stead from pg

sql.go

@@ -0,0 +1,71 @@
+package with
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"log"
+	"net/url"
+	"time"
+
+	_ "modernc.org/sqlite"
+)
+
+func SQL(ctx context.Context, conn string, foo func(*sql.DB) error) error {
+	u, err := url.Parse(conn)
+	if err != nil {
+		return err
+	}
+	switch u.Scheme {
+	case "sqlite":
+		return Sqlite(ctx, conn, foo)
+	case "postgres", "postgresql":
+		return PSQL(ctx, conn, foo)
+	}
+	return fmt.Errorf("unknown sql scheme %q", u.Scheme)
+}
+
+func _sql(ctx context.Context, engine, conn string, foo func(db *sql.DB) error) error {
+	log.Printf("opening %s %s...", engine, conn)
+	db, err := sql.Open(engine, conn)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		log.Println("closed:", db.Close())
+	}()
+
+	func() {
+		pinged := make(chan bool)
+		defer close(pinged)
+		for {
+			log.Println("pinging...")
+			go func() {
+				err := db.PingContext(ctx)
+				if err != nil {
+					log.Println("!", err)
+				}
+				select {
+				case pinged <- err == nil:
+				case <-ctx.Done():
+				case <-time.After(time.Second * 5):
+				}
+			}()
+			select {
+			case <-ctx.Done():
+				return
+			case ok := <-pinged:
+				if ok {
+					return
+				}
+			}
+			select {
+			case <-ctx.Done():
+			case <-time.After(time.Second):
+			}
+		}
+	}()
+	log.Println("connected")
+
+	return foo(db)
+}