added select auto fail/retry

daos/base_retry.go

@@ -0,0 +1,58 @@
+package daos
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"github.com/pocketbase/dbx"
+)
+
+const defaultQueryTimeout time.Duration = 2 * time.Minute
+
+const defaultMaxRetries int = 10
+
+var defaultRetryIntervals = []int{100, 250, 350, 500, 700, 1000, 1200, 1500}
+
+func onLockErrorRetry(s *dbx.SelectQuery, op func() error) error {
+	return baseLockRetry(func(attempt int) error {
+		// load a default timeout context if not set explicitly
+		if s.Context() == nil {
+			ctx, cancel := context.WithTimeout(context.Background(), defaultQueryTimeout)
+			defer func() {
+				cancel()
+				s.WithContext(nil) // reset
+			}()
+			s.WithContext(ctx)
+		}
+
+		return op()
+	}, defaultMaxRetries)
+}
+
+func baseLockRetry(op func(attempt int) error, maxRetries int) error {
+	attempt := 1
+
+Retry:
+	err := op(attempt)
+
+	if err != nil &&
+		attempt <= maxRetries &&
+		// we are checking the err message to handle both the cgo and noncgo errors
+		strings.Contains(err.Error(), "database is locked") {
+		// wait and retry
+		time.Sleep(getDefaultRetryInterval(attempt))
+		attempt++
+		goto Retry
+	}
+
+	return err
+}
+
+func getDefaultRetryInterval(attempt int) time.Duration {
+	if attempt < 0 || attempt > len(defaultRetryIntervals)-1 {
+		return time.Duration(defaultRetryIntervals[len(defaultRetryIntervals)-1]) * time.Millisecond
+	}
+
+	return time.Duration(defaultRetryIntervals[attempt]) * time.Millisecond
+}