Files
selfpost/cmd/panel/main.go
T
mix ed9e942e42 Phase 1: Docker image, supervisord, three-process cold start
Single bookworm-slim image running opendkim + panel + postfix under
supervisord with enforced start ordering (spec 4):

- build/Dockerfile: multi-stage static Go build; runtime installs postfix,
  opendkim, cyrus-sasl, supervisor, logrotate; unprivileged panel user (7.6.8).
- build/supervisord.conf: priority ordering opendkim -> panel -> postfix;
  crashexit event listener terminates the container on any FATAL process.
- build/postfix-wrapper.sh: waits for both milter sockets (test -S, 30s
  timeout) before `postfix start-fg`, exits non-zero on timeout.
- panel: HTTP :8080 stub + /healthz, journal-milter socket stub (so the
  wrapper's readiness probe passes), log-tailer stub; SIGTERM graceful stop.

Verified on the dev server: image builds, three processes live, panel serves
the stub, wrapper waits for sockets, and an unrecoverable panel failure brings
the container down cleanly.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-11 15:14:08 +03:00

110 lines
2.9 KiB
Go

// Command panel is the SelfPost control panel. In the finished product this
// single binary combines several roles (spec 7.1): the HTTP panel server,
// the journal-milter, the mail.log tailer and the rate-limit checks.
//
// Phase 1 wires those roles up as a supervised process with a minimal HTTP
// stub, a journal-milter socket stub (so the Postfix start wrapper's readiness
// probe passes) and a log-tailer stub. Real behaviour lands in later phases.
package main
import (
"context"
"flag"
"fmt"
"log"
"os"
"os/signal"
"sync"
"syscall"
"codeberg.org/mix/selfpost/internal/buildinfo"
)
func main() {
showVersion := flag.Bool("version", false, "print version and exit")
flag.Parse()
if *showVersion {
fmt.Println(buildinfo.Version)
return
}
log.SetFlags(log.LstdFlags | log.LUTC)
log.SetPrefix("panel: ")
if err := run(); err != nil {
log.Fatalf("fatal: %v", err)
}
}
// config holds the runtime knobs the panel reads from the environment. Every
// value has a safe default so the binary also runs outside the container.
type config struct {
httpAddr string
journalSocket string
mailLog string
}
func loadConfig() config {
return config{
httpAddr: envDefault("PANEL_HTTP_ADDR", ":8080"),
journalSocket: envDefault("JOURNAL_MILTER_SOCKET", "/run/selfpost/journal.sock"),
mailLog: envDefault("MAIL_LOG", "/var/log/mail.log"),
}
}
func envDefault(key, def string) string {
if v := os.Getenv(key); v != "" {
return v
}
return def
}
// run starts the panel's three roles and blocks until a shutdown signal or the
// first fatal error from any role. A signal triggers a clean stop of all roles;
// a role error cancels the others and is returned so the process exits non-zero
// (letting supervisord/Docker see the failure — spec 4).
func run() error {
cfg := loadConfig()
ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
defer stop()
log.Printf("starting selfpost panel %s", buildinfo.Version)
var wg sync.WaitGroup
errc := make(chan error, 3)
roles := []struct {
name string
fn func(context.Context) error
}{
{"http", func(ctx context.Context) error { return serveHTTP(ctx, cfg.httpAddr) }},
{"journal-milter", func(ctx context.Context) error { return serveJournalStub(ctx, cfg.journalSocket) }},
{"log-tailer", func(ctx context.Context) error { return tailMailLog(ctx, cfg.mailLog) }},
}
for _, r := range roles {
wg.Add(1)
go func(name string, fn func(context.Context) error) {
defer wg.Done()
if err := fn(ctx); err != nil {
errc <- fmt.Errorf("%s: %w", name, err)
}
}(r.name, r.fn)
}
select {
case <-ctx.Done():
log.Printf("shutdown signal received, stopping")
wg.Wait()
log.Printf("panel stopped cleanly")
return nil
case err := <-errc:
log.Printf("role failed: %v", err)
stop() // cancel ctx so the other roles wind down
wg.Wait()
return err
}
}