This server exposes a webhook notification. When called, it will scan the configured site for new links to third-party sites, check if those sites are receptive to webmentions, and for ones that are dispatches mentions to them. Mentions which have been sent are kept in a local database so that mentions aren't sent more than once.

To use this yourself, remix this glitch and update these fields in package.json:

• baseUrl: The base URL of your blog, including the protocol and domain (and not a path).
• denyList: A list of regular expressions for URLs to ignore. URLs which begin with baseUrl or are relative will be automatically ignored.
• postPattern: A regular expression to match URLs of your site which are blog entries.

Links in webmentions should be omitted. Add a class to each anchor tag in a webmention of webmention to filter them out.

This glitch assumes that you have a /sitemap.txt, and it uses this to determine a list of blog entries to process.

This glitch also assumes that your posts have a <time> element with a class including dt-published in it, and that posts with updates have a second <time> element with a class including dt-updated. It uses these to go through the following process for each new blog post:

• A request is made for the post. The ETag is taken from the headers, and the dt-published and dt-updated are extracted from the both. If the latter is not found it defaults to the same value as dt-published. These are stored.
• URLs are extracted and filtered according to the denyList and the baseUrl.
• This glitch attempts to dispatch a mention for each remaining URL. When an endpoint was found for a URL and the dispatch successful, this glitch stores a record of the mention so that it doesn't get resent in the future.

For an existing blog post:

• A request is made for the post. The ETag is taken from the headers. If this ETag matches the one stored, then no further processing occurs.
• The body is processed for a <time> element with dt-updated. If the element is not found or the value of it has not changed, then no futher processing occurs and the ETag stored by this glitch for the post is updated.
• URLs are extracted and filtered according to the denyList and the baseUrl. Any URLs matching existing mentions for this post are also filtered out.
• This glitch attempts to dispatch a mention for each remaining URL, storing successful mentions to avoid dispatching them again in the future. The ETag and update time stored for the post are updated.