After-edit hooks

const Document = entity(
  "Document",
  { title: field.string(), body: field.richtext().crdt("prosemirror") },
  { afterEdit: { fn: "indexDocument", delaySeconds: 5 } },
);

// functions/indexDocument.ts
import { mutation, v } from "@pylonsync/functions";

export default mutation({
  internal: true,
  args: { id: v.string() },
  async handler(ctx, args) {
    const doc = await ctx.db.get("Document", args.id);
    if (!doc) return; // deleted since the edit
    // ...update a search index, a preview, a review queue...
  },
});

​

When it runs

• The function gets { id } and reads the row itself. The row may have changed again, or been deleted, by the time it runs.
• It must be internal: true. It runs without a user, like a cron target; its ctx.db calls are server-side.
• Runs are jobs on the functions queue: they survive a restart, retry when the function throws, and show in pylon jobs. On Postgres the job id names the row and the window, so the writes of every machine share one run.
• Each write notes its run in the same database transaction as the row, so a committed write always gets its run (and a rolled-back one never does), even when the server stops right after the write.