragraph with the style Heading1:

p.Heading1

HTML paths

Single elements

The simplest HTML path is to specify single element. For instance, to specify an h1 element:

h1

To give an element a CSS class, append a dot followed by the name of the class:

h1.section-title

To require that an element is fresh, use :fresh:

h1:fresh

Modifiers must be used in the correct order:

h1.section-title:fresh

Nested elements

Use > to specify nested elements. For instance, to specify h2 within div.aside:

div.aside > h2

You can nest elements to any depth.