`ReverseConnectListener`

Fully qualified name: PhpOpcua\Client\ExtReverseConnect\ReverseConnectListener.

Constructor

public function __construct(
    string $bindHost,
    int $bindPort,
    ReverseHelloValidator $validator,
    ?LoggerInterface $logger = null,
    ?EventDispatcherInterface $dispatcher = null,
    int $maxFrameSize = ReverseHelloParser::DEFAULT_MAX_FRAME_SIZE,
)

Methods

listen(): void

Opens the TCP server socket on bindHost:bindPort. Idempotent — a second call without a close() in between is a no-op. Raises ReverseConnectException if the kernel-level stream_socket_server() fails (port already bound, permission denied, …) with a message of the form Failed to bind reverse-connect listener on ….

getBindAddress(): string

Returns the actual bound address — host:port, with port the kernel-assigned value when the constructor was called with 0. Raises ReverseConnectException if called before listen().

isListening(): bool

true between listen() and the next close(). false before listen() and after close().

accept(float $timeoutSeconds): ReverseConnectSession

Block until a server connects and a full RHE frame arrives, validate it, and return a ReverseConnectSession. The budget covers both the inbound TCP connection and the frame read.

Sequence of side effects on success:

1. stream_select() returns ready.
2. stream_socket_accept() produces a socket.
3. stream_set_timeout() is applied to the accepted socket with the integer part of $timeoutSeconds, clamped to a minimum of 1.
4. The RHE frame is decoded via ReverseHelloParser::parse().
5. ReverseHelloReceived is dispatched (if a dispatcher was provided).
6. The validator is invoked.
7. ReverseConnectAccepted is dispatched on success.
8. The session is returned.

Errors are reported by exception, in this order:

On every error path that already accepted the socket, the listener closes the socket before raising the exception, and dispatches ReverseConnectRejected for whitelist failures.

close(): void

Closes the listener socket. Safe to call multiple times. Does not close sockets returned by previous accept() calls — those are owned by their respective sessions.

Logging

When a logger is configured the listener emits:

• INFO Reverse-connect listener bound with address context after listen() succeeds.
• INFO ReverseHello accepted with serverUri and endpointUrl context on every successful accept().
• WARNING ReverseHello rejected by validator with serverUri, endpointUrl, and reason context.
• WARNING ReverseHello parse failed with error context.

Events

See Events for the three PSR-14 events the listener dispatches.

Concurrency

The listener is single-threaded and not safe for concurrent use. To service multiple servers, call accept() serially in a loop, or operate multiple listener instances on different ports.