RSS Feed Generation

/**
 * Generate RSS feed as HTTP Response
 * @param options - RSS feed configuration
 * @returns Promise<Response> with XML content and application/xml header
 */
function rss(options: RSSOptions): Promise<Response>;

// In src/pages/rss.xml.js
import rss from "@astrojs/rss";

export async function GET(context) {
  return rss({
    title: "My Blog",
    description: "Personal thoughts and tutorials",
    site: context.site,
    items: [
      {
        title: "Getting Started with Astro",
        link: "/blog/getting-started",
        pubDate: new Date("2023-06-01"),
        description: "Learn the basics of Astro development",
        categories: ["tutorial", "astro"],
        author: "john@example.com"
      }
    ],
    customData: '<language>en-us</language>',
    stylesheet: "/rss-styles.xsl"
  });
}

/**
 * Generate RSS feed as XML string
 * @param options - RSS feed configuration
 * @returns Promise<string> containing RSS XML
 */
function getRssString(options: RSSOptions): Promise<string>;

import { getRssString } from "@astrojs/rss";

export async function GET(context) {
  const rssString = await getRssString({
    title: "My Blog",
    description: "Personal blog posts",
    site: context.site,
    items: blogPosts,
  });

  return new Response(rssString, {
    headers: {
      "Content-Type": "application/xml",
      "Cache-Control": "public, max-age=3600"
    },
  });
}

interface RSSOptions {
  /** Title of the RSS Feed (required) */
  title: string;
  /** Description of the RSS Feed (required) */
  description: string;
  /** 
   * Base URL to use for RSS feed links (required)
   * Recommend using context.site from Astro endpoint
   */
  site: string | URL;
  /** List of RSS feed items to render (required) */
  items: RSSFeedItem[] | GlobResult;
  /** Specify arbitrary XML namespaces on opening <rss> tag */
  xmlns?: Record<string, string>;
  /**
   * Specifies a local custom XSL stylesheet path
   * Ex. '/public/custom-feed.xsl' or boolean false to disable
   */
  stylesheet?: string | boolean;
  /** Specify custom XML data in opening of channel */
  customData?: string;
  /** Add trailing slashes to URLs (default: true) */
  trailingSlash?: boolean;
}

// For podcast feeds with iTunes namespace
export const GET = () => rss({
  title: "My Podcast",
  description: "Weekly tech discussions",
  site: "https://example.com",
  items: episodes,
  xmlns: {
    itunes: "http://www.itunes.com/dtds/podcast-1.0.dtd",
    googleplay: "http://www.google.com/schemas/play-podcasts/1.0"
  },
  customData: `
    <itunes:author>John Doe</itunes:author>
    <itunes:category text="Technology"/>
    <googleplay:author>John Doe</googleplay:author>
  `,
});

export const GET = () => rss({
  title: "Video Blog",
  description: "Weekly video content",
  site: "https://example.com",
  items: [
    {
      title: "Episode 1: Introduction",
      link: "/episodes/intro",
      pubDate: new Date("2023-06-01"),
      description: "Welcome to our new series",
      content: `
        <h1>Episode 1: Introduction</h1>
        <p>Full episode transcript and show notes...</p>
        <img src="/images/episode1.jpg" alt="Episode thumbnail" />
      `,
      enclosure: {
        url: "/media/episode1.mp4",
        length: 52428800, // file size in bytes
        type: "video/mp4"
      },
      categories: ["video", "tutorial"]
    }
  ]
});

export const GET = () => rss({
  title: "Styled Feed",
  description: "RSS feed with custom styling",
  site: "https://example.com",
  items: posts,
  stylesheet: "/pretty-feed.xsl", // XSL stylesheet for browser display
});

interface RSSFeedItem {
  /** Link to item (optional if description provided) */
  link?: string;
  /** Full HTML content of the item */
  content?: string;
  /** Title of item (optional if description provided) */
  title?: string;
  /** Publication date - accepts Date, string, or number */
  pubDate?: Date | string | number;
  /** Item description (optional if title provided) */
  description?: string;
  /** Custom XML data to inject into this item */
  customData?: string;
  /** Categories or tags related to the item */
  categories?: string[];
  /** The item author's email address */
  author?: string;
  /** URL of a page for comments related to the item */
  commentsUrl?: string;
  /** RSS channel that the item came from for republished content */
  source?: RSSFeedItemSource;
  /** Media object that belongs to the item (podcasts, videos) */
  enclosure?: RSSFeedItemEnclosure;
}

interface RSSFeedItemSource {
  /** Title of the original RSS channel */
  title: string;
  /** URL of the original RSS feed */
  url: string;
}

interface RSSFeedItemEnclosure {
  /** URL where the media can be found */
  url: string;
  /** Size of the file in bytes */
  length: number;
  /** MIME type of the media file */
  type: string;
}

// Missing required fields
// Error: "[RSS] Invalid or missing options:
//         At least title or description must be provided. (items)
//         The `items` property requires at least the `title` or `description` key..."

// Invalid types
// Error: "[RSS] Invalid or missing options:
//         "title" should be string, not undefined. (title)"

// Invalid URL format
// Error: "[RSS] Invalid or missing options:
//         "site" should be string, not number. (site)"