Files
SciMesh/coordinator/internal/infra/server.go
T
Efremenko Arhip 3b41455b20 feat(coordinator): running state, worker liveness, request-size limits
Polish pass hardening the queue and closing plan gaps.

- Task state machine gains `running`: the first heartbeat moves a task from
  leased to running (migrations 0006/0007 add the enum value and extend the
  lease-integrity check). verifyLease, ExpireLease, the reaper SQL, and job
  progress all treat leased and running alike.
- Worker liveness: a heartbeat from a registered worker (UUID worker_id) bumps
  its last_heartbeat_at online; a second background reaper marks workers offline
  after WORKER_OFFLINE_AFTER of silence (RunReaper generalized to RunPeriodic).
- Request-size limits: JSON bodies capped at 1 MiB; dataset/artifact uploads
  capped at MAX_UPLOAD_BYTES (default 1 GiB) via http.MaxBytesReader.
- Tests cover the running transition, liveness + offline reaper (unit over
  memstore and integration over Postgres).
2026-07-23 17:36:26 +03:00

75 lines
2.0 KiB
Go

// Server: the HTTP listener and the background lease reaper, both shut down
// cleanly on a signal.
package infra
import (
"context"
"errors"
"log/slog"
"net/http"
"time"
)
const shutdownGrace = 15 * time.Second
// Run serves handler until ctx is cancelled, then drains in-flight requests.
func RunServer(ctx context.Context, log *slog.Logger, addr string, handler http.Handler) error {
srv := &http.Server{
Addr: addr,
Handler: handler,
ReadHeaderTimeout: 5 * time.Second,
}
// Buffered so this goroutine can exit even when nobody reads the channel
// (the ctx.Done branch below) — an unbuffered send would leak it forever.
errCh := make(chan error, 1)
go func() {
log.Info("coordinator listening", "addr", addr)
if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
errCh <- err
}
}()
select {
case err := <-errCh:
return err
case <-ctx.Done():
log.Info("shutdown signal received")
}
// A fresh context: ctx is already cancelled, and reusing it would abort the
// very requests we are trying to let finish.
shutdownCtx, cancel := context.WithTimeout(context.Background(), shutdownGrace)
defer cancel()
return srv.Shutdown(shutdownCtx)
}
// RunReaper periodically reclaims tasks whose lease elapsed, so a worker that
// died without a heartbeat cannot strand its task in 'leased' forever.
// RunPeriodic invokes fn on an interval until ctx is done, logging how many rows
// each tick affected. It backs the background reapers (expired leases, offline
// workers) — each is a set-based UPDATE that is safe to run repeatedly and
// concurrently across coordinators.
func RunPeriodic(ctx context.Context, log *slog.Logger, name string, interval time.Duration,
fn func(context.Context) (int64, error)) {
t := time.NewTicker(interval)
defer t.Stop()
for {
select {
case <-ctx.Done():
return
case <-t.C:
n, err := fn(ctx)
if err != nil {
log.Debug(name+" skipped", "err", err)
continue
}
if n > 0 {
log.Info(name, "count", n)
}
}
}
}