feat: PostgreSQL as the panel's database, chosen in Настройки, the SQLite data copied over on its first start; tested on a real PostgreSQL

internal/server/dbpg.go

@@ -167,16 +167,22 @@ func copyDB(src, dst *DB) error {
 			return err
 		}
 	}
+	if err := tx.Commit(); err != nil {
+		return err
+	}
+	// The id counters past the copied ids, where a table has one.
 	for _, t := range copyTables {
 		var seq sql.NullString
-		_ = tx.QueryRow(`SELECT pg_get_serial_sequence($1, 'id')`, t).Scan(&seq)
-		if seq.Valid {
-			if _, err := tx.Exec(`SELECT setval($1, COALESCE((SELECT MAX(id) FROM `+t+`), 0) + 1, false)`, seq.String); err != nil {
-				return err
-			}
+		err := dst.sql.DB.QueryRow(`SELECT pg_get_serial_sequence($1, column_name) FROM information_schema.columns
+			WHERE table_name = $1 AND column_name = 'id' AND column_default LIKE 'nextval%'`, t).Scan(&seq)
+		if err != nil || !seq.Valid {
+			continue
+		}
+		if _, err := dst.sql.DB.Exec(`SELECT setval($1, COALESCE((SELECT MAX(id) FROM `+t+`), 0) + 1, false)`, seq.String); err != nil {
+			return err
 		}
 	}
-	return tx.Commit()
+	return nil
 }
 
 // Backend tells which database is in use and which is chosen for the next

internal/server/dbpg_test.go

@@ -0,0 +1,85 @@
+package server
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+
+	"github.com/x-grk/longpolling-remote-access/internal/proto"
+)
+
+// On a real PostgreSQL (LPRA_TEST_PG: {"host","port","name","user","password",
+// "sslmode"} of an empty database): the first start copies the SQLite data
+// over, and the panel's queries work there.
+func TestPostgres(t *testing.T) {
+	raw := os.Getenv("LPRA_TEST_PG")
+	if raw == "" {
+		t.Skip("LPRA_TEST_PG not set")
+	}
+	var c PGConf
+	if err := json.Unmarshal([]byte(raw), &c); err != nil {
+		t.Fatal(err)
+	}
+	// SQLite with a user, a machine, a rule, a saved host and some talk.
+	s, _ := newTestServer(t)
+	a, _ := s.db.AdminByUsername("adm")
+	if _, err := s.db.CreateForwardRule(ForwardRule{AgentID: "x1", ClientPort: 80, HostPort: 18080, ListenAddr: "0.0.0.0", Proto: "tcp", NoUfw: true}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := s.saveSSHHost(a.ID, savedHost{Label: "web", Host: "h", Port: 22, User: "root", Auth: "password"}, sshSecret{Password: "pw"}); err != nil {
+		t.Fatal(err)
+	}
+	s.aiAppend(a.ID, "user", "привет")
+	_ = s.db.SetUserAgents(a.ID, []string{"x1"})
+
+	pg, err := OpenPostgres(c, s.db.path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer pg.Close()
+	// Clean up for the next run.
+	defer func() {
+		for i := len(copyTables) - 1; i >= 0; i-- {
+			_, _ = pg.sql.Exec(`DROP TABLE IF EXISTS ` + copyTables[i] + ` CASCADE`)
+		}
+	}()
+	p := &Server{db: pg}
+	if got, _ := pg.AdminByUsername("adm"); got == nil || got.ID != a.ID {
+		t.Fatalf("admin not copied: %+v", got)
+	}
+	if ag, _ := pg.GetAgent("x1"); ag == nil {
+		t.Fatal("agent not copied")
+	}
+	rules, _ := pg.ListForwardRules()
+	if len(rules) != 1 || !rules[0].NoUfw {
+		t.Fatalf("rules: %+v", rules)
+	}
+	tg := &proto.SSHTarget{Saved: p.listSSHHosts(a.ID)[0].ID}
+	if err := p.fillSaved(a.ID, tg); err != nil || tg.Password != "pw" {
+		t.Fatalf("saved host: %+v %v", tg, err)
+	}
+	if h := p.aiHistory(a.ID, 10); len(h) != 1 || h[0].Content != "привет" {
+		t.Fatalf("talk: %+v", h)
+	}
+	// New rows go on after the copied ids.
+	id, err := pg.CreateUser("bob", "x", RoleUser)
+	if err != nil || id <= a.ID {
+		t.Fatalf("new user id %d, %v", id, err)
+	}
+	if err := pg.SetConfig("k", "v1"); err != nil {
+		t.Fatal(err)
+	}
+	if err := pg.SetConfig("k", "v2"); err != nil {
+		t.Fatal(err)
+	}
+	if v, _ := pg.GetConfig("k"); v != "v2" {
+		t.Fatalf("config upsert: %q", v)
+	}
+	if err := pg.SetUserAgents(id, []string{"x1", "x1"}); err != nil {
+		t.Fatalf("grants: %v", err)
+	}
+	p.aiAppend(a.ID, "assistant", "ответ")
+	if h := p.aiHistory(a.ID, 10); len(h) != 2 {
+		t.Fatalf("talk after: %+v", h)
+	}
+}