hexo-util

Utilities for Hexo.

Table of contents

• Installation
• Usage
• Cache
• CacheStream
• camelCaseKeys
• createSha1Hash
• decodeURL
• deepMerge
• encodeURL
• escapeDiacritic
• escapeHTML
• escapeRegex
• full_url_for
• gravatar
• hash
• highlight
• htmlTag
• isExternalLink
• Pattern
• Permalink
• prettyUrls
• prismHighlight
• relative_url
• slugize
• spawn
• stripHTML
• wordWrap
• tocObj
• truncate
• unescapeHTML
• url_for
• bind(hexo)

Installation

$ npm install hexo-util --save

Usage

var util = require('hexo-util');

Cache()

A simple plain object cache

const cache = new Cache();

// set(key, value)
cache.set('foo', 'bar');

// get(key) => value
cache.get('foo');
// 'bar'

// has(key) => Boolean
cache.has('foo');
// true
cache.has('bar');
// false

// apply(key. value)
cache.apply('baz', () => 123);
// 123
cache.apply('baz', () => 456);
// 123
cache.apply('qux', 456);
// 456
cache.apply('qux', '789');
// 456

// size()
cache.size();
// 3

// dump()
cache.dump();
/*
{
  foo: 'bar',
  baz: 123,
  qux: 456
}
*/

// del(key)
cache.del('baz');
cache.has('baz');
// false

// flush()
cache.flush();
cache.has('foo');
// false
cache.size();
// 0

CacheStream()

Caches contents piped to the stream.

var stream = new CacheStream();

fs.createReadStream('/path/to/file').pipe(stream);

stream.on('finish', function(){
  // Read cache piped to the stream
  console.log(stream.getCache());

  // Destroy cache
  stream.destroy();
});

camelCaseKeys(obj, options)

Convert object keys to camelCase. Original keys will be converted to getter/setter and sync to the camelCase keys.

camelCaseKeys({
  foo_bar: 'test'
});
// { fooBar: 'test', foo_bar: 'test' }

createSha1Hash()

return SHA1 hash object. This is the same as calling createHash('utf8') in the node.js native module crypto.

const sha1 = createSha1Hash();
fs.createReadStream('/path/to/file')
 .pipe(sha1)
 .on('finish', () => {
   console.log(sha1.read());
 });

decodeURL(str)

Decode encoded URL or path. An alternative to the native decodeURI() function, with added ability to decode punycoded domain.

decodeURL('http://foo.com/b%C3%A1r')
// http://foo.com/bár

decodeURL('http://xn--br-mia.com/baz')
// http://bár.com/baz

decodeURL('/foo/b%C3%A1r/')
// /foo/bár/

/* Alternatively, Node 10+ offers native API to decode punycoded domain */
const {format} = require('url')
decodeURI(format(new URL('http://xn--br-mia.com.com/b%C3%A1r'), {unicode: true}))
// http://bár.com/báz

deepMerge(target, source)

Merges the enumerable properties of two objects deeply. target and source remain untouched.

// Merge deeply
const obj1 = {a: {b: 1, c: 1, d: {e: 1, f: 1}}};
const obj2 = {a: {b: 2, d: {f: 'f'} }};

deepMerge(obj1, obj2);
// {a: {b: 2, c: 1, d: {e: 1, f: 'f'} }}

// Arrays will be combined in the same property, similar to lodash.merge
const obj1 = { 'a': [{ 'b': 2 }, { 'd': 4 }] };
const obj2 = { 'a': [{ 'c': 3 }, { 'e': 5 }] };

deepMerge(obj1, obj2);
// { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] };

encodeURL(str)

Encode URL or path into a safe format.

encodeURL('http://foo.com/bár')
// http://foo.com/b%C3%A1r

encodeURL('/foo/bár/')
// /foo/b%C3%A1r/

escapeDiacritic(str)

Escapes diacritic characters in a string.

escapeHTML(str)

Escapes HTML entities in a string.

escapeHTML('<p>Hello "world".</p>')
// &lt;p&gt;Hello &quot;world&quot;.&lt;&#x2F;p&gt;

/* support escaped characters */
escapeHTML('&lt;foo>bar</foo&gt;')
// &lt;foo&gt;bar&lt;&#x2F;foo&gt;

escapeRegex(str)

Escapes special characters in a regular expression.

full_url_for(path)

Returns a url with the config.url prefixed. Output is encoded automatically. Requires bind(hexo).

_config.yml
url: https://example.com/blog # example

full_url_for('/a/path')
// https://example.com/blog/a/path

gravatar(str, [options])

Returns the gravatar image url from an email.

If you didn't specify the [options] parameter, the default options will apply. Otherwise, you can set it to a number which will then be passed on as the size parameter to Gravatar. Finally, if you set it to an object, it will be converted into a query string of parameters for Gravatar.

More info: Gravatar

gravatar('[email protected]')
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787
gravatar('[email protected]', 40)
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787?s=40
gravatar('[email protected]' {s: 40, d: 'https://via.placeholder.com/150'})
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787?s=40&d=https%3A%2F%2Fvia.placeholder.com%2F150

hash(str)

Generates SHA1 hash.

hash('123456');
// <Buffer 7c 4a 8d 09 ca 37 62 af 61 e5 95 20 94 3d c2 64 94 f8 94 1b>

highlight(str, [options])

Syntax highlighting for a code block.

htmlTag(tag, attrs, text, escape)

Creates a html tag.

htmlTag('img', {src: 'example.png'})
// <img src="example.png">

htmlTag('a', {href: 'http://hexo.io/'}, 'Hexo')
// <a href="http://hexo.io/">Hexo</a>

htmlTag('link', {href: 'http://foo.com/'}, '<a>bar</a>')
// <a href="http://foo.com/">&lt;bar&gt;</a>

htmlTag('a', {href: 'http://foo.com/'}, '<b>bold</b>', false)
// <a href="http://foo.com/"><b>bold</b></a>

/* text value of <style> won't be escaped, url is still encoded */
htmlTag('style', {}, 'p { content: "<"; background: url("bár.jpg"); }')
// <style>p { content: "<"; background: url("b%C3%A1r.jpg"); }</style>

/* support script tag with async/defer */
htmlTag('script', {src: '/foo.js', async: true}, '')
// <script src="/foo.js" async></script>

isExternalLink(url, sitehost, [exclude])

Returns if a given url is external link relative to given sitehost and [exclude].

// 'sitehost' can be a domain or url
isExternalLink('https://example.com', 'example.com');
// false
isExternalLink('https://example.com', 'https://example.com');
// false
isExternalLink('https://example.com', '//example.com/blog/');
// false

isExternalLink('/archives/foo.html', 'example.com');
// false
isExternalLink('https://foo.com/', 'example.com');
// true

isExternalLink('https://foo.com', 'example.com', ['foo.com', 'bar.com']);
// false
isExternalLink('https://bar.com', 'example.com', ['foo.com', 'bar.com']);
// false
isExternalLink('https://baz.com/', 'example.com', ['foo.com', 'bar.com']);
// true

Pattern(rule)

Parses the string and tests if the string matches the rule. rule can be a string, a regular expression or a function.

var pattern = new Pattern('posts/:id');

pattern.match('posts/89');
// {0: 'posts/89', 1: '89', id: '89'}

var pattern = new Pattern('posts/*path');

pattern.match('posts/2013/hello-world');
// {0: 'posts/2013/hello-world', 1: '2013/hello-world', path: '2013/hello-world'}

Permalink(rule, [options])

Parses a permalink.

var permalink = new Permalink(':year/:month/:day/:title', {
  segments: {
    year: /(\d{4})/,
    month: /(\d{2})/,
    day: /(\d{2})/
  }
});

permalink.parse('2014/01/31/test');
// {year: '2014', month: '01', day: '31', title: 'test'}

permalink.test('2014/01/31/test');
// true

permalink.stringify({year: '2014', month: '01', day: '31', title: 'test'})
// 2014/01/31/test

prettyUrls(url, [options])

Rewrite urls to pretty URLs.

Note: trailing_html ignores any link with a trailing index.html. (will not be rewritten to index).

prettyUrls('/foo/bar.html');
// /foo/bar.html
prettyUrls('/foo/bar/index.html');
// /foo/bar/index.html

prettyUrls('/foo/bar.html', { trailing_index: false });
// /foo/bar.html
prettyUrls('/foo/bar/index.html', { trailing_index: false });
// /foo/bar/

prettyUrls('/foo/bar.html', { trailing_html: false });
// /foo/bar
prettyUrls('/foo/bar/index.html', { trailing_html: false });
// /foo/bar/index.html

prettyUrls('/foo/bar.html', { trailing_index: false, trailing_html: false });
// /foo/bar
prettyUrls('/foo/bar/index.html', { trailing_index: false, trailing_html: false });
// /foo/bar/

prismHighlight(str, [options])

Syntax highlighting for a code block using PrismJS.

When isPreprocess is enabled, prismHighlight() will return PrismJS processed HTML snippet. Otherwise str will only be escaped and prismHighlight() will return the HTML snippet that is suitable for prism.js working in the Browser.

mark and firstLine options will have effect only when isPreprocess is disabled.

relative_url(from, to)

Returns the relative URL from from to to. Output is encoded automatically. Requires bind(hexo).

relative_url('foo/bar/', 'css/style.css')
// ../../css/style.css

slugize(str, [options])

Transforms a string into a clean URL-friendly string.

slugize('Hello World') = 'Hello-World'
slugize('Hellô Wòrld') = 'Hello-World'
slugize('Hello World', {separator: '_'}) = 'Hello_World'
slugize('Hello World', {transform: 1}) = 'hello-world'
slugize('Hello World', {transform: 2}) = 'HELLO-WORLD'

spawn(command, [args], [options])

Launches a new process with the given command. This method returns a promise.

More info: child_process.spawn()

spawn('cat', 'test.txt').then((content) => {
  console.log(content);
});

// $ cd "/target/folder"
// $ cat "foo.txt" "bar.txt"
spawn('cat', ['foo.txt', 'bar.txt'], { cwd: '/target/folder' }).then((content) => {
  console.log(content);
});

stripHTML(str)

Removes HTML tags in a string.

stripIndent(str)

Strip leading whitespace from each line in a string. The line with the least number of leading whitespace, ignoring empty lines, determines the number to remove. Useful for removing redundant indentation.

wordWrap(str, [options])

Wraps the string no longer than line width. This method breaks on the first whitespace character that does not exceed line width.

wordWrap('Once upon a time')
// Once upon a time

wordWrap('Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding a successor to the throne turned out to be more trouble than anyone could have imagined...')
// Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding\na successor to the throne turned out to be more trouble than anyone could have\nimagined...

wordWrap('Once upon a time', {width: 8})
// Once\nupon a\ntime

wordWrap('Once upon a time', {width: 1})
// Once\nupon\na\ntime

tocObj(str, [options])

Generate a table of contents in JSON format based on the given html string.

const html = [
  '<h1 id="title_1">Title 1</h1>',
  '<div id="title_1_1"><h2>Title 1.1</h2></div>',
  '<h3 id="title_1_1_1">Title 1.1.1</h3>',
  '<h2 id="title_1_2">Title 1.2</h2>',
  '<h2 id="title_1_3">Title 1.3</h2>',
  '<h3 id="title_1_3_1">Title 1.3.1</h3>',
  '<h1 id="title_2">Title 2</h1>',
  '<h2 id="title_2_1">Title 2.1</h2>'
].join('\n');

tocObj(html);
/*
[
  { text: 'Title 1', id: 'title_1', level: 1 },
  { text: 'Title 1.1', id: 'title_1_1', level: 2 },
  { text: 'Title 1.1.1', id: 'title_1_1_1', level: 3 },
  { text: 'Title 1.2', id: 'title_1_2', level: 2 },
  { text: 'Title 1.3', id: 'title_1_3', level: 2 },
  { text: 'Title 1.3.1', id: 'title_1_3_1', level: 3 },
  { text: 'Title 2', id: 'title_2', level: 1 },
  { text: 'Title 2.1', id: 'title_2_1', level: 2 },
]
*/

tocObj(html, { min_depth: 2 });
/*
[
  { text: 'Title 1.1', id: 'title_1_1', level: 2 },
  { text: 'Title 1.1.1', id: 'title_1_1_1', level: 3 },
  { text: 'Title 1.2', id: 'title_1_2', level: 2 },
  { text: 'Title 1.3', id: 'title_1_3', level: 2 },
  { text: 'Title 1.3.1', id: 'title_1_3_1', level: 3 },
  { text: 'Title 2.1', id: 'title_2_1', level: 2 },
]
*/

tocObj(html, { max_depth: 2 });
/*
[
  { text: 'Title 1', id: 'title_1', level: 1 },
  { text: 'Title 1.1', id: 'title_1_1', level: 2 },
  { text: 'Title 1.2', id: 'title_1_2', level: 2 },
  { text: 'Title 1.3', id: 'title_1_3', level: 2 },
  { text: 'Title 2', id: 'title_2', level: 1 },
  { text: 'Title 2.1', id: 'title_2_1', level: 2 },
]
*/

truncate(str, [options])

Truncates a given text after a given length if text is longer than length. The last characters will be replaced with the omission option for a total length not exceeding length.

truncate('Once upon a time in a world far far away')
// "Once upon a time in a world..."

truncate('Once upon a time in a world far far away', {length: 17})
// "Once upon a ti..."

truncate('Once upon a time in a world far far away', {length: 17, separator: ' '})
// "Once upon a..."

truncate('And they found that many people were sleeping better.', {length: 25, omission: '... (continued)'})
// "And they f... (continued)"

unescapeHTML(str)

Unescapes HTML entities in a string.

unescapeHTML('<p>Hello "world".</p>')
// <p>Hello "world".</p>

url_for(path, [option])

Returns a url with the root path prefixed. Output is encoded automatically. Requires bind(hexo).

_config.yml
root: /blog/ # example

url_for('/a/path')
// /blog/a/path

Relative link, follows relative_link option by default e.g. post/page path is '/foo/bar/index.html'

_config.yml
relative_link: true

url_for('/css/style.css')
// ../../css/style.css

/* Override option
 * you could also disable it to output a non-relative link,
 * even when `relative_link` is enabled and vice versa.
 */
url_for('/css/style.css', {relative: false})
// /css/style.css

bind(hexo)

Following utilities require bind(hexo) / bind(this) / call(hexo, input) / call(this, input) to parse the user config when initializing:

• full_url_for()
• url_for()
• relative_url()

Below examples demonstrate different approaches to creating a helper (each example is separated by /******/),

// Single function
const url_for = require('hexo-util').url_for.bind(hexo);

hexo.extend.helper.register('test_url', (str) => {
  return url_for(str);
})


/******/
// Multiple functions
const url_for = require('hexo-util').url_for.bind(hexo)

function testurlHelper(str) {
  return url_for(str);
}

hexo.extend.helper.register('test_url', testurlHelper);


/******/
// Functions separated into different files.
// test_url.js
module.exports = function(str) {
  const url_for = require('hexo-util').url_for.bind(this);
  return url_for(str);
}

// index.js
hexo.extend.helper.register('test_url', require('./test_url'));


/******/
// Function.call() approach also works
const {url_for} = require('hexo-util');
module.exports = function(str) {
  return url_for.call(this, str);
}

hexo.extend.helper.register('test_url', require('./test_url'));


/******/
// Separating functions into individual files
// Each file has multiple functions
// test_url.js
function testurlHelper(str) {
  const url_for = require('hexo-util').url_for.bind(this);
  return url_for(str);
}

module.exports =  {
  testurlHelper: testurlHelper
}

// index.js
hexo.extend.helper.register('test_url', require('./test_url').testurlHelper);

License

MIT