Filters

Maizzle includes filters that enable you to do anything you want to text nodes inside elements that you mark with custom attributes.

Usage

Add a filters object to your Maizzle config:

config.js
      export default {
  filters: {},
}

    

Each entry in this object is made up of a key: value pair.

  • key represents a custom HTML attribute name
  • value is a function that accepts two arguments, and must return a string

Example:

config.js
      export default {
  filters: {
    uppercase: str => str.toUpperCase(),
  }
}

    

Used in a Template:

emails/example.html
      <p uppercase>Here is some foo.</p>

    

Result:

      <p>HERE IS SOME FOO BAR.</p>

    

Of course, this is just a dumb example - you could imagine more complex scenarios where you pull in packages and do stuff like:

  • compile CSS in some <style> tag with Sass or others
  • normalize html whitespace in parts of your code
  • create various content filters
  • ...

Disabling

You may disable all filters by setting the option to false:

config.js
      export default {
  filters: false,
}

    

Default filters

The following filters are included by default.

append

Append text to the end of the string.

example.html
      <p append=" bar">foo</p>
<!-- <p>foo bar</p> -->

    

prepend

Prepend text to the beginning of the string.

example.html
      <p prepend="foo ">bar</p>
<!-- <p>foo bar</p> -->

    

uppercase

Uppercase the string.

example.html
      <p uppercase>foo</p>
<!-- <p>FOO</p> -->

    

lowercase

Lowercase the string.

example.html
      <p lowercase>FOO</p>
<!-- <p>foo</p> -->

    

capitalize

Uppercase the first letter of the string.

example.html
      <p capitalize>foo</p>
<!-- <p>Foo</p> -->

    

ceil

Round up to the nearest integer.

example.html
      <p ceil>1.2</p>
<!-- <p>2</p> -->

    

floor

Round down to the nearest integer.

example.html
      <p ceil>1.2</p>
<!-- <p>1</p> -->

    

round

Round to the nearest integer.

example.html
      <p round>1234.567</p>
<!-- <p>1235</p> -->

    

escape

Escapes a string by replacing characters with escape sequences (so that the string can be used in a URL, for example).

example.html
      <p escape>"&'<></p>
<!-- <p>&#34;&amp;&#39;&lt;&gt;</p> -->

    

escape-once

Escapes a string without changing existing escaped entities.

example.html
      <p escape-once>1 &lt; 2 &amp; 3</p>
<!-- <p>1 &lt; 2 &amp; 3</p> -->

    

lstrip

Remove leading whitespace from the string.

example.html
      <p lstrip> test </p>
<!-- <p>test </p> -->

    

rstrip

Remove trailing whitespace from the string.

example.html
      <p rstrip> test </p>
<!-- <p> test</p> -->

    

trim

Remove leading and trailing whitespace from the string.

example.html
      <p trim> test </p>
<!-- <p>test</p> -->

    

minus

Subtracts one number from another.

example.html
      <p minus="2">3</p>
<!-- <p>1</p> -->

    

plus

Adds one number to another.

example.html
      <p plus="2">3</p>
<!-- <p>5</p> -->

    

multiply

Alias: times

example.html
      <p multiply="2">1.2</p>
<!-- <p>2.4</p> -->

    

divide-by

Alias: divide

example.html
      <div divide-by="2">1.2</div>
<!-- <p>0.6</p> -->

    

modulo

Returns the remainder of one number divided by another.

example.html
      <p modulo="2">3</p>
<!-- <p>1</p> -->

    

newline-to-br

Insert an HTML line break (<br />) in front of each newline (\n) in a string.

example.html
      <p newline-to-br>
  test
  test
</p>
<!-- <p><br>  test<br>  test<br></p> -->

    

strip-newlines

Remove any newline characters (line breaks) from the string.

example.html
      <p strip_newlines>
  test
  test
</p>
<!-- <p>  test  test</p> -->

    

remove

Remove every occurrence of text from the string.

example.html
      <p remove="rain">I strained to see the train through the rain</p>
<!-- <p>I sted to see the t through the </p> -->

    

remove-first

Remove the first occurrence of text from the string.

example.html
      <p remove-first="rain">I strained to see the train through the rain</p>
<!-- <p>I sted to see the train through the rain</p> -->

    

replace

Replace every occurrence of the first argument with the second argument.

You must separate arguments with a pipe character (|).

example.html
      <p replace="1|test">test</p>
<!-- <p>1es1</p> -->

    

replace-first

Replace the first occurrence of the first argument with the second argument.

You must separate arguments with a pipe character (|).

example.html
      <p replace-first="t|b">test</p>
<!-- <p>best</p> -->

    

size

Return the number of characters in the string.

example.html
      <p size>one</p>
<!-- <p>3</p> -->

    

slice

Return a slice of the string starting at the provided index.

example.html
      <p slice="1">test</p>
<!-- <p>est</p> -->

    

You may pass a startIndex and endIndex:

example.html
      <p slice="0,-1">test</p>
<!-- <p>tes</p> -->

    

truncate

Shorten a string down to the number of characters passed as the argument.

example.html
      <p truncate="17">Ground control to Major Tom.</p>
<!-- <p>Ground control to...</p> -->

    

You may pass a custom ellipsis as the second argument.

Separate arguments with a comma:

example.html
      <p truncate="17, no one">Ground control to Major Tom.</p>
<!-- <p>Ground control to no one</p> -->

    

truncate-words

Shorten a string down to the number of words passed as the argument.

example.html
      <p truncate-words="2">Ground control to Major Tom.</p>
<!-- <p>Ground control...</p> -->

    

You may pass a custom ellipsis as the second argument.

Separate arguments with a comma:

example.html
      <p truncate-words="2, over and out">Ground control to Major Tom.</p>
<!-- <p>Ground control over and out</p> -->

    

url-decode

Decode a string that has been encoded as a URL.

example.html
      <p url-decode>%27Stop%21%27+said+Fred</p>
<!-- <p>'Stop!' said Fred</p> -->

    

url-encode

Convert any URL-unsafe characters in a string into percent-encoded characters.

example.html
      <p url-encode>[email protected]</p>
<!-- <p>user%40example.com</p> -->

    
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