RSS Feed Generator

rss_generator.ts

import fs from "fs-extra";
import xml from "xml";
import { load } from "cheerio";
import xmlFormat from "xml-formatter";
import { marked } from "marked";

import { POSTLIST } from "./post-list.js";

const blogUrl: string = "https://arkandas.com/";
const feedName: string = "feed.rss";

(async function createRssFeed() {
  console.log("creating feed");
  const feedObject = {
    rss: [
      {
        _attr: {
          version: "2.0",
          "xmlns:content": "http://purl.org/rss/1.0/modules/content/",
          "xmlns:webfeeds": "http://webfeeds.org/rss/1.0",
          "xmlns:wfw": "http://wellformedweb.org/CommentAPI/",
          "xmlns:dc": "http://purl.org/dc/elements/1.1/",
          "xmlns:atom": "http://www.w3.org/2005/Atom",
          "xmlns:sy": "http://purl.org/rss/1.0/modules/syndication/",
          "xmlns:slash": "http://purl.org/rss/1.0/modules/slash/",
        },
      },
      {
        channel: [
          {
            title: "Arkandas",
          },
          {
            "atom:link": {
              _attr: {
                href: blogUrl + "rss/" + feedName,
                rel: "self",
                type: "application/rss+xml",
              },
            },
          },
          {
            link: blogUrl,
          },
          { description: "Electronics, Programming and Ideas" },
          { lastBuildDate: new Date().toUTCString() },
          { "webfeeds:icon": blogUrl + "logo.svg" },
          {
            "webfeeds:cover": {
              _attr: {
                image: blogUrl + "cover.png",
              },
            },
          },
          { "webfeeds:logo": blogUrl + "logo.svg" },
          { "webfeeds:accentColor": "#FFA45A" },
          { language: "en-US" },
          { generator: "arkandas rss-generator" },
          {
            image: [
              {
                url: blogUrl + "icons/" + "favicon-32.png",
              },
              {
                title: "Arkandas",
              },
              {
                link: blogUrl,
              },
              {
                width: "32",
              },
              {
                height: "32",
              },
            ],
          },
          {
            copyright: "All rights reserved 2024, Arkandas",
          },
          ...generateFeedItems(POSTLIST),
        ],
      },
    ],
  };

  const feed = '<?xml version="1.0" encoding="UTF-8"?>' + xml(feedObject);

  await fs.writeFile(
    "../public/rss/" + feedName,
    xmlFormat(feed, { collapseContent: true }),
    "utf8"
  );
})();

function generateFeedItems(
  posts: {
    id: any;
    permalink: any;
    author: any;
    title: any;
    summary: any;
    content: any;
    banner: any;
    miniature: any;
    card: any;
    date: any;
    isPrivate: any;
    categories: any[];
  }[]
) {
  const publicPosts = posts.filter(function (post) {
    return !post.isPrivate;
  });

  const sortedPosts = publicPosts.sort(function (first, second) {
    return new Date(second.date).getTime() - new Date(first.date).getTime();
  });

  const feedItems: any[] = [];

  feedItems.push(
    ...sortedPosts.map(function (post) {
      let postContent = fs
        .readFileSync("../public/" + post.content, "utf8")
        .toString()
        .replaceAll("posts/", blogUrl + "posts/");

      let categories: any[] = post.categories.map(function (category) {
        return { category: { _cdata: category } };
      });

      const feedItem = {
        item: [
          { title: post.title },
          { link: blogUrl + "blog/" + post.permalink + "/" },
          {
            "dc:creator": {
              _cdata: "Arkandas",
            },
          },
          {
            pubDate: new Date(post.date as string).toUTCString(),
          },
          ...categories,
          {
            guid: [
              { _attr: { isPermaLink: true } },
              blogUrl + "blog/" + post.permalink + "/",
            ],
          },
          {
            description: {
              _cdata: post.summary,
            },
          },
          {
            "content:encoded": {
              _cdata:
                '<img src="' +
                blogUrl +
                post.card +
                '" alt="' +
                post.permalink +
                " card" +
                '" class="webfeedsFeaturedVisual" width="1200" height="630">' +
                load(parsePostContent(postContent), { xmlMode: true }).html() +
                '<p><a href="https://arkandas.com/blog/' +
                post.permalink +
                '/">🌐 Read more</a></p>',
            },
          },
          {
            enclosure: [
              {
                _attr: {
                  length: getImageSizeInBytes("../public/" + post.card),
                },
              },
              { _attr: { type: "image/png" } },
              { _attr: { url: blogUrl + post.card } },
            ],
          },
        ],
      };
      return feedItem;
    })
  );
  return feedItems;
}

function parsePostContent(postContent: string) {
  return marked.parse(postContent.slice(0, 2500) + "...", {
    async: false,
  }) as string;
}

function getImageSizeInBytes(path: string) {
  let stats = fs.statSync(path);
  return stats.size;
}