nxt-html-to-text
v7.1.3
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Advanced html to plain text converter
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html-to-text
Advanced converter that parses HTML and returns beautiful text.
Features
- Inline and block-level tags.
- Tables with colspans and rowspans.
- Links with both text and href.
- Word wrapping.
- Unicode support.
- Plenty of customization options.
Changelog
Available here: CHANGELOG.md
Version 6 contains a ton of changes, so it worth to take a look.
Version 7 contains an important change for custom formatters.
Installation
npm install html-to-text
Or when you want to use it as command line interface it is recommended to install it globally via
npm install html-to-text -g
Usage
const { htmlToText } = require('html-to-text');
const html = '<h1>Hello World</h1>';
const text = htmlToText(html, {
wordwrap: 130
});
console.log(text); // Hello World
Options
General options
Option | Default | Description
----------------------- | ------------ | -----------
baseElement
| 'body'
| The tag(s) whose text content will be captured from the html and added to the resulting text output.Single element or an array of elements can be specified, each as a single tag name with optional css class and id parameters e.g. ['p.class1.class2#id1#id2', 'p.class1.class2#id1#id2']
.
decodeOptions
| { isAttributeValue: false, strict: false }
| Text decoding options given to he.decode
. For more informations see the he module.
formatters
| {}
| An object with custom formatting functions for specific elements (see Override formatting section below).
limits
| | Describes how to limit the output text in case of large HTML documents.
limits.ellipsis
| '...'
| A string to insert in place of skipped content.
limits.maxChildNodes
| undefined
| Maximum number of child nodes of a single node to be added to the output. Unlimited if undefined.
limits.maxDepth
| undefined
| Stop looking for nodes to add to the output below this depth in the DOM tree. Unlimited if undefined.
limits.maxInputLength
| 16_777_216
| If the input string is longer than this value - it will be truncated and a message will be sent to stderr
. Ellipsis is not used in this case. Unlimited if undefined.
longWordSplit
| | Describes how to wrap long words.
longWordSplit.wrapCharacters
| []
| An array containing the characters that may be wrapped on. Checked in order, search stops once line length requirement can be met.
longWordSplit.forceWrapOnLimit
| false
| Break long words at the line length limit in case no better wrap opportunities found.
preserveNewlines
| false
| By default, any newlines \n
from the input HTML are collapsed into space as any other HTML whitespace characters. If true
, these newlines will be preserved in the output. This is only useful when input HTML carries some plain text formatting instead of proper tags.
returnDomByDefault
| true
| Convert the entire document if we don't find the tag defined in baseElement
.
tables
| []
| Allows to select certain tables by the class
or id
attribute from the HTML document. This is necessary because the majority of HTML E-Mails uses a table based layout. Prefix your table selectors with an .
for the class
and with a #
for the id
attribute. All other tables are ignored.You can assign true
to this attribute to select all tables.
tags
| | Describes how different tags should be formatted. See Tags section below.
whitespaceCharacters
| ' \t\r\n\f\u200b'
| A string of characters that are recognized as HTML whitespace. Default value uses the set of characters defined in HTML4 standard. (It includes Zero-width space compared to living standard.)
wordwrap
| 80
| After how many chars a line break should follow.Set to null
or false
to disable word-wrapping.
Options deprecated in version 6
Old option | Instead use
-------------------------- | -----------
hideLinkHrefIfSameAsText
| tags: { 'a': { options: { hideLinkHrefIfSameAsText: true } } }
ignoreHref
| tags: { 'a': { options: { ignoreHref: true } } }
ignoreImage
| tags: { 'img': { format: 'skip' } }
linkHrefBaseUrl
| tags: {
'a': { options: { baseUrl: 'https://example.com' } },
'img': { options: { baseUrl: 'https://example.com' } }
}
noAnchorUrl
| tags: { 'a': { options: { noAnchorUrl: true } } }
noLinkBrackets
| tags: { 'a': { options: { noLinkBrackets: true } } }
singleNewLineParagraphs
| tags: {
'p': { options: { leadingLineBreaks: 1, trailingLineBreaks: 1 } },
'pre': { options: { leadingLineBreaks: 1, trailingLineBreaks: 1 } }
}
unorderedListItemPrefix
| tags: { 'ul': { options: { itemPrefix: ' * ' } } }
uppercaseHeadings
| tags: {
'h1': { options: { uppercase: false } },
...
'table': { options: { uppercaseHeaderCells: false } }
}
Deprecated options will be removed with future major version update.
Options removed in version 6
Old option | Description
--------------- | -----------
format
| The way formatters are written has changed completely. New formatters have to be added to the formatters
option, old ones can not be reused without rewrite. See new instructions below.
Tags
Example for tag-specific options:
const { htmlToText } = require('html-to-text');
const html = '<a href="/page.html">Page</a>';
const text = htmlToText(html, {
tags: {
'a': { options: { baseUrl: 'https://example.com' } },
'figure': { format: 'block' }
}
});
console.log(text); // Page [https://example.com/page.html]
For new tags you have to specify the format
value. For tags listed below you can skip it and only provide options
. (Valid options listed in the next table.)
By default there are following tag to format assignments:
Tag name | Default format | Notes
------------- | ------------------- | -----
''
| inline
| Catch-all default for unknown tags.
a
| anchor
|
article
| block
|
aside
| block
|
blockquote
| blockquote
|
br
| lineBreak
|
div
| block
|
footer
| block
|
form
| block
|
h1
| heading
|
h2
| heading
|
h3
| heading
|
h4
| heading
|
h5
| heading
|
h6
| heading
|
header
| block
|
hr
| horizontalLine
|
img
| image
|
main
| block
|
nav
| block
|
ol
| orderedList
|
p
| paragraph
|
pre
| pre
|
table
| table
| there is also dataTable
format. Using it will be equivalent to setting tables
to true
. tables
option might be deprecated in the future.
ul
| unorderedList
|
wbr
| wbr
|
More formats also available for use:
skip
- as the name implies it skips the given tag with it's contents without printing anything.
Format options are specified for each tag indepentently:
Option | Default | Applies to | Description
------------------- | ----------- | ------------------ | -----------
leadingLineBreaks
| 1
, 2
or 3
| all block-level formatters | Number of line breaks to separate previous block from this one.Note that N+1 line breaks are needed to make N empty lines.
trailingLineBreaks
| 1
or 2
| all block-level formatters | Number of line breaks to separate this block from the next one.Note that N+1 line breaks are needed to make N empty lines.
baseUrl
| null
| anchor
, image
| Server host for link href
attributes and image src
attributes relative to the root (the ones that start with /
).For example, with baseUrl = 'http://asdf.com'
and <a href='/dir/subdir'>...</a>
the link in the text will be http://asdf.com/dir/subdir
.Keep in mind that baseUrl
should not end with a /
.
hideLinkHrefIfSameAsText
| false
| anchor
| By default links are translated in the following way:<a href='link'>text</a>
=> becomes => text [link]
.If this option is set to true
and link
and text
are the same, [link]
will be omitted and only text
will be present.
ignoreHref
| false
| anchor
| Ignore all links. Only process internal text of anchor tags.
noAnchorUrl
| true
| anchor
| Ignore anchor links (where href='#...'
).
noLinkBrackets
| false
| anchor
| Don't print brackets around links.
itemPrefix
| ' * '
| unorderedList
| String prefix for each list item.
uppercase
| true
| heading
| By default, headings (<h1>
, <h2>
, etc) are uppercased.Set this to false
to leave headings as they are.
length
| undefined
| horizontalLine
| Length of the line. If undefined then wordwrap
value is used. Falls back to 40 if that's also disabled.
trimEmptyLines
| true
| blockquote
| Trim empty lines from blockquote.While empty lines should be preserved in HTML, space-saving behavior is chosen as default for convenience.
uppercaseHeaderCells
| true
| table
, dataTable
| By default, heading cells (<th>
) are uppercased.Set this to false
to leave heading cells as they are.
maxColumnWidth
| 60
| table
, dataTable
| Data table cell content will be wrapped to fit this width instead of global wordwrap
limit.Set this to undefined
in order to fall back to wordwrap
limit.
colSpacing
| 3
| table
, dataTable
| Number of spaces between data table columns.
rowSpacing
| 0
| table
, dataTable
| Number of empty lines between data table rows.
Override formatting
This is significantly changed in version 6.
formatters
option is an object that holds formatting functions. They can be assigned to format different tags by key in the tags
option.
Each formatter is a function of four arguments that returns nothing. Arguments are:
elem
- the HTML element to be processed by this formatter;walk
- recursive function to process the children of this element. Called aswalk(elem.children, builder)
;builder
- BlockTextBuilder object. Manipulate this object state to build the output text;formatOptions
- options that are specified for a tag, along with this formatter (Note: if you need general html-to-text options - they are accessible viabuilder.options
).
Custom formatter example:
const { htmlToText } = require('html-to-text');
const html = '<foo>Hello World</foo>';
const text = htmlToText(html, {
formatters: {
// Create a formatter.
'fooBlockFormatter': function (elem, walk, builder, formatOptions) {
builder.openBlock({ leadingLineBreaks: formatOptions.leadingLineBreaks || 1 });
walk(elem.children, builder);
builder.addInline('!');
builder.closeBlock({ trailingLineBreaks: formatOptions.trailingLineBreaks || 1 });
}
},
tags: {
// Assign it to `foo` tags.
'foo': {
format: 'fooBlockFormatter',
options: { leadingLineBreaks: 1, trailingLineBreaks: 1 }
}
}
});
console.log(text); // Hello World!
Refer to built-in formatters for more examples.
Refer to BlockTextBuilder for available functions and arguments.
Note: BlockTextBuilder
got some important changes in the version 7. Positional arguments are deprecated and formatters written for the version 6 have to be updated accordingly in order to keep working after next major update.
Command Line Interface
It is possible to use html-to-text as command line interface. This allows an easy validation of your generated text and the integration in other systems that does not run on node.js.
html-to-text
uses stdin
and stdout
for data in and output. So you can use html-to-text
the following way:
cat example/test.html | html-to-text > test.txt
There also all options available as described above. You can use them like this:
cat example/test.html | html-to-text --tables=#invoice,.address --wordwrap=100 > test.txt
The tables
option has to be declared as comma separated list without whitespaces.
Example
Contributors
- @mlegenhausen - creator;
- @KillyMXI - maintainer since 2020;
- Everyone else who added something to the tool or helped us shaping it via issues and PRs.