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

`` bash
$ npm install hexo-util --save
`

Usage

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

$3

A simple plain object cache

` js
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
`

$3

Caches contents piped to the stream.

` js
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();
});
`

$3

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

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

$3


return SHA1 hash object.
This is the same as calling createHash('utf8') in the node.js native module crypto.
` js
const sha1 = createSha1Hash();
fs.createReadStream('/path/to/file')
.pipe(sha1)
.on('finish', () => {
console.log(sha1.read());
});
`

$3

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

` js
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
`

$3

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

` js
// 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'} }}
`

` js
// 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 }] };
`

$3

Encode URL or path into a safe format.

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

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

$3

Escapes diacritic characters in a string.

$3

Escapes HTML entities in a string.

` js
escapeHTML('

Hello "world".

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

/ support escaped characters /
escapeHTML('<foo>bar// <foo>bar</foo>
`

$3

Escapes special characters in a regular expression.

$3

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

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

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

$3

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.

Option | Description | Default
--- | --- | ---
s | Output image size | 80
d | Default image |
f | Force default |
r | Rating |

More info: Gravatar

` js
gravatar('a@abc.com')
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787
gravatar('a@abc.com', 40)
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787?s=40
gravatar('a@abc.com' {s: 40, d: 'https://via.placeholder.com/150'})
// https://www.gravatar.com/avatar/b9b00e66c6b8a70f88c73cb6bdb06787?s=40&d=https%3A%2F%2Fvia.placeholder.com%2F150
`

$3

Generates SHA1 hash.

` js
hash('123456');
//
`

$3

Syntax highlighting for a code block.

Option | Description | Default
--- | --- | ---
gutter | Whether to show line numbers | true
wrap | Whether to wrap the code block in

| true
firstLine | First line number | 1
hljs | Whether to use the hljs-* prefix for CSS classes | false
lang | Language |
caption | Caption |
tab| Replace tabs |
autoDetect | Detect language automatically (warning: slow)
_Sublanguage highlight requires autoDetect to be enabled and lang to be unset_ | false
mark | Line highlight specific line(s) |
languageAttr | Output code language into data-language attr | false
stripIndent| Whether to strip leading whitespace via strip-indent | true

$3

Creates a html tag.

Option | Description | Default
--- | --- | ---
tag | Tag / element name |
attrs | Attribute(s) and its value.
Value is always escaped, URL is always encoded. |
text | Text, the value is always escaped
_(except for

/ support script tag with async/defer /
htmlTag('script', {src: '/foo.js', async: true}, '')
//
`

$3

Option | Description | Default
--- | --- | ---
url | The input URL. |
sitehost | The hostname / url of website. You can also pass hexo.config.url. |
exclude | Exclude hostnames. Specific subdomain is required when applicable, including www. | []

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

` js
// '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
`

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

` js
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
`




$3

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

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

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

` js
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'}
`

$3

Parses a permalink.

Option | Description
--- | ---
segments | Customize the rule of a segment in the permalink

` js
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
`

$3

Rewrite urls to pretty URLs.

Option | Description | Default
--- | --- | ---
trailing_index | /about/index.html -> /about/ when false | true
trailing_html | /about.html -> /about when false | true

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

` js
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/
`

$3

Syntax highlighting for a code block using PrismJS.

Option | Description | Default
--- | --- | ---
lineNumber | Whether to show line numbers | true
lang | Language | 'none'
tab| Replace tabs |
isPreprocess | Enable preprocess or not | true
mark | Highlight specific line |
firstLine | First line number |
caption | Caption |
stripIndent| Whether to strip leading whitespace via strip-indent | true


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.

$3

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

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

$3

Transforms a string into a clean URL-friendly string.

Option | Description | Default
--- | --- | ---
separator | Separator | -
transform | Transform the string into lower case (1) or upper case (2) |

` js
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'
`

$3

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

Option | Description | Default
--- | --- | ---
cwd | Current working directory of the child process |
env | Environment key-value pairs |
stdio | Child's stdio configuration | pipe
detached | The child will be a process group leader |
uid | Sets the user identity of the process |
gid | Sets the group identity of the process |
verbose | Display messages on the console | false
encoding | Sets the encoding of the output string | utf8

More info: child_process.spawn()

` js
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);
});
`

$3

Removes HTML tags in a string.

$3

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.

$3

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

Option | Description | Default
--- | --- | ---
width | Line width | 80

` js
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
`

$3

Generate a table of contents in JSON format based on the given html string. Headings with attribute data-toc-unnumbered="true" will be marked as unnumbered.

Option | Description | Default
--- | --- | ---
min_depth | The minimum level of TOC | 1
max_depth | The maximum level of TOC | 6


` js
const html = [
'

Title 1

',
'

Title 1.1

',
'

Title 1.1.1

',
'

Title 1.2

',
'

Title 1.3

',
'

Title 1.3.1

',
'

Title 2

',
'

Title 2.1

'
].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 },
]
*/

tocObj('

Reference

')
/*
[
{ text: 'Reference', id: 'reference', level: 1, unnumbered: true }
]
*/
`

$3

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.

Option | Description | Default
--- | --- | ---
length | Max length of the string | 30
omission | Omission text | ...
separator | truncate text at a natural break |

` js
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)"
`

$3

Unescapes HTML entities in a string.

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

Hello "world".


`

$3

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

Option | Description | Default
--- | --- | ---
relative | Output relative link | Value of config.relative_link

` yml
_config.yml
root: /blog/ # example
`

` js
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'

` yml
_config.yml
relative_link: true
`

` js
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 //),

` js
// 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

[Hexo]: http://hexo.io/