Feeds and sitemap

MapOsirionFeeds maps three endpoints built from the published content of your content providers: an XML sitemap at /sitemap.xml, an RSS 2.0 feed at /feed.xml and an Atom 1.0 feed at /atom.xml. Search engines read the sitemap; feed readers subscribe to either feed.

Available from 4.1.

Usage

Call it in Program.cs after the content services are registered:

using Osirion.Blazor.Cms.Web.Feeds;

app.MapOsirionFeeds(feeds =>
{
    feeds.SiteUrl = "https://example.com";
    feeds.FeedDirectory = "blog";
    feeds.AdditionalSitemapUrls = ["/", "/blog"];
});

With no arguments, app.MapOsirionFeeds() maps all three endpoints over all content and builds URLs from the request.

OsirionFeedOptions

The options are checked when MapOsirionFeeds runs: a SiteUrl that is not an absolute http or https URL throws ArgumentException, and a FeedItemCount below 1 throws ArgumentOutOfRangeException, so a bad value stops the application at startup instead of producing broken feeds.

What goes into each document

• Sitemap. Each URL has a lastmod from the item's last_modified front matter, then the file's write time (file system provider), then its date. Set last_modified when dates must survive a fresh checkout or a new deployment. Items whose seo_properties.robots contains noindex are left out, and duplicate URLs are written once. The sitemap covers all content; FeedDirectory and FeedLocale do not apply to it.
• RSS. Each item has its title, link, a permalink guid, pubDate from date and the description front matter. The channel carries an atom:link rel="self" pointing to /feed.xml.
• Atom. Each entry has an id (its URL), title, link, published, updated, the author when set, and the description as its summary. The feed-level author is the feed title, which satisfies Atom's rule that every entry has an author.
• Feeds carry descriptions, not full article bodies. Unpublished items (published: false) never appear.
• Characters that XML cannot represent are dropped from titles and descriptions rather than failing the request.

Security and caching

Set SiteUrl in production. Without it, URLs follow whatever Host header a request sends, so a forged header could put another host into a response that a cache or crawler stores. Responses are marked public, so browsers and shared caches may keep serving a document for up to CacheDuration after the content changes.

Pointing crawlers and readers at them

Add the sitemap to your robots.txt:

Sitemap: https://example.com/sitemap.xml

Let browsers and feed readers discover the feeds from the page head, for example in App.razor:

<link rel="alternate" type="application/rss+xml" title="Example blog" href="/feed.xml" />
<link rel="alternate" type="application/atom+xml" title="Example blog" href="/atom.xml" />

Related

• SeoMetadataRenderer: head metadata; its SiteName and SiteDescription options also title the feeds
• ContentList: the list pages whose links the feeds share
• CMS Web core components