Publican.lib

A standard library of functions and utilities for Publican static sites. Refer to publican.dev/tools/publican.lib/ for full documentation.

Import everything

Install Publican.lib in your Publican project:

npm install publican.lib

Then import it into your Publican configuration file:

// Publican configuration
import { libInit } from 'publican.lib';

Pass publican and tacs to the libInit() initialization function before calling await publican.build();

// ...set Publican defaults...

// initialize publican.lib
libInit(publican, tacs);

// optionally set the default language
tacs.lib.format.setLocale( 'en-US' );

// build
await publican.build();

Import individual utilities

Rather than using all functionality, you can choose to import specific functions. For example, to use all formatting and the nav.pagination():

// Publican configuration
import { Publican, tacs } from 'publican';

// import from Publican.lib
import * as format from 'publican.lib/format';
import { pagination } from 'publican.lib/nav';

// create a global functions object
tacs.fn = tacs.fn || {};

// use all tacs.fn.format functions in templates
tacs.fn.format = format;

// use tacs.fn.nav.pagination() function in templates
tacs.fn.nav = { pagination };

Utility functions

The util library provides utility functions you can use in your Publican configuration file or elsewhere.

env(name [, default])

Fetches an environment variable, converts to a numeric value where possible, and reverts to a default when necessary:

// isDev true when NODE_ENV is explicitly set to "development"
const isDev = (env('NODE_ENV', 'production') === 'development');

apiFetch(object)

Make an HTTP request, format the response, and cache when required. The object parameter properties:

• uri - required
• method such as "GET" (the default) or "POST"
• headers - optional object with name/value pairs
• authKey - optional request header Authorization token
• contentType - optional request header Content-Type (JSON by default)
• body - request body as a querystring, object, or array of arrays
• timeout - in millseconds (default of 10000 -- 10 seconds)
• cacheDir - cache directory location (not used by default)
• cacheMin - the number of minutes to cache data

The function returns an object with the following properties:

• ok: either true or false
• status: the HTTP status code (200 for OK)
• body: the resulting text or JSON response (or error message)
• error: error code
• cache: the cache file name when returning cached results

Example that caches a response for 10 minutes:

const res = await apiFetch({
  uri: 'https://api.site.com/call',
  authKey: 'mytoken',
  cacheDir: './_cache/'
});

if (res.ok) console.log(res.body);

normalize(str)

Normalizes a string to lowercase characters with hyphens in place of spaces:

normalize(' Publican Library 1 ');
// returns "publican-library-1"

strHash(str)

Hashes a string to an MD5 hex value.

strHash('Publican Library');

apiFetch() uses a hash of the HTTP URI, headers, and body as a filename when caching response data.

cspScript(code [, type])

When passed client-side JavaScript code in a string and an optional type attribute, cspScript() returns an object with the properties:

• code: the inline code inside a <script> tag, and
• hash: a SHA-256 hash for Content Security Policy script-src settings.

const tacs.myScript = cspScript('alert("Hello!")');

You can use this in a template:

<!-- Content Security Policy -->
<meta http-equiv="Content-Security-Policy" content="
default-src 'self';
script-src 'self' 'sha256-${ tacs.myScript.hash }';
">

<!-- add inline <script> -->
${ tacs.myScript.code }

Note: Publican minifies inline JavaScript by default. Always pass a minified script to cspScript() to ensure it's not minified and the CSP hash remains the same.

sortBy(prop)

A function to sort an array using property values, e.g.

const obj = [
  { name: "Craig" },
  { name: "Bob" },
  { name: "Anne" },
].sort( sortBy('name') );
// in order: Anne, Bob, Craig

fileInfo(path)

When passed a file path, it returns an object with the following properties:

• exists: true or false
• isFile: true when a file
• isDir: true when a directory
• modified: the last modification timestamp

Returns an object with file information:

const
  file = './somefile.txt',
  info = fileInfo(file);

if (info.exists) {

  console.log(file);

  if (info.isFile) {
    console.log('is a file');
  }
  else if (info.isDir) {
    console.log('is a directory');
  }

}

Event hook functions

The hook event functions append supplemental data and change some aspects of static site rendering.

processFileDate()

A processContent hook that sets the content date and modified properties for any content file using a file name pattern YYYY-MM-DD_something.md.

It does not alter the rendered file slug, but you can remove the date with:

// slug replacement strings - remove YYYY-MM-DD
publican.config.slugReplace.set(/\d{4}-\d{2}-\d{2}_/g, '');

contentFilename()

A processContent hook that parses a {{ filename }} above a code block in a markdown file. You can style the resulting HTML to show a tab or similar:

<p class="filename language-js">
  <dfn>myfile.js</dfn>
</p>
<pre class="language-js">...

htmlBlocks()

A processContent hook that replaces markdown lines starting ::: with HTML tags. For example:

::: div id="mydiv"

Some content

::: /div

results in the HTML:

<div id="mydiv">

  <p>Some content<p>

</div>

renderstartData()

A processRenderStart hook that modifies the title and description of all tag index files to create friendlier text such as:

• "JavaScript" posts
• List of 23 posts using the tag "JavaScript".

renderstartInlineScripts()

A processRenderStart hook that creates a global tacs.script JavaScript Map that defines inline scripts using cspScript():

1. tacs.script.get('theme'): an inline script that appends a data-theme attribute to the root <html> element using a localStorage value
2. tacs.script.get('speculation'): an inline speculation rules definition

prerenderInlineScripts()

A processPreRender hook that creates a data.script JavaScript Map for every page that defines an inline script using cspScript():

1. data.script.get('schema'): an inline schema.org structured data block.

renderstartTagScore()

A processRenderStart hook that creates a global tacs.tagScore JavaScript Map object that calculates a score for each tag (lesser-used tags have a higher score). This helps determine related articles.

prerenderRelated()

A processPreRender hook that appends a data.related array to every page with a list of related articles in order of relevancy. To output the three most-relevant related articles:

${ data?.related?.length ? `
  <aside>
    <h2>Related posts</h2>
    <nav>
      ${ data.related
          .slice(0,3)
          .map(p => `<p><a href="{ p.link }">${ p.title }</a></p>`)
          .join('') }
    </nav>
  </aside>
` : ''}

postrenderMeta()

A processPostRender hook that inserts a Publican <meta name="generator"> tag into the head of every HTML page.

Formatting functions

The format functions display locale-specific values such as dates and numbers.

setLocale(locale)

Defines the default locale when none is explicitly set in other formatting functions.

tacs.lib.format.setLocale( 'es-ES' );

number(num [, locale])

Returns a formatted number with appropriate thousand and fraction symbols.

<p>US: ${ tacs.lib.format.number( 12345.678 ) }</p>
<p>ES: ${ tacs.lib.format.number( 12345.678, 'es-ES' ) }</p>

US: 12,345.678

ES: 12.345,678

currency(num, currency [, locale])

Returns a formatted currency with appropriate thousand and fraction symbols.

<p>US: ${ tacs.lib.format.currency( 12345.678, 'USD' ) }</p>
<p>ES: ${ tacs.lib.format.currency( 12345.678, 'USD', 'es-ES' ) }</p>

US: $12,345.68

ES: 12.345,68 $

numberRound(num [, locale])

Rounds a number up depending on its size:

• < 1,000: to nearest 1
• > 1,000 and < 10,000: to nearest 10
• > 10,000 and < 100,000: to nearest 100
• etc.

<p>${ tacs.lib.format.numberRound( 12345 ) }</p>
<p>${ tacs.lib.format.numberRound( 123456 ) }</p>

12,400

124,000

dateHuman(date [, locale])

Returns a date in human-readable format:

<p>US: ${ tacs.lib.format.dateHuman('2026-09-05', 'en-US') }</p>
<p>UK: ${ tacs.lib.format.dateHuman('2026-09-05', 'en-GB') }</p>
<p>ES: ${ tacs.lib.format.dateHuman('2026-09-05', 'es-ES') }</p>

US: September 5, 2026

UK: 5 September 2026

ES: 5 de septiembre de 2026

dateUTC(date)

Returns a date in UTC format.

<pre>${ tacs.lib.format.dateUTC('2026-09-05T01:23:45') }</pre>

Sat, 05 Sep 2026 00:23:45 GMT

dateISO(date)

Returns a date in ISO format.

<pre>tacs.lib.format.dateISO('2026-09-05T01:23:45')</pre>

2026-09-05

dateISOfull(date)

Returns a full datetime in ISO format.

<pre>tacs.lib.format.dateISOfull('2026-09-05T01:23:45')</pre>

2026-09-05T00:23:45.000Z

dateYear(date)

Returns a year.

<pre>tacs.lib.format.dateYear('2026-09-05T01:23:45')</pre>

2025

Navigation functions

The nav functions provide HTML menus and pagination.

menuMain()

Creates a hierarchical main menu using the HTML <menu> structure with <details> and <summary> elements:

<menu>
  <li>
    <details>
      <summary><a href="/one/">Level One</a></summary>
      <menu>
        <li><strong>Active page</strong></li>
        <li>
          <details>
            <summary><a href="/two/">Level Two</a></summary>
            <menu>
              <li><a href="/sub2-1/">Sub-menu 2-1</a></li>
              <li><a href="/sub2-2/">Sub-menu 2-2</a></li>
            </menu>
          </details>
        </li>
      </menu>
    <details>
  </li>
</menu>

The function parameters in order:

• tacs: the global tacs object (required)
• currentPage: the current page's URL from data.link (required)
• allOpen: either -1=never open <details>, 0=when child is active, or 1=always
• maxLevel: the maximum depth of links
• omit: an array of root directory names to omit

Use in a template:

<nav id="main">
  ${ tacs.lib.nav.menuMain( tacs, data.link ) }
</nav>

menuDir()

Creates a hierarchical menu for a specific directory using a similar structure to menuMain, but all <details> have an open attribute set.

Parameters:

• tacs: the global tacs object (required)
• rootDir: the directory name (required)
• currentPage: the current page's URL from data.link (required)
• maxLevel: the maximum depth of links

Use in a template:

<nav id="documentation">
  ${ tacs.lib.nav.menuDir( tacs, 'doc', data.link ) }
</nav>

breadcrumb()

Creates a breadcrumb trail to the current page using the HTML structure:

<nav class="breadcrumb">
  <ol>
    <li><a href="/grandparent/">Grand parent</a></li>
    <li><a href="/parent/">Parent</a></li>
  </ol>
</nav>

Parameters:

• tacs: the global tacs object (required)
• currentPage: the current page's URL from data.link (required)

Use in a template:

${ tacs.lib.nav.breadcrumb( tacs, data.link ) }

tagList()

Generates a list of all tags ordered by ascending count of the articles using those tags. It results in the HTML structure:

<nav class="taglist">
  <ul>
    <li class="taglist5"><a href="/tag/one/">one <sup>19</sup></a></li>
    <li class="taglist4"><a href="/tag/two/">two <sup>17</sup></a></li>
    <li class="taglist3"><a href="/tag/three/">three <sup>15</sup></a></li>
    <li class="taglist2"><a href="/tag/four/">four <sup>13</sup></a></li>
    <li class="taglist2"><a href="/tag/five/">five <sup>13</sup></a></li>
    <li class="taglist1"><a href="/tag/six/">six <sup>10</sup></a></li>
  </ul>
</nav>

Parameters:

• tacs: the global tacs object (required)
• classPrefix: a class name to use (taglist by default)
• classMin: the minimum size class (1 by default)
• classMax: the maximum size class (5 by default)

The most-used tag has a class of taglist5. The least-used tag has a class of taglist1. All other tags have a value between.

Use in a template:

${ tacs.lib.nav.tagList(tacs) }

pagination()

Generates pagination for directory and tag index pages using the HTML structure:

<nav class="pagination">
  <ul>
    <li class="back"><span>◄</span></li>
    <li class="current"><strong>1</strong></li>
    <li><a href="/tag/one/1/">2</a></li>
    <li class="next"><a href="/tag/one/1/" title="next index page">►</a></li>
  </ul>
</nav>

Parameters:

• pagination: the page's data.pagination object (required)

${ tacs.lib.nav.pagination( data.pagination ) }

Feed functions

The feed functions help create machine-readable files in JSON and XML format.

rss(str, domain, root)

Removes invalid HTML attributes and ensures all URIs use absolute references.

<content:encoded><![CDATA[
${ tacs.lib.feed.rss( data.contentRendered, tacs.config.domain, tacs.root ) }
]]></content:encoded>

json(str, domain, root)

Does the same as rss() but also applies special encodings for JSON feeds that are replaced.

"content_html": "${ tacs.lib.feed.json( data.contentRendered, tacs.config.domain, tacs.root ) }"

escape(str)

Escapes single-line HTML and XML strings.

<title>${ tacs.lib.feed.escape( data.title ) }</title>

String replacements

The replace library provides a single replaceMap() function. It's passed the root path and returns a JavaScript Map with string replacement definitions.

Text replacements

• ＿＿/ (double underscore then slash) or −−ROOT−− is replaced with the root path
• −−COPYRIGHT−− is replaced with ©<CURRENT_YEAR>

Style replacements

All elements with a style attribute setting the text alignment have class="center" or class="right" assigned accordingly.

Table scrolling

All <table> elements get a <div class="tablescroll"> container to help with scrolling on smaller devices (set overflow-inline: auto; in CSS).

Unnecessary paragraphs

Unnecessary <p> tags are removed from around <img>, <svg>, and <iframe> elements.

Image handling

When not explicitly set on <img> tags:

• alt attributes are added, and
• loading="lazy" is set

JSON characters

Special characters for JSON feeds are replaced.