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diff --git a/assets/php/vendor/react/socket/README.md b/assets/php/vendor/react/socket/README.md new file mode 100644 index 0000000..e8b53a0 --- /dev/null +++ b/assets/php/vendor/react/socket/README.md @@ -0,0 +1,1419 @@ +# Socket + +[](https://travis-ci.org/reactphp/socket) + +Async, streaming plaintext TCP/IP and secure TLS socket server and client +connections for [ReactPHP](https://reactphp.org/). + +The socket library provides re-usable interfaces for a socket-layer +server and client based on the [`EventLoop`](https://github.com/reactphp/event-loop) +and [`Stream`](https://github.com/reactphp/stream) components. +Its server component allows you to build networking servers that accept incoming +connections from networking clients (such as an HTTP server). +Its client component allows you to build networking clients that establish +outgoing connections to networking servers (such as an HTTP or database client). +This library provides async, streaming means for all of this, so you can +handle multiple concurrent connections without blocking. + +**Table of Contents** + +* [Quickstart example](#quickstart-example) +* [Connection usage](#connection-usage) + * [ConnectionInterface](#connectioninterface) + * [getRemoteAddress()](#getremoteaddress) + * [getLocalAddress()](#getlocaladdress) +* [Server usage](#server-usage) + * [ServerInterface](#serverinterface) + * [connection event](#connection-event) + * [error event](#error-event) + * [getAddress()](#getaddress) + * [pause()](#pause) + * [resume()](#resume) + * [close()](#close) + * [Server](#server) + * [Advanced server usage](#advanced-server-usage) + * [TcpServer](#tcpserver) + * [SecureServer](#secureserver) + * [UnixServer](#unixserver) + * [LimitingServer](#limitingserver) + * [getConnections()](#getconnections) +* [Client usage](#client-usage) + * [ConnectorInterface](#connectorinterface) + * [connect()](#connect) + * [Connector](#connector) + * [Advanced client usage](#advanced-client-usage) + * [TcpConnector](#tcpconnector) + * [DnsConnector](#dnsconnector) + * [SecureConnector](#secureconnector) + * [TimeoutConnector](#timeoutconnector) + * [UnixConnector](#unixconnector) + * [FixUriConnector](#fixeduriconnector) +* [Install](#install) +* [Tests](#tests) +* [License](#license) + +## Quickstart example + +Here is a server that closes the connection if you send it anything: + +```php +$loop = React\EventLoop\Factory::create(); +$socket = new React\Socket\Server('127.0.0.1:8080', $loop); + +$socket->on('connection', function (ConnectionInterface $conn) { + $conn->write("Hello " . $conn->getRemoteAddress() . "!\n"); + $conn->write("Welcome to this amazing server!\n"); + $conn->write("Here's a tip: don't say anything.\n"); + + $conn->on('data', function ($data) use ($conn) { + $conn->close(); + }); +}); + +$loop->run(); +``` + +See also the [examples](examples). + +Here's a client that outputs the output of said server and then attempts to +send it a string: + +```php +$loop = React\EventLoop\Factory::create(); +$connector = new React\Socket\Connector($loop); + +$connector->connect('127.0.0.1:8080')->then(function (ConnectionInterface $conn) use ($loop) { + $conn->pipe(new React\Stream\WritableResourceStream(STDOUT, $loop)); + $conn->write("Hello World!\n"); +}); + +$loop->run(); +``` + +## Connection usage + +### ConnectionInterface + +The `ConnectionInterface` is used to represent any incoming and outgoing +connection, such as a normal TCP/IP connection. + +An incoming or outgoing connection is a duplex stream (both readable and +writable) that implements React's +[`DuplexStreamInterface`](https://github.com/reactphp/stream#duplexstreaminterface). +It contains additional properties for the local and remote address (client IP) +where this connection has been established to/from. + +Most commonly, instances implementing this `ConnectionInterface` are emitted +by all classes implementing the [`ServerInterface`](#serverinterface) and +used by all classes implementing the [`ConnectorInterface`](#connectorinterface). + +Because the `ConnectionInterface` implements the underlying +[`DuplexStreamInterface`](https://github.com/reactphp/stream#duplexstreaminterface) +you can use any of its events and methods as usual: + +```php +$connection->on('data', function ($chunk) { + echo $chunk; +}); + +$connection->on('end', function () { + echo 'ended'; +}); + +$connection->on('error', function (Exception $e) { + echo 'error: ' . $e->getMessage(); +}); + +$connection->on('close', function () { + echo 'closed'; +}); + +$connection->write($data); +$connection->end($data = null); +$connection->close(); +// … +``` + +For more details, see the +[`DuplexStreamInterface`](https://github.com/reactphp/stream#duplexstreaminterface). + +#### getRemoteAddress() + +The `getRemoteAddress(): ?string` method returns the full remote address +(URI) where this connection has been established with. + +```php +$address = $connection->getRemoteAddress(); +echo 'Connection with ' . $address . PHP_EOL; +``` + +If the remote address can not be determined or is unknown at this time (such as +after the connection has been closed), it MAY return a `NULL` value instead. + +Otherwise, it will return the full address (URI) as a string value, such +as `tcp://127.0.0.1:8080`, `tcp://[::1]:80`, `tls://127.0.0.1:443`, +`unix://example.sock` or `unix:///path/to/example.sock`. +Note that individual URI components are application specific and depend +on the underlying transport protocol. + +If this is a TCP/IP based connection and you only want the remote IP, you may +use something like this: + +```php +$address = $connection->getRemoteAddress(); +$ip = trim(parse_url($address, PHP_URL_HOST), '[]'); +echo 'Connection with ' . $ip . PHP_EOL; +``` + +#### getLocalAddress() + +The `getLocalAddress(): ?string` method returns the full local address +(URI) where this connection has been established with. + +```php +$address = $connection->getLocalAddress(); +echo 'Connection with ' . $address . PHP_EOL; +``` + +If the local address can not be determined or is unknown at this time (such as +after the connection has been closed), it MAY return a `NULL` value instead. + +Otherwise, it will return the full address (URI) as a string value, such +as `tcp://127.0.0.1:8080`, `tcp://[::1]:80`, `tls://127.0.0.1:443`, +`unix://example.sock` or `unix:///path/to/example.sock`. +Note that individual URI components are application specific and depend +on the underlying transport protocol. + +This method complements the [`getRemoteAddress()`](#getremoteaddress) method, +so they should not be confused. + +If your `TcpServer` instance is listening on multiple interfaces (e.g. using +the address `0.0.0.0`), you can use this method to find out which interface +actually accepted this connection (such as a public or local interface). + +If your system has multiple interfaces (e.g. a WAN and a LAN interface), +you can use this method to find out which interface was actually +used for this connection. + +## Server usage + +### ServerInterface + +The `ServerInterface` is responsible for providing an interface for accepting +incoming streaming connections, such as a normal TCP/IP connection. + +Most higher-level components (such as a HTTP server) accept an instance +implementing this interface to accept incoming streaming connections. +This is usually done via dependency injection, so it's fairly simple to actually +swap this implementation against any other implementation of this interface. +This means that you SHOULD typehint against this interface instead of a concrete +implementation of this interface. + +Besides defining a few methods, this interface also implements the +[`EventEmitterInterface`](https://github.com/igorw/evenement) +which allows you to react to certain events. + +#### connection event + +The `connection` event will be emitted whenever a new connection has been +established, i.e. a new client connects to this server socket: + +```php +$server->on('connection', function (ConnectionInterface $connection) { + echo 'new connection' . PHP_EOL; +}); +``` + +See also the [`ConnectionInterface`](#connectioninterface) for more details +about handling the incoming connection. + +#### error event + +The `error` event will be emitted whenever there's an error accepting a new +connection from a client. + +```php +$server->on('error', function (Exception $e) { + echo 'error: ' . $e->getMessage() . PHP_EOL; +}); +``` + +Note that this is not a fatal error event, i.e. the server keeps listening for +new connections even after this event. + + +#### getAddress() + +The `getAddress(): ?string` method can be used to +return the full address (URI) this server is currently listening on. + +```php +$address = $server->getAddress(); +echo 'Server listening on ' . $address . PHP_EOL; +``` + +If the address can not be determined or is unknown at this time (such as +after the socket has been closed), it MAY return a `NULL` value instead. + +Otherwise, it will return the full address (URI) as a string value, such +as `tcp://127.0.0.1:8080`, `tcp://[::1]:80`, `tls://127.0.0.1:443` +`unix://example.sock` or `unix:///path/to/example.sock`. +Note that individual URI components are application specific and depend +on the underlying transport protocol. + +If this is a TCP/IP based server and you only want the local port, you may +use something like this: + +```php +$address = $server->getAddress(); +$port = parse_url($address, PHP_URL_PORT); +echo 'Server listening on port ' . $port . PHP_EOL; +``` + +#### pause() + +The `pause(): void` method can be used to +pause accepting new incoming connections. + +Removes the socket resource from the EventLoop and thus stop accepting +new connections. Note that the listening socket stays active and is not +closed. + +This means that new incoming connections will stay pending in the +operating system backlog until its configurable backlog is filled. +Once the backlog is filled, the operating system may reject further +incoming connections until the backlog is drained again by resuming +to accept new connections. + +Once the server is paused, no futher `connection` events SHOULD +be emitted. + +```php +$server->pause(); + +$server->on('connection', assertShouldNeverCalled()); +``` + +This method is advisory-only, though generally not recommended, the +server MAY continue emitting `connection` events. + +Unless otherwise noted, a successfully opened server SHOULD NOT start +in paused state. + +You can continue processing events by calling `resume()` again. + +Note that both methods can be called any number of times, in particular +calling `pause()` more than once SHOULD NOT have any effect. +Similarly, calling this after `close()` is a NO-OP. + +#### resume() + +The `resume(): void` method can be used to +resume accepting new incoming connections. + +Re-attach the socket resource to the EventLoop after a previous `pause()`. + +```php +$server->pause(); + +$loop->addTimer(1.0, function () use ($server) { + $server->resume(); +}); +``` + +Note that both methods can be called any number of times, in particular +calling `resume()` without a prior `pause()` SHOULD NOT have any effect. +Similarly, calling this after `close()` is a NO-OP. + +#### close() + +The `close(): void` method can be used to +shut down this listening socket. + +This will stop listening for new incoming connections on this socket. + +```php +echo 'Shutting down server socket' . PHP_EOL; +$server->close(); +``` + +Calling this method more than once on the same instance is a NO-OP. + +### Server + +The `Server` class is the main class in this package that implements the +[`ServerInterface`](#serverinterface) and allows you to accept incoming +streaming connections, such as plaintext TCP/IP or secure TLS connection streams. +Connections can also be accepted on Unix domain sockets. + +```php +$server = new Server(8080, $loop); +``` + +As above, the `$uri` parameter can consist of only a port, in which case the +server will default to listening on the localhost address `127.0.0.1`, +which means it will not be reachable from outside of this system. + +In order to use a random port assignment, you can use the port `0`: + +```php +$server = new Server(0, $loop); +$address = $server->getAddress(); +``` + +In order to change the host the socket is listening on, you can provide an IP +address through the first parameter provided to the constructor, optionally +preceded by the `tcp://` scheme: + +```php +$server = new Server('192.168.0.1:8080', $loop); +``` + +If you want to listen on an IPv6 address, you MUST enclose the host in square +brackets: + +```php +$server = new Server('[::1]:8080', $loop); +``` + +To listen on a Unix domain socket (UDS) path, you MUST prefix the URI with the +`unix://` scheme: + +```php +$server = new Server('unix:///tmp/server.sock', $loop); +``` + +If the given URI is invalid, does not contain a port, any other scheme or if it +contains a hostname, it will throw an `InvalidArgumentException`: + +```php +// throws InvalidArgumentException due to missing port +$server = new Server('127.0.0.1', $loop); +``` + +If the given URI appears to be valid, but listening on it fails (such as if port +is already in use or port below 1024 may require root access etc.), it will +throw a `RuntimeException`: + +```php +$first = new Server(8080, $loop); + +// throws RuntimeException because port is already in use +$second = new Server(8080, $loop); +``` + +> Note that these error conditions may vary depending on your system and/or + configuration. + See the exception message and code for more details about the actual error + condition. + +Optionally, you can specify [TCP socket context options](http://php.net/manual/en/context.socket.php) +for the underlying stream socket resource like this: + +```php +$server = new Server('[::1]:8080', $loop, array( + 'tcp' => array( + 'backlog' => 200, + 'so_reuseport' => true, + 'ipv6_v6only' => true + ) +)); +``` + +> Note that available [socket context options](http://php.net/manual/en/context.socket.php), + their defaults and effects of changing these may vary depending on your system + and/or PHP version. + Passing unknown context options has no effect. + For BC reasons, you can also pass the TCP socket context options as a simple + array without wrapping this in another array under the `tcp` key. + +You can start a secure TLS (formerly known as SSL) server by simply prepending +the `tls://` URI scheme. +Internally, it will wait for plaintext TCP/IP connections and then performs a +TLS handshake for each connection. +It thus requires valid [TLS context options](http://php.net/manual/en/context.ssl.php), +which in its most basic form may look something like this if you're using a +PEM encoded certificate file: + +```php +$server = new Server('tls://127.0.0.1:8080', $loop, array( + 'tls' => array( + 'local_cert' => 'server.pem' + ) +)); +``` + +> Note that the certificate file will not be loaded on instantiation but when an + incoming connection initializes its TLS context. + This implies that any invalid certificate file paths or contents will only cause + an `error` event at a later time. + +If your private key is encrypted with a passphrase, you have to specify it +like this: + +```php +$server = new Server('tls://127.0.0.1:8000', $loop, array( + 'tls' => array( + 'local_cert' => 'server.pem', + 'passphrase' => 'secret' + ) +)); +``` + +By default, this server supports TLSv1.0+ and excludes support for legacy +SSLv2/SSLv3. As of PHP 5.6+ you can also explicitly choose the TLS version you +want to negotiate with the remote side: + +```php +$server = new Server('tls://127.0.0.1:8000', $loop, array( + 'tls' => array( + 'local_cert' => 'server.pem', + 'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_SERVER + ) +)); +``` + +> Note that available [TLS context options](http://php.net/manual/en/context.ssl.php), + their defaults and effects of changing these may vary depending on your system + and/or PHP version. + The outer context array allows you to also use `tcp` (and possibly more) + context options at the same time. + Passing unknown context options has no effect. + If you do not use the `tls://` scheme, then passing `tls` context options + has no effect. + +Whenever a client connects, it will emit a `connection` event with a connection +instance implementing [`ConnectionInterface`](#connectioninterface): + +```php +$server->on('connection', function (ConnectionInterface $connection) { + echo 'Plaintext connection from ' . $connection->getRemoteAddress() . PHP_EOL; + + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +See also the [`ServerInterface`](#serverinterface) for more details. + +> Note that the `Server` class is a concrete implementation for TCP/IP sockets. + If you want to typehint in your higher-level protocol implementation, you SHOULD + use the generic [`ServerInterface`](#serverinterface) instead. + +### Advanced server usage + +#### TcpServer + +The `TcpServer` class implements the [`ServerInterface`](#serverinterface) and +is responsible for accepting plaintext TCP/IP connections. + +```php +$server = new TcpServer(8080, $loop); +``` + +As above, the `$uri` parameter can consist of only a port, in which case the +server will default to listening on the localhost address `127.0.0.1`, +which means it will not be reachable from outside of this system. + +In order to use a random port assignment, you can use the port `0`: + +```php +$server = new TcpServer(0, $loop); +$address = $server->getAddress(); +``` + +In order to change the host the socket is listening on, you can provide an IP +address through the first parameter provided to the constructor, optionally +preceded by the `tcp://` scheme: + +```php +$server = new TcpServer('192.168.0.1:8080', $loop); +``` + +If you want to listen on an IPv6 address, you MUST enclose the host in square +brackets: + +```php +$server = new TcpServer('[::1]:8080', $loop); +``` + +If the given URI is invalid, does not contain a port, any other scheme or if it +contains a hostname, it will throw an `InvalidArgumentException`: + +```php +// throws InvalidArgumentException due to missing port +$server = new TcpServer('127.0.0.1', $loop); +``` + +If the given URI appears to be valid, but listening on it fails (such as if port +is already in use or port below 1024 may require root access etc.), it will +throw a `RuntimeException`: + +```php +$first = new TcpServer(8080, $loop); + +// throws RuntimeException because port is already in use +$second = new TcpServer(8080, $loop); +``` + +> Note that these error conditions may vary depending on your system and/or +configuration. +See the exception message and code for more details about the actual error +condition. + +Optionally, you can specify [socket context options](http://php.net/manual/en/context.socket.php) +for the underlying stream socket resource like this: + +```php +$server = new TcpServer('[::1]:8080', $loop, array( + 'backlog' => 200, + 'so_reuseport' => true, + 'ipv6_v6only' => true +)); +``` + +> Note that available [socket context options](http://php.net/manual/en/context.socket.php), +their defaults and effects of changing these may vary depending on your system +and/or PHP version. +Passing unknown context options has no effect. + +Whenever a client connects, it will emit a `connection` event with a connection +instance implementing [`ConnectionInterface`](#connectioninterface): + +```php +$server->on('connection', function (ConnectionInterface $connection) { + echo 'Plaintext connection from ' . $connection->getRemoteAddress() . PHP_EOL; + + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +See also the [`ServerInterface`](#serverinterface) for more details. + +#### SecureServer + +The `SecureServer` class implements the [`ServerInterface`](#serverinterface) +and is responsible for providing a secure TLS (formerly known as SSL) server. + +It does so by wrapping a [`TcpServer`](#tcpserver) instance which waits for plaintext +TCP/IP connections and then performs a TLS handshake for each connection. +It thus requires valid [TLS context options](http://php.net/manual/en/context.ssl.php), +which in its most basic form may look something like this if you're using a +PEM encoded certificate file: + +```php +$server = new TcpServer(8000, $loop); +$server = new SecureServer($server, $loop, array( + 'local_cert' => 'server.pem' +)); +``` + +> Note that the certificate file will not be loaded on instantiation but when an +incoming connection initializes its TLS context. +This implies that any invalid certificate file paths or contents will only cause +an `error` event at a later time. + +If your private key is encrypted with a passphrase, you have to specify it +like this: + +```php +$server = new TcpServer(8000, $loop); +$server = new SecureServer($server, $loop, array( + 'local_cert' => 'server.pem', + 'passphrase' => 'secret' +)); +``` + +By default, this server supports TLSv1.0+ and excludes support for legacy +SSLv2/SSLv3. As of PHP 5.6+ you can also explicitly choose the TLS version you +want to negotiate with the remote side: + +```php +$server = new TcpServer(8000, $loop); +$server = new SecureServer($server, $loop, array( + 'local_cert' => 'server.pem', + 'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_SERVER +)); +``` + +> Note that available [TLS context options](http://php.net/manual/en/context.ssl.php), +their defaults and effects of changing these may vary depending on your system +and/or PHP version. +Passing unknown context options has no effect. + +Whenever a client completes the TLS handshake, it will emit a `connection` event +with a connection instance implementing [`ConnectionInterface`](#connectioninterface): + +```php +$server->on('connection', function (ConnectionInterface $connection) { + echo 'Secure connection from' . $connection->getRemoteAddress() . PHP_EOL; + + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +Whenever a client fails to perform a successful TLS handshake, it will emit an +`error` event and then close the underlying TCP/IP connection: + +```php +$server->on('error', function (Exception $e) { + echo 'Error' . $e->getMessage() . PHP_EOL; +}); +``` + +See also the [`ServerInterface`](#serverinterface) for more details. + +Note that the `SecureServer` class is a concrete implementation for TLS sockets. +If you want to typehint in your higher-level protocol implementation, you SHOULD +use the generic [`ServerInterface`](#serverinterface) instead. + +> Advanced usage: Despite allowing any `ServerInterface` as first parameter, +you SHOULD pass a `TcpServer` instance as first parameter, unless you +know what you're doing. +Internally, the `SecureServer` has to set the required TLS context options on +the underlying stream resources. +These resources are not exposed through any of the interfaces defined in this +package, but only through the internal `Connection` class. +The `TcpServer` class is guaranteed to emit connections that implement +the `ConnectionInterface` and uses the internal `Connection` class in order to +expose these underlying resources. +If you use a custom `ServerInterface` and its `connection` event does not +meet this requirement, the `SecureServer` will emit an `error` event and +then close the underlying connection. + +#### UnixServer + +The `UnixServer` class implements the [`ServerInterface`](#serverinterface) and +is responsible for accepting connections on Unix domain sockets (UDS). + +```php +$server = new UnixServer('/tmp/server.sock', $loop); +``` + +As above, the `$uri` parameter can consist of only a socket path or socket path +prefixed by the `unix://` scheme. + +If the given URI appears to be valid, but listening on it fails (such as if the +socket is already in use or the file not accessible etc.), it will throw a +`RuntimeException`: + +```php +$first = new UnixServer('/tmp/same.sock', $loop); + +// throws RuntimeException because socket is already in use +$second = new UnixServer('/tmp/same.sock', $loop); +``` + +Whenever a client connects, it will emit a `connection` event with a connection +instance implementing [`ConnectionInterface`](#connectioninterface): + +```php +$server->on('connection', function (ConnectionInterface $connection) { + echo 'New connection' . PHP_EOL; + + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +See also the [`ServerInterface`](#serverinterface) for more details. + +#### LimitingServer + +The `LimitingServer` decorator wraps a given `ServerInterface` and is responsible +for limiting and keeping track of open connections to this server instance. + +Whenever the underlying server emits a `connection` event, it will check its +limits and then either + - keep track of this connection by adding it to the list of + open connections and then forward the `connection` event + - or reject (close) the connection when its limits are exceeded and will + forward an `error` event instead. + +Whenever a connection closes, it will remove this connection from the list of +open connections. + +```php +$server = new LimitingServer($server, 100); +$server->on('connection', function (ConnectionInterface $connection) { + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +See also the [second example](examples) for more details. + +You have to pass a maximum number of open connections to ensure +the server will automatically reject (close) connections once this limit +is exceeded. In this case, it will emit an `error` event to inform about +this and no `connection` event will be emitted. + +```php +$server = new LimitingServer($server, 100); +$server->on('connection', function (ConnectionInterface $connection) { + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +You MAY pass a `null` limit in order to put no limit on the number of +open connections and keep accepting new connection until you run out of +operating system resources (such as open file handles). This may be +useful if you do not want to take care of applying a limit but still want +to use the `getConnections()` method. + +You can optionally configure the server to pause accepting new +connections once the connection limit is reached. In this case, it will +pause the underlying server and no longer process any new connections at +all, thus also no longer closing any excessive connections. +The underlying operating system is responsible for keeping a backlog of +pending connections until its limit is reached, at which point it will +start rejecting further connections. +Once the server is below the connection limit, it will continue consuming +connections from the backlog and will process any outstanding data on +each connection. +This mode may be useful for some protocols that are designed to wait for +a response message (such as HTTP), but may be less useful for other +protocols that demand immediate responses (such as a "welcome" message in +an interactive chat). + +```php +$server = new LimitingServer($server, 100, true); +$server->on('connection', function (ConnectionInterface $connection) { + $connection->write('hello there!' . PHP_EOL); + … +}); +``` + +##### getConnections() + +The `getConnections(): ConnectionInterface[]` method can be used to +return an array with all currently active connections. + +```php +foreach ($server->getConnection() as $connection) { + $connection->write('Hi!'); +} +``` + +## Client usage + +### ConnectorInterface + +The `ConnectorInterface` is responsible for providing an interface for +establishing streaming connections, such as a normal TCP/IP connection. + +This is the main interface defined in this package and it is used throughout +React's vast ecosystem. + +Most higher-level components (such as HTTP, database or other networking +service clients) accept an instance implementing this interface to create their +TCP/IP connection to the underlying networking service. +This is usually done via dependency injection, so it's fairly simple to actually +swap this implementation against any other implementation of this interface. + +The interface only offers a single method: + +#### connect() + +The `connect(string $uri): PromiseInterface<ConnectionInterface, Exception>` method +can be used to create a streaming connection to the given remote address. + +It returns a [Promise](https://github.com/reactphp/promise) which either +fulfills with a stream implementing [`ConnectionInterface`](#connectioninterface) +on success or rejects with an `Exception` if the connection is not successful: + +```php +$connector->connect('google.com:443')->then( + function (ConnectionInterface $connection) { + // connection successfully established + }, + function (Exception $error) { + // failed to connect due to $error + } +); +``` + +See also [`ConnectionInterface`](#connectioninterface) for more details. + +The returned Promise MUST be implemented in such a way that it can be +cancelled when it is still pending. Cancelling a pending promise MUST +reject its value with an `Exception`. It SHOULD clean up any underlying +resources and references as applicable: + +```php +$promise = $connector->connect($uri); + +$promise->cancel(); +``` + +### Connector + +The `Connector` class is the main class in this package that implements the +[`ConnectorInterface`](#connectorinterface) and allows you to create streaming connections. + +You can use this connector to create any kind of streaming connections, such +as plaintext TCP/IP, secure TLS or local Unix connection streams. + +It binds to the main event loop and can be used like this: + +```php +$loop = React\EventLoop\Factory::create(); +$connector = new Connector($loop); + +$connector->connect($uri)->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); + +$loop->run(); +``` + +In order to create a plaintext TCP/IP connection, you can simply pass a host +and port combination like this: + +```php +$connector->connect('www.google.com:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +> If you do no specify a URI scheme in the destination URI, it will assume + `tcp://` as a default and establish a plaintext TCP/IP connection. + Note that TCP/IP connections require a host and port part in the destination + URI like above, all other URI components are optional. + +In order to create a secure TLS connection, you can use the `tls://` URI scheme +like this: + +```php +$connector->connect('tls://www.google.com:443')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +In order to create a local Unix domain socket connection, you can use the +`unix://` URI scheme like this: + +```php +$connector->connect('unix:///tmp/demo.sock')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +> The [`getRemoteAddress()`](#getremoteaddress) method will return the target + Unix domain socket (UDS) path as given to the `connect()` method, including + the `unix://` scheme, for example `unix:///tmp/demo.sock`. + The [`getLocalAddress()`](#getlocaladdress) method will most likely return a + `null` value as this value is not applicable to UDS connections here. + +Under the hood, the `Connector` is implemented as a *higher-level facade* +for the lower-level connectors implemented in this package. This means it +also shares all of their features and implementation details. +If you want to typehint in your higher-level protocol implementation, you SHOULD +use the generic [`ConnectorInterface`](#connectorinterface) instead. + +The `Connector` class will try to detect your system DNS settings (and uses +Google's public DNS server `8.8.8.8` as a fallback if unable to determine your +system settings) to resolve all public hostnames into underlying IP addresses by +default. +If you explicitly want to use a custom DNS server (such as a local DNS relay or +a company wide DNS server), you can set up the `Connector` like this: + +```php +$connector = new Connector($loop, array( + 'dns' => '127.0.1.1' +)); + +$connector->connect('localhost:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +If you do not want to use a DNS resolver at all and want to connect to IP +addresses only, you can also set up your `Connector` like this: + +```php +$connector = new Connector($loop, array( + 'dns' => false +)); + +$connector->connect('127.0.0.1:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +Advanced: If you need a custom DNS `Resolver` instance, you can also set up +your `Connector` like this: + +```php +$dnsResolverFactory = new React\Dns\Resolver\Factory(); +$resolver = $dnsResolverFactory->createCached('127.0.1.1', $loop); + +$connector = new Connector($loop, array( + 'dns' => $resolver +)); + +$connector->connect('localhost:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +By default, the `tcp://` and `tls://` URI schemes will use timeout value that +repects your `default_socket_timeout` ini setting (which defaults to 60s). +If you want a custom timeout value, you can simply pass this like this: + +```php +$connector = new Connector($loop, array( + 'timeout' => 10.0 +)); +``` + +Similarly, if you do not want to apply a timeout at all and let the operating +system handle this, you can pass a boolean flag like this: + +```php +$connector = new Connector($loop, array( + 'timeout' => false +)); +``` + +By default, the `Connector` supports the `tcp://`, `tls://` and `unix://` +URI schemes. If you want to explicitly prohibit any of these, you can simply +pass boolean flags like this: + +```php +// only allow secure TLS connections +$connector = new Connector($loop, array( + 'tcp' => false, + 'tls' => true, + 'unix' => false, +)); + +$connector->connect('tls://google.com:443')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +The `tcp://` and `tls://` also accept additional context options passed to +the underlying connectors. +If you want to explicitly pass additional context options, you can simply +pass arrays of context options like this: + +```php +// allow insecure TLS connections +$connector = new Connector($loop, array( + 'tcp' => array( + 'bindto' => '192.168.0.1:0' + ), + 'tls' => array( + 'verify_peer' => false, + 'verify_peer_name' => false + ), +)); + +$connector->connect('tls://localhost:443')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +By default, this connector supports TLSv1.0+ and excludes support for legacy +SSLv2/SSLv3. As of PHP 5.6+ you can also explicitly choose the TLS version you +want to negotiate with the remote side: + +```php +$connector = new Connector($loop, array( + 'tls' => array( + 'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT + ) +)); +``` + +> For more details about context options, please refer to the PHP documentation + about [socket context options](http://php.net/manual/en/context.socket.php) + and [SSL context options](http://php.net/manual/en/context.ssl.php). + +Advanced: By default, the `Connector` supports the `tcp://`, `tls://` and +`unix://` URI schemes. +For this, it sets up the required connector classes automatically. +If you want to explicitly pass custom connectors for any of these, you can simply +pass an instance implementing the `ConnectorInterface` like this: + +```php +$dnsResolverFactory = new React\Dns\Resolver\Factory(); +$resolver = $dnsResolverFactory->createCached('127.0.1.1', $loop); +$tcp = new DnsConnector(new TcpConnector($loop), $resolver); + +$tls = new SecureConnector($tcp, $loop); + +$unix = new UnixConnector($loop); + +$connector = new Connector($loop, array( + 'tcp' => $tcp, + 'tls' => $tls, + 'unix' => $unix, + + 'dns' => false, + 'timeout' => false, +)); + +$connector->connect('google.com:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); +``` + +> Internally, the `tcp://` connector will always be wrapped by the DNS resolver, + unless you disable DNS like in the above example. In this case, the `tcp://` + connector receives the actual hostname instead of only the resolved IP address + and is thus responsible for performing the lookup. + Internally, the automatically created `tls://` connector will always wrap the + underlying `tcp://` connector for establishing the underlying plaintext + TCP/IP connection before enabling secure TLS mode. If you want to use a custom + underlying `tcp://` connector for secure TLS connections only, you may + explicitly pass a `tls://` connector like above instead. + Internally, the `tcp://` and `tls://` connectors will always be wrapped by + `TimeoutConnector`, unless you disable timeouts like in the above example. + +### Advanced client usage + +#### TcpConnector + +The `React\Socket\TcpConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and allows you to create plaintext +TCP/IP connections to any IP-port-combination: + +```php +$tcpConnector = new React\Socket\TcpConnector($loop); + +$tcpConnector->connect('127.0.0.1:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); + +$loop->run(); +``` + +See also the [examples](examples). + +Pending connection attempts can be cancelled by cancelling its pending promise like so: + +```php +$promise = $tcpConnector->connect('127.0.0.1:80'); + +$promise->cancel(); +``` + +Calling `cancel()` on a pending promise will close the underlying socket +resource, thus cancelling the pending TCP/IP connection, and reject the +resulting promise. + +You can optionally pass additional +[socket context options](http://php.net/manual/en/context.socket.php) +to the constructor like this: + +```php +$tcpConnector = new React\Socket\TcpConnector($loop, array( + 'bindto' => '192.168.0.1:0' +)); +``` + +Note that this class only allows you to connect to IP-port-combinations. +If the given URI is invalid, does not contain a valid IP address and port +or contains any other scheme, it will reject with an +`InvalidArgumentException`: + +If the given URI appears to be valid, but connecting to it fails (such as if +the remote host rejects the connection etc.), it will reject with a +`RuntimeException`. + +If you want to connect to hostname-port-combinations, see also the following chapter. + +> Advanced usage: Internally, the `TcpConnector` allocates an empty *context* +resource for each stream resource. +If the destination URI contains a `hostname` query parameter, its value will +be used to set up the TLS peer name. +This is used by the `SecureConnector` and `DnsConnector` to verify the peer +name and can also be used if you want a custom TLS peer name. + +#### DnsConnector + +The `DnsConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and allows you to create plaintext +TCP/IP connections to any hostname-port-combination. + +It does so by decorating a given `TcpConnector` instance so that it first +looks up the given domain name via DNS (if applicable) and then establishes the +underlying TCP/IP connection to the resolved target IP address. + +Make sure to set up your DNS resolver and underlying TCP connector like this: + +```php +$dnsResolverFactory = new React\Dns\Resolver\Factory(); +$dns = $dnsResolverFactory->createCached('8.8.8.8', $loop); + +$dnsConnector = new React\Socket\DnsConnector($tcpConnector, $dns); + +$dnsConnector->connect('www.google.com:80')->then(function (ConnectionInterface $connection) { + $connection->write('...'); + $connection->end(); +}); + +$loop->run(); +``` + +See also the [examples](examples). + +Pending connection attempts can be cancelled by cancelling its pending promise like so: + +```php +$promise = $dnsConnector->connect('www.google.com:80'); + +$promise->cancel(); +``` + +Calling `cancel()` on a pending promise will cancel the underlying DNS lookup +and/or the underlying TCP/IP connection and reject the resulting promise. + +> Advanced usage: Internally, the `DnsConnector` relies on a `Resolver` to +look up the IP address for the given hostname. +It will then replace the hostname in the destination URI with this IP and +append a `hostname` query parameter and pass this updated URI to the underlying +connector. +The underlying connector is thus responsible for creating a connection to the +target IP address, while this query parameter can be used to check the original +hostname and is used by the `TcpConnector` to set up the TLS peer name. +If a `hostname` is given explicitly, this query parameter will not be modified, +which can be useful if you want a custom TLS peer name. + +#### SecureConnector + +The `SecureConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and allows you to create secure +TLS (formerly known as SSL) connections to any hostname-port-combination. + +It does so by decorating a given `DnsConnector` instance so that it first +creates a plaintext TCP/IP connection and then enables TLS encryption on this +stream. + +```php +$secureConnector = new React\Socket\SecureConnector($dnsConnector, $loop); + +$secureConnector->connect('www.google.com:443')->then(function (ConnectionInterface $connection) { + $connection->write("GET / HTTP/1.0\r\nHost: www.google.com\r\n\r\n"); + ... +}); + +$loop->run(); +``` + +See also the [examples](examples). + +Pending connection attempts can be cancelled by cancelling its pending promise like so: + +```php +$promise = $secureConnector->connect('www.google.com:443'); + +$promise->cancel(); +``` + +Calling `cancel()` on a pending promise will cancel the underlying TCP/IP +connection and/or the SSL/TLS negotiation and reject the resulting promise. + +You can optionally pass additional +[SSL context options](http://php.net/manual/en/context.ssl.php) +to the constructor like this: + +```php +$secureConnector = new React\Socket\SecureConnector($dnsConnector, $loop, array( + 'verify_peer' => false, + 'verify_peer_name' => false +)); +``` + +By default, this connector supports TLSv1.0+ and excludes support for legacy +SSLv2/SSLv3. As of PHP 5.6+ you can also explicitly choose the TLS version you +want to negotiate with the remote side: + +```php +$secureConnector = new React\Socket\SecureConnector($dnsConnector, $loop, array( + 'crypto_method' => STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT +)); +``` + +> Advanced usage: Internally, the `SecureConnector` relies on setting up the +required *context options* on the underlying stream resource. +It should therefor be used with a `TcpConnector` somewhere in the connector +stack so that it can allocate an empty *context* resource for each stream +resource and verify the peer name. +Failing to do so may result in a TLS peer name mismatch error or some hard to +trace race conditions, because all stream resources will use a single, shared +*default context* resource otherwise. + +#### TimeoutConnector + +The `TimeoutConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and allows you to add timeout +handling to any existing connector instance. + +It does so by decorating any given [`ConnectorInterface`](#connectorinterface) +instance and starting a timer that will automatically reject and abort any +underlying connection attempt if it takes too long. + +```php +$timeoutConnector = new React\Socket\TimeoutConnector($connector, 3.0, $loop); + +$timeoutConnector->connect('google.com:80')->then(function (ConnectionInterface $connection) { + // connection succeeded within 3.0 seconds +}); +``` + +See also any of the [examples](examples). + +Pending connection attempts can be cancelled by cancelling its pending promise like so: + +```php +$promise = $timeoutConnector->connect('google.com:80'); + +$promise->cancel(); +``` + +Calling `cancel()` on a pending promise will cancel the underlying connection +attempt, abort the timer and reject the resulting promise. + +#### UnixConnector + +The `UnixConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and allows you to connect to +Unix domain socket (UDS) paths like this: + +```php +$connector = new React\Socket\UnixConnector($loop); + +$connector->connect('/tmp/demo.sock')->then(function (ConnectionInterface $connection) { + $connection->write("HELLO\n"); +}); + +$loop->run(); +``` + +Connecting to Unix domain sockets is an atomic operation, i.e. its promise will +settle (either resolve or reject) immediately. +As such, calling `cancel()` on the resulting promise has no effect. + +> The [`getRemoteAddress()`](#getremoteaddress) method will return the target + Unix domain socket (UDS) path as given to the `connect()` method, prepended + with the `unix://` scheme, for example `unix:///tmp/demo.sock`. + The [`getLocalAddress()`](#getlocaladdress) method will most likely return a + `null` value as this value is not applicable to UDS connections here. + +#### FixedUriConnector + +The `FixedUriConnector` class implements the +[`ConnectorInterface`](#connectorinterface) and decorates an existing Connector +to always use a fixed, preconfigured URI. + +This can be useful for consumers that do not support certain URIs, such as +when you want to explicitly connect to a Unix domain socket (UDS) path +instead of connecting to a default address assumed by an higher-level API: + +```php +$connector = new FixedUriConnector( + 'unix:///var/run/docker.sock', + new UnixConnector($loop) +); + +// destination will be ignored, actually connects to Unix domain socket +$promise = $connector->connect('localhost:80'); +``` + +## Install + +The recommended way to install this library is [through Composer](https://getcomposer.org). +[New to Composer?](https://getcomposer.org/doc/00-intro.md) + +This will install the latest supported version: + +```bash +$ composer require react/socket:^0.8.10 +``` + +See also the [CHANGELOG](CHANGELOG.md) for details about version upgrades. + +This project aims to run on any platform and thus does not require any PHP +extensions and supports running on legacy PHP 5.3 through current PHP 7+ and HHVM. +It's *highly recommended to use PHP 7+* for this project, partly due to its vast +performance improvements and partly because legacy PHP versions require several +workarounds as described below. + +Secure TLS connections received some major upgrades starting with PHP 5.6, with +the defaults now being more secure, while older versions required explicit +context options. +This library does not take responsibility over these context options, so it's +up to consumers of this library to take care of setting appropriate context +options as described above. + +All versions of PHP prior to 5.6.8 suffered from a buffering issue where reading +from a streaming TLS connection could be one `data` event behind. +This library implements a work-around to try to flush the complete incoming +data buffers on these legacy PHP versions, which has a penalty of around 10% of +throughput on all connections. +With this work-around, we have not been able to reproduce this issue anymore, +but we have seen reports of people saying this could still affect some of the +older PHP versions (`5.5.23`, `5.6.7`, and `5.6.8`). +Note that this only affects *some* higher-level streaming protocols, such as +IRC over TLS, but should not affect HTTP over TLS (HTTPS). +Further investigation of this issue is needed. +For more insights, this issue is also covered by our test suite. + +PHP < 7.1.4 (and PHP < 7.0.18) suffers from a bug when writing big +chunks of data over TLS streams at once. +We try to work around this by limiting the write chunk size to 8192 +bytes for older PHP versions only. +This is only a work-around and has a noticable performance penalty on +affected versions. + +This project also supports running on HHVM. +Note that really old HHVM < 3.8 does not support secure TLS connections, as it +lacks the required `stream_socket_enable_crypto()` function. +As such, trying to create a secure TLS connections on affected versions will +return a rejected promise instead. +This issue is also covered by our test suite, which will skip related tests +on affected versions. + +## Tests + +To run the test suite, you first need to clone this repo and then install all +dependencies [through Composer](https://getcomposer.org): + +```bash +$ composer install +``` + +To run the test suite, go to the project root and run: + +```bash +$ php vendor/bin/phpunit +``` + +The test suite also contains a number of functional integration tests that rely +on a stable internet connection. +If you do not want to run these, they can simply be skipped like this: + +```bash +$ php vendor/bin/phpunit --exclude-group internet +``` + +## License + +MIT, see [LICENSE file](LICENSE). |