Console adapters

zend-console's console abstraction layer works around various bugs and limitations in operating systems, including:

Console adapters implement Zend\Console\Adapter\AdapterInterface, and you should typehint against that interface for purposes of working with console capabilities. Adapters are included for:

Retrieving the console adapter

While you may know your current environment, you will want to write your code in such a way that the console adapter is specific to whatever environment it is run within. As such, you likely should never instantiate an adapter directly. zend-console, and the zend-mvc integration, provide tools for retrieving an appropriate adapter for the current environment in a generic way.

Standalone

zend-console provides a factory for creating and returning the console adapter specific to your environment:

use Zend\Console\Console;
use Zend\Console\Exception\ExceptionInterface as ConsoleException;

try {
    $console = Console::getInstance();
} catch (ConsoleException $e) {
    // Could not get console adapter; most likely we are not running inside a
    // console window.
}

This returns a Zend\Console\Adapter\AdapterInterface implementation suitable for your current environment.

Exceptions

For practical and security reasons, Console::getInstance() will always throw an exception if you attempt to get console instance in a non-console environment (i.e. when running on a HTTP server). You can override this behavior by manually instantiating one of the Zend\Console\Adapter\* classes; you should do this only as a last resort, however!

zend-mvc

If you are using MVC controllers you can obtain Console adapter instance using the ServiceManager.

namespace Application;

use Zend\Mvc\Controller\AbstractActionController;
use Zend\Console\Adapter\AdapterInterface as Console;
use Zend\Console\Exception\RuntimeException;

class ConsoleController extends AbstractActionController
{
    public function testAction()
    {
        $console = $this->getServiceLocator()->get('console');
        if (! $console instanceof Console) {
            throw new RuntimeException('Cannot obtain console adapter. Are we running in a
console?');
        }
    }
}

If you extend AbstractConsoleController, you can use the getConsole() method instead:

namespace Application;

use Zend\Mvc\Controller\AbstractConsoleController;
use Zend\Console\Exception\RuntimeException;

class ConsoleController extends AbstractConsoleController
{
    public function testAction()
    {
        $console = $this->getConsole();
    }
}

Use dependency injection

We recommend using dependency injection. Instead of pulling the console adapter from the service manager, inject it from within your controller's factory. This is essentially what happens when extending AbstractConsoleController already.

Using the console adapter

Zend\Console\Adapter\AdapterInterface describes a rich set of capabilities. Below is a sampling.

Window size and title

Method Description
$console->getWidth() (int) Get real console window width in characters.
$console->getHeight() (int) Get real console window height in characters.
$console->getSize() (array) Returns [$width, $height] with current console window dimensions.
$console->getTitle() (string) Get console window title.

Multibyte sequences

For UTF-8 enabled consoles, dimensions represent the number of multibyte characters (real characters).

Virtual buffer sizes

On consoles with virtual buffers (e.g. MS Windows Command Prompt), width and height represent visible (real) size, without scrolling the window. For example, if the window scrolling width is 120 chars, but its real, visible width is 80 chars, getWidth() will return 80.

Character set

Method Description
$console->isUtf8() (boolean) Is the console UTF-8 compatible (can it display unicode strings)?
$console->getCharset() (Zend\Console\Charset\CharsetInterface) This method will return an instance of one of the Zend\Console\Charset\* classes representing the readable charset present for line-drawing. It is automatically detected by the adapter.

Writing to the console

Method Description
$console->write(string $text, $color = null, $bgColor = null) Write $text to the console, optionally using foreground $color and background $bgColor. Color values must be one of the Zend\Console\ColorInterface constants.
$console->writeLine(string $text, $color = null, $bgColor = null) Write a single line of $text to the console. This method will output an environment-specific newline character at the end of the text, moving the console cursor to next line.
$console->writeAt(string $text, int $x, int $y, $color = null, $bgColor = null) Write $text at the specified $x and $y coordinates of console window. The top left corner of the screen has coordinates of $x = 1; $y = 1. To retrieve the far-right and bottom coordinates, use the getWidth() and getHeight() methods.

Reading from the console

Method Description
$console->readChar(string $mask = null) (string) Read a single character from the console. Optional (string) $mask can be provided to force entering only a selected set of characters. For example, to read a single digit, we can use the following syntax: $digit = $console->readChar('0123456789');.
$console->readLine(int $maxLength = 2048) (string) Read a single line of input from console. Optional (int) $maxLength can be used to limit the length of data that will be read. The line will be returned without trailing newline characters.

Miscellaneous

Method Description
$console->hideCursor() Hide blinking cursor from the console.
$console->showCursor() Show blinking cursor in the console.
$console->clear() Clear the screen.
$console->clearLine() Clear the line that the cursor currently sits at.