Documentation

This method can be used to (forcefully) close the stream.

$stream->close();

Once the stream is closed, it SHOULD emit a close event. Note that this event SHOULD NOT be emitted more than once, in particular if this method is called multiple times.

After calling this method, the stream MUST switch into a non-readable mode, see also isReadable(). This means that no further data or end events SHOULD be emitted.

$stream->close();
assert($stream->isReadable() === false);

$stream->on('data', assertNeverCalled());
$stream->on('end', assertNeverCalled());

If this stream is a DuplexStreamInterface, you should also notice how the writable side of the stream also implements a close() method. In other words, after calling this method, the stream MUST switch into non-writable AND non-readable mode, see also isWritable(). Note that this method should not be confused with the end() method.

This method can be used to check if the stream still accepts incoming data events or if it is ended or closed already. Once the stream is non-readable, no further data or end events SHOULD be emitted.

assert($stream->isReadable() === false);

$stream->on('data', assertNeverCalled());
$stream->on('end', assertNeverCalled());

A successfully opened stream always MUST start in readable mode.

Once the stream ends or closes, it MUST switch to non-readable mode. This can happen any time, explicitly through close() or implicitly due to a remote close or an unrecoverable transmission error. Once a stream has switched to non-readable mode, it MUST NOT transition back to readable mode.

If this stream is a DuplexStreamInterface, you should also notice how the writable side of the stream also implements an isWritable() method. Unless this is a half-open duplex stream, they SHOULD usually have the same return value.

Removes the data source file descriptor from the event loop. This allows you to throttle incoming data.

Unless otherwise noted, a successfully opened stream SHOULD NOT start in paused state.

Once the stream is paused, no futher data or end events SHOULD be emitted.

$stream->pause();

$stream->on('data', assertShouldNeverCalled());
$stream->on('end', assertShouldNeverCalled());

This method is advisory-only, though generally not recommended, the stream MAY continue emitting data events.

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.

Automatically sends all incoming data to the destination. Automatically throttles the source based on what the destination can handle.

$source->pipe($dest);

Similarly, you can also pipe an instance implementing DuplexStreamInterface into itself in order to write back all the data that is received. This may be a useful feature for a TCP/IP echo service:

$connection->pipe($connection);

This method returns the destination stream as-is, which can be used to set up chains of piped streams:

$source->pipe($decodeGzip)->pipe($filterBadWords)->pipe($dest);

By default, this will call end() on the destination stream once the source stream emits an end event. This can be disabled like this:

$source->pipe($dest, array('end' => false));

Note that this only applies to the end event. If an error or explicit close event happens on the source stream, you'll have to manually close the destination stream:

$source->pipe($dest);
$source->on('close', function () use ($dest) {
    $dest->end('BYE!');
});

If the source stream is not readable (closed state), then this is a NO-OP.

$source->close();
$source->pipe($dest); // NO-OP

If the destinantion stream is not writable (closed state), then this will simply throttle (pause) the source stream:

$dest->close();
$source->pipe($dest); // calls $source->pause()

Similarly, if the destination stream is closed while the pipe is still active, it will also throttle (pause) the source stream:

$source->pipe($dest);
$dest->close(); // calls $source->pause()

Once the pipe is set up successfully, the destination stream MUST emit a pipe event with this source stream an event argument.

Re-attach the data source after a previous pause().

$stream->pause();

Loop::addTimer(1.0, function () use ($stream) {
    $stream->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.