clue/term-react

Streaming terminal emulator, built on top of ReactPHP

Table of Contents

• Usage
  • ControlCodeParser
• Install
• Tests
• License
• More

Usage

ControlCodeParser

The ControlCodeParser(ReadableStreamInterface $input) class can be used to parse any control code byte sequences (ANSI / VT100) when reading from an input stream and it only returns its plain data stream. It wraps a given ReadableStreamInterface and exposes its plain data through the same interface.

$stdin = new ReadableResourceStream(STDIN, $loop);

$stream = new ControlCodeParser($stdin);

$stream->on('data', function ($chunk) {
    var_dump($chunk);
});

As such, you can be sure the resulting data events never include any control code byte sequences and it can be processed like a normal plain data stream.

React's streams emit chunks of data strings and make no assumption about any byte sequences. These chunks do not necessarily represent complete control code byte sequences, as a sequence may be broken up into multiple chunks. This class reassembles these sequences by buffering incomplete ones.

The following C1 control codes are supported as defined in ISO/IEC 2022:

• CSI (Control Sequence Introducer) is one of the most common forms of control code sequences. For example, CSI is used to print colored console output, also known as "ANSI color codes" or the more technical term SGR (Select Graphic Rendition). CSI codes also appear on STDIN, for example when the user hits special keys, such as the cursor, HOME, END etc. keys.

• OSC (Operating System Command) is another common form of control code sequences. For example, OSC is used to change the window title or window icon.

• APC (Application Program-Control)

• DPS (Device-Control string)

• PM (Privacy Message)

Each code sequence gets emitted with a dedicated event with its raw byte sequence:

$stream->on('csi', function ($sequence) {
    if ($sequence === "\x1B[A") {
        echo 'cursor UP pressed';
    } else if ($sequence === "\x1B[B") {
        echo 'cursor DOWN pressed';
    }
});

$stream->on('osc', function ($sequence) { … });
$stream->on('apc', function ($sequence) { … });
$stream->on('dps', function ($sequence) { … });
$stream->on('pm', function ($sequence) { … });

Other lesser known C1 control codes not listed above are supported by just emitting their 2-byte sequence. Each generic C1 code gets emitted as an c1 event with its raw 2-byte sequence:

$stream->on('c1', function ($sequence) { … });

All other C0 control codes, also known as ASCII control codes, are supported by just emitting their single-byte value. Each generic C0 code gets emitted as an c0 event with its raw single-byte value:

$stream->on('c0', function ($code) {
    if ($code === "\n") {
        echo 'ENTER pressed';
    }
});

Install

The recommended way to install this library is through Composer. New to Composer?

This will install the latest supported version:

$ composer require clue/term-react:^1.0

See also the CHANGELOG for details about version upgrades.

Tests

To run the test suite, you first need to clone this repo and then install all dependencies through Composer:

$ composer install

To run the test suite, go to the project root and run:

$ php vendor/bin/phpunit

License

MIT

More

• If you want to learn more about processing streams of data, refer to the documentation of the underlying react/stream component.

• If you want to process UTF-8 encoded console input, you may want to use clue/utf8-react on the resulting plain data stream.

• If you want to to display or inspect the control codes, you may want to use either clue/hexdump or clue/caret-notation on the emitted control byte sequences.

• If you want to process standard input and output (STDIN and STDOUT) from a TTY, you may want to use clue/stdio-react instead of using this low-level library.