.eleventy.js

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

module.exports = function (eleventyConfig) {
    eleventyConfig.addPlugin(pluginRss);
    eleventyConfig.addPlugin(pluginSyntaxHighlight);
    eleventyConfig.setDataDeepMerge(true);

    eleventyConfig.addLayoutAlias("post", "layouts/post.njk");

    eleventyConfig.addFilter("readableDate", (dateObj) => {
        return DateTime.fromJSDate(dateObj, { zone: "utc" }).toFormat(
            "d LLL yyyy"
        );
    });

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

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

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

    eleventyConfig.addCollection("tagList", require("./_11ty/getTagList"));

    eleventyConfig.addPassthroughCopy("img");
    eleventyConfig.addPassthroughCopy("css");
    eleventyConfig.addPassthroughCopy("js");

    /* Markdown Plugins */
    let markdownIt = require("markdown-it");
    let markdownItAnchor = require("markdown-it-anchor");
    let options = {
        html: true,
        breaks: true,
        linkify: true,
    };
    let opts = {
        permalink: true,
        permalinkClass: "direct-link",
        permalinkSymbol: "#",
    };

    eleventyConfig.setLibrary(
        "md",
        markdownIt(options).use(markdownItAnchor, opts)
    );

    return {
        templateFormats: ["md", "njk", "html", "liquid"],

        // If your site lives in a different subdirectory, change this.
        // Leading or trailing slashes are all normalized away, so don’t worry about it.
        // If you don’t have a subdirectory, use "" or "/" (they do the same thing)
        // This is only used for URLs (it does not affect your file structure)
        pathPrefix: "/",

        markdownTemplateEngine: "liquid",
        htmlTemplateEngine: "njk",
        dataTemplateEngine: "njk",
        passthroughFileCopy: true,
        dir: {
            input: ".",
            includes: "_includes",
            data: "_data",
            output: "_site",
        },
    };
};