Bluesky renders no link card of its own. Its PDS never fetches the page
behind a URL, so a post whose record has no app.bsky.embed.external
shows the link as bare text; every client that shows a card builds it
before posting. We only built one for YouTube, so every other link
arrived on bluesky with nothing attached.
preview.go now reads the Open Graph tags of an ordinary page and turns
them into the same card: og:title and og:description, falling back to
the twitter:* tags and then to <title> and meta description, with
og:image fetched as the thumbnail. YouTube keeps its oEmbed path, which
answers with the handful of fields a card needs rather than the megabyte
of markup the watch page is.
Only the head of a page is read, and parsing stops at <body>, since
preview tags belong above it and a truncated page still yields what was
read. Pages are decoded through x/net/html/charset rather than assumed
to be UTF-8, which Japanese pages served as Shift_JIS are not. The
thumbnail is resolved against the URL the body came from, so a relative
og:image survives a redirect. Requests now name the bot in a User-Agent,
which some sites want before serving preview tags at all.
fetch grew a byte limit and now reports the media type and final URL its
body came with, which is what the thumbnail needs to name and resolve
itself.
Checked against go.dev, Japanese Wikipedia and a YouTube video.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Deleting a message on the watched channel now deletes the posts it
produced. Making that possible reshapes how a message reaches an output:
- OutputInterface takes an output.Post and returns an output.Ref, the
identifier the platform gave the new post (tweet ID for X, URI and
CID for bluesky). It also gained Delete(Ref).
- The discord package no longer forwards raw MessageCreate values but
a discord.Event carrying the kind of change, so the MessageDelete
handler can use the same channel. Deleted messages arrive without an
author, so only the channel ID can be filtered on.
- The new store package remembers Discord message ID -> per output Ref.
Set POST_STORE to a path to keep that mapping across restarts;
without it the mapping is memory only and a restart makes older
messages undeletable. It holds the most recent 1000 messages.
main.go grows a distributor type to hold the outputs and the store
rather than threading them through the event loop.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
