+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
package main
import (
}
type pgEventSource struct {
- DataSource string
- QueueSize int
+ DataSource string
+ MaxOpenConns int
+ QueueSize int
db *sql.DB
pqListener *pq.Listener
eventsOut uint64
cancel func()
+
+ setupOnce sync.Once
+ ready chan bool
}
var _ debugStatuser = (*pgEventSource)(nil)
ps.cancel()
}
+func (ps *pgEventSource) setup() {
+ ps.ready = make(chan bool)
+}
+
+// Close stops listening for new events and disconnects all clients.
+func (ps *pgEventSource) Close() {
+ ps.WaitReady()
+ ps.cancel()
+}
+
+// WaitReady returns when the event listener is connected.
+func (ps *pgEventSource) WaitReady() {
+ ps.setupOnce.Do(ps.setup)
+ <-ps.ready
+}
+
// Run listens for event notifications on the "logs" channel and sends
// them to all subscribers.
func (ps *pgEventSource) Run() {
logger(nil).Debug("pgEventSource Run starting")
defer logger(nil).Debug("pgEventSource Run finished")
+ ps.setupOnce.Do(ps.setup)
+ ready := ps.ready
+ defer func() {
+ if ready != nil {
+ close(ready)
+ }
+ }()
+
ctx, cancel := context.WithCancel(context.Background())
ps.cancel = cancel
defer cancel()
db, err := sql.Open("postgres", ps.DataSource)
if err != nil {
- logger(nil).WithError(err).Fatal("sql.Open failed")
+ logger(nil).WithError(err).Error("sql.Open failed")
return
}
+ if ps.MaxOpenConns <= 0 {
+ logger(nil).Warn("no database connection limit configured -- consider setting PostgresPool>0 in arvados-ws configuration file")
+ }
+ db.SetMaxOpenConns(ps.MaxOpenConns)
if err = db.Ping(); err != nil {
- logger(nil).WithError(err).Fatal("db.Ping failed")
+ logger(nil).WithError(err).Error("db.Ping failed")
return
}
ps.db = db
ps.pqListener = pq.NewListener(ps.DataSource, time.Second, time.Minute, ps.listenerProblem)
err = ps.pqListener.Listen("logs")
if err != nil {
- logger(nil).WithError(err).Fatal("pq Listen failed")
+ logger(nil).WithError(err).Error("pq Listen failed")
+ return
}
defer ps.pqListener.Close()
logger(nil).Debug("pq Listen setup done")
+ close(ready)
+ // Avoid double-close in deferred func
+ ready = nil
+
ps.queue = make(chan *event, ps.QueueSize)
defer close(ps.queue)
}
func (ps *pgEventSource) DB() *sql.DB {
+ ps.WaitReady()
return ps.db
}
+func (ps *pgEventSource) DBHealth() error {
+ ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(time.Second))
+ defer cancel()
+ var i int
+ return ps.db.QueryRowContext(ctx, "SELECT 1").Scan(&i)
+}
+
func (ps *pgEventSource) DebugStatus() interface{} {
ps.mtx.Lock()
defer ps.mtx.Unlock()
"QueueDelay": stats.Duration(ps.lastQDelay),
"Sinks": len(ps.sinks),
"SinksBlocked": blocked,
+ "DBStats": ps.db.Stats(),
}
}
// Ensure this sink cannot fill up and block the
// server-side queue (which otherwise could in turn
// block our mtx.Lock() here)
- for _ = range sink.channel {
+ for range sink.channel {
}
}()
sink.source.mtx.Lock()