golang-migrate/migrate · error

no config

Error message

no config

What it means

The CockroachDB driver defines ErrNilConfig ("no config") and returns it from WithInstance, WithConnection, and extractCustomQueryParams when the *Config pointer is nil. Without a config the driver cannot determine migrations table, lock table, or database name, so construction is refused.

Source

Thrown at database/cockroachdb/cockroachdb.go:31

	"github.com/cockroachdb/cockroach-go/v2/crdb"
	"github.com/golang-migrate/migrate/v4"
	"github.com/golang-migrate/migrate/v4/database"
	"github.com/lib/pq"
)

func init() {
	db := CockroachDb{}
	database.Register("cockroach", &db)
	database.Register("cockroachdb", &db)
	database.Register("crdb-postgres", &db)
}

var DefaultMigrationsTable = "schema_migrations"
var DefaultLockTable = "schema_lock"

var (
	ErrNilConfig      = fmt.Errorf("no config")
	ErrNoDatabaseName = fmt.Errorf("no database name")
)

type Config struct {
	MigrationsTable string
	LockTable       string
	ForceLock       bool
	DatabaseName    string
}

type CockroachDb struct {
	db       *sql.DB
	isLocked atomic.Bool

	// Open and WithInstance need to guarantee that config is never nil
	config *Config
}

View on GitHub (pinned to 01a9643f14)

Solutions

1. Build the driver via cockroachdb.WithURL("cockroachdb://user:pass@host:26257/db?sslmode=disable") so a populated Config is created.
2. Or pass a populated &cockroachdb.Config{MigrationsTable: ..., DatabaseName: ...} to WithInstance/WithConnection.
3. Guard the call site: if cfg == nil { return nil, errors.New("cockroachdb config required") } before invoking the library.

Example fix

// before
d, err := cockroachdb.WithInstance(db, nil)
// after
d, err := cockroachdb.WithURL("cockroachdb://root@localhost:26257/migrations?sslmode=disable")

if cfg == nil {
    return fmt.Errorf("cockroachdb config must not be nil")
}
if cfg.DatabaseName == "" {
    return fmt.Errorf("cockroachdb config requires a database name")
}

func validCockroachConfig(cfg *cockroachdb.Config) bool {
    return cfg != nil && cfg.DatabaseName != ""
}

d, err := cockroachdb.WithInstance(db, cfg)
if err != nil {
    if errors.Is(err, cockroachdb.ErrNilConfig) {
        return fmt.Errorf("use cockroachdb.WithURL or pass a populated *cockroachdb.Config")
    }
    return err
}

When it happens

Trigger: Calling cockroachdb.WithInstance(conn, nil), cockroachdb.WithConnection(conn, nil), or extractCustomQueryParams with a nil config.

Common situations: Skipping cockroachdb.WithURL / Open and wiring the driver by hand; a nil config returned from an earlier failed parse; uninitialized struct pointer in a DI container.

Related errors

• no config
• no database name
• no database name
• no config
• no keyspace provided

AI-assisted analysis of golang-migrate/migrate@01a9643f14 (2026-09-02). Data as JSON: /api/errors/febf56fd4095bb48. Report an issue: GitHub.