Display webmentions

.eleventy.js

@@ -7,6 +7,15 @@ const markdownItAttrs = require("markdown-it-attrs");
 const markdownItEleventyImg = require("markdown-it-eleventy-img");
 const pluginRss = require("@11ty/eleventy-plugin-rss");
 const embedYouTube = require("eleventy-plugin-youtube-embed");
+const sanitizeHtml = require("sanitize-html");
+const metadata = require("./src/_data/metadata.json");
+
+const sanitize = (html) => {
+  return sanitizeHtml(html, {
+    allowedTags: ['b', 'i', 'em', 'strong', 'a'],
+    allowedAttributes: { 'a': ['href'] }
+  });
+};
 
 module.exports = function(eleventyConfig) {
   eleventyConfig.addPlugin(embedYouTube);
@@ -57,7 +66,49 @@ module.exports = function(eleventyConfig) {
       return '<iframe width="560" height="315" src="https://www.youtube.com/embed/' + videoId + '" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>';
     });
   });
+  eleventyConfig.addFilter('webmentionsByUrl', function(webmentions, url) {
+    const allowedTypes = ['in-reply-to', 'like-of', 'repost-of'];
+    const hasRequiredFields = mention => {
+        const { author, published, content } = mention;
+        return author.name && published && content;
+    };
+    const matchesUrl = mention => {
+      return mention['wm-target'] === url;
+    };
 
+    const filteredMentions = webmentions
+      .filter(mention => {
+        const isAllowedType = allowedTypes.includes(mention['wm-property']);
+        if (isAllowedType) {
+          const isReply = mention['wm-property'] === 'in-reply-to';
+          if (isReply) {
+            return matchesUrl(mention) && hasRequiredFields(mention);
+          }
+          return matchesUrl(mention);
+        }
+      }
+    );
+    const sanitizedMentions = filteredMentions.map((mention) => {
+      if (mention?.content?.html) {
+        mention.content.html = sanitize(mention.content.html);
+        const mastodonInstance = metadata.author.mastodon.instance;
+        const mastodonUsername = metadata.author.mastodon.username;
+        const mentionLink = `<a href="https://${mastodonInstance}/@${mastodonUsername}">@${metadata.author.mastodon.username}</a> `;
+        if (mention.content.html.startsWith(mentionLink)) {
+          mention.content.html = mention.content.html.substring(mentionLink.length)
+        }
+      }
+      return mention;
+    });
+    const sortedMentions = sanitizedMentions.reduce((accumulator, mention) => {
+      const key = mention['wm-property'];
+      const curGroup = accumulator[key] ?? [];
+      return { ...accumulator, [key]: [...curGroup, mention] };
+    }, {});
+
+    console.log(sortedMentions);
+    return sortedMentions;
+  });
 
   const markdownLibrary = markdownIt({ html: true })
     .use(markdownItAnchor, { slugify })