jackc/pgx · error

expected AuthenticationSASLFinal message but received unexpe

Error message

expected AuthenticationSASLFinal message but received unexpected message %T

What it means

Error "expected AuthenticationSASLFinal message but received unexpected message %T" thrown in jackc/pgx.

Source

Thrown at pgconn/auth_scram.go:141

		return nil, ErrorResponseToPgError(m)
	}

	return nil, fmt.Errorf("expected AuthenticationSASLContinue message but received unexpected message %T", msg)
}

func (c *PgConn) rxSASLFinal() (*pgproto3.AuthenticationSASLFinal, error) {
	msg, err := c.receiveMessage()
	if err != nil {
		return nil, err
	}
	switch m := msg.(type) {
	case *pgproto3.AuthenticationSASLFinal:
		return m, nil
	case *pgproto3.ErrorResponse:
		return nil, ErrorResponseToPgError(m)
	}

	return nil, fmt.Errorf("expected AuthenticationSASLFinal message but received unexpected message %T", msg)
}

type scramClient struct {
	serverAuthMechanisms []string
	password             string
	clientNonce          []byte

	// authMechanism is the selected SASL mechanism for the client. Must be
	// either SCRAM-SHA-256 (default) or SCRAM-SHA-256-PLUS.
	//
	// Upgraded to SCRAM-SHA-256-PLUS during authentication when channel binding
	// is not disabled, channel binding data is available (TLS connection with
	// an obtainable server certificate hash) and the server advertises
	// SCRAM-SHA-256-PLUS.
	authMechanism string

	// hasTLS indicates whether the connection is using TLS. This is
	// needed because the GS2 header must distinguish between a client that

View on GitHub (pinned to ec1a0befd2)

When it happens

Trigger: Thrown at pgconn/auth_scram.go:141 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of jackc/pgx@ec1a0befd2 (2026-08-04). Data as JSON: /data/errors/11fcff33da22836a.json. Report an issue: GitHub.