astro/packages/astro-rss/README.md

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# @astrojs/rss 📖
This package brings fast RSS feed generation to blogs and other content sites built with [Astro](https://astro.build/). For more information about RSS feeds in general, see [aboutfeeds.com](https://aboutfeeds.com/).
## Installation
Install the `@astrojs/rss` package into any Astro project using your preferred package manager:
```bash
# npm
npm i @astrojs/rss
# yarn
yarn add @astrojs/rss
# pnpm
pnpm i @astrojs/rss
```
## Example usage
The `@astrojs/rss` package provides helpers for generating RSS feeds within [Astro endpoints][astro-endpoints]. This unlocks both static builds _and_ on-demand generation when using an [SSR adapter](https://docs.astro.build/en/guides/server-side-rendering/#enabling-ssr-in-your-project).
For instance, say you need to generate an RSS feed for all posts under `src/content/blog/` using content collections.
Start by [adding a `site` to your project's `astro.config` for link generation](https://docs.astro.build/en/reference/configuration-reference/#site). Then, create an `rss.xml.js` file under your project's `src/pages/` directory, and [use `getCollection()`](https://docs.astro.build/en/guides/content-collections/#getcollection) to generate a feed from all documents in the `blog` collection:
```js
// src/pages/rss.xml.js
import rss from '@astrojs/rss';
import { getCollection } from 'astro:content';
export async function get(context) {
const posts = await getCollection('blog');
return rss({
title: 'Buzzs Blog',
description: 'A humble Astronauts guide to the stars',
// Pull in your project "site" from the endpoint context
// https://docs.astro.build/en/reference/api-reference/#contextsite
site: context.site,
items: posts.map((post) => ({
// Assumes all RSS feed item properties are in post frontmatter
...post.data,
// Generate a `url` from each post `slug`
// This assumes all blog posts are rendered as `/blog/[slug]` routes
// https://docs.astro.build/en/guides/content-collections/#generating-pages-from-content-collections
link: `/blog/${post.slug}/`,
})),
});
}
```
Read **[Astro's RSS docs][astro-rss]** for more on using content collections, and instructions for globbing entries in `/src/pages/`.
## `rss()` configuration options
The `rss` default export offers a number of configuration options. Here's a quick reference:
```js
export function get(context) {
return rss({
// `<title>` field in output xml
title: 'Buzzs Blog',
// `<description>` field in output xml
description: 'A humble Astronauts guide to the stars',
// provide a base URL for RSS <item> links
site: context.site,
// list of `<item>`s in output xml
items: [...],
// (optional) absolute path to XSL stylesheet in your project
stylesheet: '/rss-styles.xsl',
// (optional) inject custom xml
customData: '<language>en-us</language>',
// (optional) add arbitrary metadata to opening <rss> tag
xmlns: { h: 'http://www.w3.org/TR/html4/' },
// (optional) add trailing slashes to URLs (default: true)
trailingSlash: false
});
}
```
### title
Type: `string (required)`
The `<title>` attribute of your RSS feed's output xml.
### description
Type: `string (required)`
The `<description>` attribute of your RSS feed's output xml.
### site
Type: `string (required)`
The base URL to use when generating RSS item links. We recommend using the [endpoint context object](https://docs.astro.build/en/reference/api-reference/#contextsite), which includes the `site` configured in your project's `astro.config.*`:
```ts
import rss from '@astrojs/rss';
export const get = (context) => rss({
site: context.site,
...
});
```
### items
Type: `RSSFeedItem[] (required)`
A list of formatted RSS feed items. See [Astro's RSS items documentation](https://docs.astro.build/en/guides/rss/#generating-items) for usage examples to choose the best option for you.
When providing a formatted RSS item list, see the [`RSSFeedItem` type reference](#rssfeeditem).
### drafts
Type: `boolean (optional)`
**Deprecated**: Manually filter `items` instead.
Set `drafts: true` to include [draft posts](https://docs.astro.build/en/guides/markdown-content/#draft-pages) in the feed output. By default, this option is `false` and draft posts are not included.
### stylesheet
Type: `string (optional)`
An absolute path to an XSL stylesheet in your project. If you dont have an RSS stylesheet in mind, we recommend the [Pretty Feed v3 default stylesheet](https://github.com/genmon/aboutfeeds/blob/main/tools/pretty-feed-v3.xsl), which you can download from GitHub and save into your project's `public/` directory.
### customData
Type: `string (optional)`
A string of valid XML to be injected between your feed's `<description>` and `<item>` tags. This is commonly used to set a language for your feed:
```js
import rss from '@astrojs/rss';
export const get = () => rss({
...
customData: '<language>en-us</language>',
});
```
### xmlns
Type: `Record<string, string> (optional)`
An object mapping a set of `xmlns` suffixes to strings of metadata on the opening `<rss>` tag.
For example, this object:
```js
rss({
...
xmlns: { h: 'http://www.w3.org/TR/html4/' },
})
```
Will inject the following XML:
```xml
<rss xmlns:h="http://www.w3.org/TR/html4/"...
```
### content
The `content` key contains the full content of the post as HTML. This allows you to make your entire post content available to RSS feed readers.
**Note:** Whenever you're using HTML content in XML, we suggest using a package like [`sanitize-html`](https://www.npmjs.com/package/sanitize-html) in order to make sure that your content is properly sanitized, escaped, and encoded.
[See our RSS documentation](https://docs.astro.build/en/guides/rss/#including-full-post-content) for examples using content collections and glob imports.
### `trailingSlash`
Type: `boolean (optional)`
Default: `true`
By default, the library will add trailing slashes to the emitted URLs. To prevent this behavior, add `trailingSlash: false` to the `rss` function.
```js
import rss from '@astrojs/rss';
export const get = () =>
rss({
trailingSlash: false,
});
```
## `RSSFeedItem`
An `RSSFeedItem` is a single item in the list of items in your feed. It represents a story, with `link`, `title`, and `pubDate` fields. There are further optional fields defined below. You can also check the definitions for the fields in the [RSS spec](https://validator.w3.org/feed/docs/rss2.html#ltpubdategtSubelementOfLtitemgt).
An example feed item might look like:
```js
const item = {
title: 'Alpha Centauri: so close you can touch it',
link: '/blog/alpha-centuari',
pubDate: new Date('2023-06-04'),
description:
'Alpha Centauri is a triple star system, containing Proxima Centauri, the closest star to our sun at only 4.24 light-years away.',
categories: ['stars', 'space'],
};
```
### `title`
Type: `string (required)`
The title of the item in the feed.
### `link`
Type: `string (required)`
The URL of the item on the web.
### `pubDate`
Type: `Date (required)`
Indicates when the item was published.
### `description`
Type: `string (optional)`
A synopsis of your item when you are publishing the full content of the item in the `content` field. The `description` may alternatively be the full content of the item in the feed if you are not using the `content` field (entity-coded HTML is permitted).
### `content`
Type: `string (optional)`
The full text content of the item suitable for presentation as HTML. If used, you should also provide a short article summary in the `description` field.
See the [recommendations from the RSS spec for how to use and differentiate between `description` and `content`](https://www.rssboard.org/rss-profile#namespace-elements-content-encoded).
### `categories`
Type: `string[] (optional)`
A list of any tags or categories to categorize your content. They will be output as multiple `<category>` elements.
### `author`
Type: `string (optional)`
The email address of the item author. This is useful for indicating the author of a post on multi-author blogs.
### `commentsUrl`
Type: `string (optional)`
The URL of a web page that contains comments on the item.
### `source`
Type: `object (optional)`
An object that defines the `title` and `url` of the original feed for items that have been republished from another source. Both are required properties of `source` for proper attribution.
```js
const item = {
title: 'Alpha Centauri: so close you can touch it',
link: '/blog/alpha-centuari',
pubDate: new Date('2023-06-04'),
description:
'Alpha Centauri is a triple star system, containing Proxima Centauri, the closest star to our sun at only 4.24 light-years away.',
source: {
title: 'The Galactic Times',
url: 'https://galactictimes.space/feed.xml',
},
};
```
#### `source.title`
Type: `string (required)`
The name of the original feed in which the item was published. (Note that this is the feed's title, not the individual article title.)
#### `source.url`
Type: `string (required)`
The URL of the original feed in which the item was published.
### `enclosure`
Type: `object (optional)`
An object to specify properties for an included media source (e.g. a podcast) with three required values: `url`, `length`, and `type`.
```js
const item = {
title: 'Alpha Centauri: so close you can touch it',
link: '/blog/alpha-centuari',
pubDate: new Date('2023-06-04'),
description:
'Alpha Centauri is a triple star system, containing Proxima Centauri, the closest star to our sun at only 4.24 light-years away.',
enclosure: {
url: '/media/alpha-centauri.aac',
length: 124568,
type: 'audio/aac',
},
};
```
#### `enclosure.url`
Type: `string (required)`
The URL where the media can be found. If the media is hosted outside of your own domain you must provide a full URL.
#### `enclosure.length`
Type: `number (required)`
The size of the file found at the `url` in bytes.
#### `enclosure.type`
Type: `string (required)`
The [MIME type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types) for the media item found at the `url`.
## `rssSchema`
When using content collections, you can configure your collection schema to enforce expected [`RSSFeedItem`](#items) properties. Import and apply `rssSchema` to ensure that each collection entry produces a valid RSS feed item:
```ts "schema: rssSchema,"
import { defineCollection } from 'astro:content';
import { rssSchema } from '@astrojs/rss';
const blog = defineCollection({
schema: rssSchema,
});
export const collections = { blog };
```
If you have an existing schema, you can merge extra properties using `extends()`:
```ts ".extends({ extraProperty: z.string() }),"
import { defineCollection } from 'astro:content';
import { rssSchema } from '@astrojs/rss';
const blog = defineCollection({
schema: rssSchema.extends({ extraProperty: z.string() }),
});
```
## `pagesGlobToRssItems()`
To create an RSS feed from documents in `src/pages/`, use the `pagesGlobToRssItems()` helper. This accepts an `import.meta.glob` result ([see Vite documentation](https://vitejs.dev/guide/features.html#glob-import)) and outputs an array of valid [`RSSFeedItem`s](#items).
This function assumes, but does not verify, you are globbing for items inside `src/pages/`, and all necessary feed properties are present in each document's frontmatter. If you encounter errors, verify each page frontmatter manually.
```ts "pagesGlobToRssItems"
// src/pages/rss.xml.js
import rss, { pagesGlobToRssItems } from '@astrojs/rss';
export async function get(context) {
return rss({
title: 'Buzzs Blog',
description: 'A humble Astronauts guide to the stars',
site: context.site,
items: await pagesGlobToRssItems(import.meta.glob('./blog/*.{md,mdx}')),
});
}
```
## `getRssString()`
As `rss()` returns a `Response`, you can also use `getRssString()` to get the RSS string directly and use it in your own response:
```ts "getRssString"
// src/pages/rss.xml.js
import { getRssString } from '@astrojs/rss';
export async function get(context) {
const rssString = await getRssString({
title: 'Buzzs Blog',
...
});
return new Response(rssString, {
headers: {
'Content-Type': 'application/xml',
},
});
}
```
For more on building with Astro, [visit the Astro docs][astro-rss].
[astro-rss]: https://docs.astro.build/en/guides/rss/#using-astrojsrss-recommended
[astro-endpoints]: https://docs.astro.build/en/core-concepts/astro-pages/#non-html-pages