Skip to content
domstack
Documentation contents

Generate RSS and JSON feeds

All recipes

Use global.data.ts to inspect and render source pages, then let a feed template subscribe to the prepared records.

The following example generates an RSS and JSON Feed from the 10 most recent date-sorted pages using the blog layout and the AsyncIterator template type. It uses renderInnerPage() while global data is computed, so the template never receives the page graph. See the blog example’s global.data.ts and feeds.template.ts for a working implementation.

// src/global.data.ts
import type { AsyncGlobalDataFunction } from '@domstack/static/types.js'

export interface FeedItem {
  datePublished: string
  title: string
  urlPath: string
  contentHtml: string
}

export interface GlobalData {
  feedItems: FeedItem[]
}

export type FeedsTemplateData = Pick<GlobalData, 'feedItems'>

const globalData: AsyncGlobalDataFunction<GlobalData> = async ({ pages }) => {
  const posts: typeof pages = []
  for (const page of pages) {
    if (page.pageInfo.path.startsWith('blog/') && page.vars.layout === 'blog') {
      posts.push(page)
    }
  }

  posts.sort((a, b) => new Date(b.vars.publishDate).valueOf() - new Date(a.vars.publishDate).valueOf())

  const feedItems: FeedItem[] = []
  for (const page of posts.slice(0, 10)) {
    feedItems.push({
      datePublished: String(page.vars.publishDate),
      title: String(page.vars.title),
      urlPath: page.pageInfo.url,
      contentHtml: String(await page.renderInnerPage()),
    })
  }

  return { feedItems }
}

export default globalData

// src/feeds.template.ts
import jsonfeedToAtom from 'jsonfeed-to-atom'
import type { DataDeps, TemplateAsyncIterator } from '@domstack/static/types.js'
import type { FeedsTemplateData } from './global.data.js'

interface TemplateVars {
  title: string;
  layout: string;
  siteName: string;
  homePageUrl: string;
  authorName: string;
  authorUrl: string;
  authorImgUrl?: string;
  siteDescription: string;
  language: string;
}

export const dataDeps = ['feedItems'] satisfies DataDeps<FeedsTemplateData>

const feedsTemplate: TemplateAsyncIterator<TemplateVars, FeedsTemplateData> = async function * ({
  vars: {
    siteName,
    siteDescription,
    homePageUrl,
    authorName,
    authorUrl,
    authorImgUrl,
  },
  data,
}) {
  const items = []
  for (const item of data.feedItems) {
    items.push({
      date_published: item.datePublished,
      title: item.title,
      url: `${homePageUrl}${item.urlPath}`,
      id: `${homePageUrl}${item.urlPath}#${item.datePublished}`,
      content_html: item.contentHtml,
    })
  }

  const jsonFeed = {
    version: 'https://jsonfeed.org/version/1',
    title: siteName,
    home_page_url: homePageUrl,
    feed_url: `${homePageUrl}/feed.json`,
    description: siteDescription,
    author: {
      name: authorName,
      url: authorUrl,
      avatar: authorImgUrl
    },
    items,
  }

  yield {
    content: JSON.stringify(jsonFeed, null, '  '),
    outputName: './feeds/feed.json'
  }

  yield {
    content: jsonfeedToAtom(jsonFeed),
    outputName: './feeds/feed.xml'
  }
}

export default feedsTemplate
Documentation