Files
selfpost/docs/plans/panel-notifications.md
T
mixandClaude Opus 5.5 c9027381e5 panel-notifications: guide, architecture, security; refusals looked for every minute
guide.md gains Notifications: the four things, when each is said and said
again, who is told, the two switches, and the two DNS records of the server's
own name that make the mail arrive. architecture.md: the notifier as the
fifth role, its readings, state, recipients and sending; the server's own key
in OpenDKIM's tables; non_smtpd_milters. security.md: the panel submits mail
of its own - how, to whom, and what text from outside can reach a body.

That text - a queued message's sender, a DNS finding - is reduced to
printable ASCII and cut before it is printed. Refused mail is looked for
every minute instead of every five: it is one indexed query, and a refusal is
mail not being sent now. The image's note on the panel's postdrop membership
no longer calls it read-side only.

go test ./internal/notify passes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-12 16:00:06 +03:00

5.6 KiB
Raw Blame History

Plan: panel-notifications

Status: agreed 2026-10-12 - the design questions were closed with the owner and he took it into work ("Делаем")
Date: 2026-10-12
Version: 2.3.0 MINOR (one migration; opt-out by a switch).


Goal

The panel writes to its administrators when something needs them, instead of waiting to be opened.

Decisions (owner, 2026-10-12)

Events of the first version

Four, each of them something the panel can already tell and a person has to act on:

Event Who is told
A sending domain's DNS record stopped matching (SPF, DKIM, DMARC) global users, and domain users the domain is assigned to
A level-2 rate limit refused mail the same, for the domain of the limit
The TLS certificate is about to expire global users
A message has been in the queue for more than three days global users

Three days, not one (owner: "one day is not that much"): Postfix keeps a message five, so two are left to act before it bounces. The threshold is a constant, not a setting.

Left for later: a process or milter socket down (a relay in that state often cannot send), an inbound upstream unreachable, DMARC failures appearing (noisy). Mail held in quarantine is not an event: quarantine is an idea outside the roadmap.

Sender and path

From postmaster@<SELFPOST_HOSTNAME>, submitted locally. Not from one of the sending domains (owner): with several domains the choice is arbitrary, and a message about the certificate has no business coming from a domain.

These messages have to arrive (owner: "we need the best deliverability for them"), so the server's own name gets what a sending domain has:

  • a DKIM key for the hostname, generated by the panel, with which notifications are signed - no domain has to be chosen for it. An SPF record alone would pass DMARC, but not after the user's mailbox forwards the message on, and large receivers treat unsigned mail more strictly;
  • an SPF record for the hostname, v=spf1 a -all.

The records themselves are under Server › Settings (owner: "the DNS records go to Settings, Health has only the status"), in a box of their own drawn with the record component of a domain's DNS page: host, value to publish, copy buttons, state. Server › Health has a card of its own, Notification mail, with the state of each record and a link to Settings. A DMARC record for the hostname is not asked for: the name inherits its parent domain's policy, and with SPF and DKIM aligned it passes any. Without the records notifications are still sent, and the card warns.

Notifications are the panel's own mail: they are not rows of the Outbound log and count against no level-2 limit.

A relay that cannot send cannot say so; none of the four events is "the relay is down", and that is why.

Who chooses what

  • One switch for the instance under Server › Settings.
  • One checkbox per user under Account, "send me notifications" - on when the profile has an e-mail. No choice per event: four events, none of them noise. Per-event choice comes when there are more and some are.
  • A user without an e-mail gets nothing.

When a message is sent

A background check once an hour for DNS, certificate and queue.

Event Sent "Cleared" message
DNS mismatch after two checks in a row found it (it has held for an hour). A resolver that did not answer is not a mismatch after two good checks in a row
Certificate 14 days before expiry, and again 3 days before if it is still the same certificate none
Level-2 limit refused mail at the first refusal for a domain or application, then at most once a day for the same limit none
Queue older than three days when such a message appears one, when none is left

Event state is kept in the database, so a restart announces nothing a second time.

To settle while building

  • How the panel submits: sendmail as the unprivileged panel user, and what that needs of the image.
  • Whether a notification carries a link to the panel - there is no setting for the panel's own address.
  • Where the refusal of a level-2 limit is noticed: in the journal milter as it refuses, or from the rejected rows of the send log on the hourly check.
  • Schema: the user's checkbox, the instance switch, the event state table.

Screens

Not drawn. The Notifications box was taken out of the account and settings mockups on 2026-10-10 (owner: 2.0 ships no box for a feature that is not built). Drawing them again - one checkbox on Account, one switch on Server › Settings, the SPF check on Server › Health - is the first step, shown to the owner before any code (panel-redesign.md § Enforcement).

Implementation checklist

  • Mockups: Account checkbox, Settings switch and records, Health status card, help topic; accepted by the owner 2026-10-12 (design: commit)
  • Migration and store: user flag, instance switch, event state
  • Sending: local submission from postmaster@<hostname>, message text (sendmail as the panel user; signed through non_smtpd_milters with a key of the server's own name; no link in the text - the panel does not know its own address)
  • Background checker: DNS, certificate, queue; the rules of When a message is sent
  • Level-2 refusal event (from the rejected rows of the send log, looked at every minute)
  • Panel: Account, Settings, Health check, help
  • guide.md, architecture.md, security.md, schema-migrations.md
  • go vet, go test, e2e: an event reaches a mailbox once and clears once
  • Technical review
  • Security review