xmitter-11ty/eleventy.config.js

const { DateTime } = require("luxon");
const markdownItAnchor = require("markdown-it-anchor");

const pluginRss = require("@11ty/eleventy-plugin-rss");
const pluginSyntaxHighlight = require("@11ty/eleventy-plugin-syntaxhighlight");
const pluginNavigation = require("@11ty/eleventy-navigation");
const { EleventyHtmlBasePlugin } = require("@11ty/eleventy");

module.exports = function(eleventyConfig) {
  eleventyConfig.ignores.add("README.md");

  // Copy the contents of the `public` folder to the output folder
  // For example, `./public/css/` ends up in `_site/css/`
  eleventyConfig.addPassthroughCopy({
    "./public/": "/",
    "./node_modules/prismjs/themes/prism-okaidia.css": "/css/prism-okaidia.css"
  });

  // If your passthrough copy gets heavy and cumbersome, add this line
  // to emulate the file copy on the dev server. Learn more: https://www.11ty.dev/docs/copy/#emulate-passthrough-copy-during-serve
  // eleventyConfig.setServerPassthroughCopyBehavior("passthrough");

  // Add plugins
  eleventyConfig.addPlugin(pluginRss);
  eleventyConfig.addPlugin(pluginSyntaxHighlight);
  eleventyConfig.addPlugin(pluginNavigation);
  eleventyConfig.addPlugin(EleventyHtmlBasePlugin);

  eleventyConfig.addFilter("readableDate", (dateObj, format = "dd LLLL yyyy") => {
    return DateTime.fromJSDate(dateObj, {zone: 'utc'}).toFormat(format);
  });

  // https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-date-string
  eleventyConfig.addFilter('htmlDateString', (dateObj) => {
    return DateTime.fromJSDate(dateObj, {zone: 'utc'}).toFormat('yyyy-LL-dd');
  });

  // Get the first `n` elements of a collection.
  eleventyConfig.addFilter("head", (array, n) => {
    if(!Array.isArray(array) || array.length === 0) {
      return [];
    }
    if( n < 0 ) {
      return array.slice(n);
    }

    return array.slice(0, n);
  });

  // Return the smallest number argument
  eleventyConfig.addFilter("min", (...numbers) => {
    return Math.min.apply(null, numbers);
  });

  // Return all the tags used in a collection
  eleventyConfig.addFilter("getAllTags", collection => {
    let tagSet = new Set();
    for(let item of collection) {
      (item.data.tags || []).forEach(tag => tagSet.add(tag));
    }
    return Array.from(tagSet);
  });

  eleventyConfig.addFilter("filterTagList", function filterTagList(tags) {
    return (tags || []).filter(tag => ["all", "nav", "post", "posts"].indexOf(tag) === -1);
  });

  // Customize Markdown library settings:
  eleventyConfig.amendLibrary("md", mdLib => {
    mdLib.use(markdownItAnchor, {
      permalink: markdownItAnchor.permalink.ariaHidden({
        placement: "after",
        class: "direct-link",
        symbol: "#",
      }),
      level: [1,2,3,4],
      slugify: eleventyConfig.getFilter("slugify")
    });
  });

  return {
    // Control which files Eleventy will process
    // e.g.: *.md, *.njk, *.html, *.liquid
    templateFormats: [
      "md",
      "njk",
      "html",
      "liquid"
    ],

    // Pre-process *.md files with: (default: `liquid`)
    markdownTemplateEngine: "njk",

    // Pre-process *.html files with: (default: `liquid`)
    htmlTemplateEngine: "njk",

    // These are all optional (defaults are shown):
    dir: {
      input: ".",
      includes: "_includes",
      data: "_data",
      output: "_site"
    }

    // -----------------------------------------------------------------
    // Optional:

    // If your site deploys to a subdirectory, change `pathPrefix`.
    // Read more: https://www.11ty.dev/docs/config/#deploy-to-a-subdirectory-with-a-path-prefix

    // When paired with the HTML <base> plugin https://www.11ty.dev/docs/plugins/html-base/
    // it will transform any absolute URLs in your HTML to include this
    // folder name and does **not** affect where things go in the output folder.

    // Optional (default is shown)
    // pathPrefix: "/",
    // -----------------------------------------------------------------
  };
};