Reference
In This Article
Console Helper
Writing one-off scripts or vendor binaries for a package is often problematic:
- You need to parse arguments manually.
- You need to send output to the console in a meaningful fashion:
- Using
STDOUT
for meaningful, expected output - Using
STDERR
for error messages - Ensuring any line breaks are converted to
PHP_EOL
- Optionally, using console colors to provide context, which means:
- Detecting whether or not the console supports colors in the first place
- Providing appropriate escape sequences to produce color
- Using
Zend\Stdlib\ConsoleHelper
helps to address the second major bullet point and
all beneath it in a minimal fashion.
Usage
Typical usage is to instantiate a ConsoleHelper
, and call one of its methods:
use Zend\Stdlib\ConsoleHelper;
$helper = new ConsoleHelper();
$helper->writeLine('This is output');
You can optionally pass a PHP stream resource to the constructor, which will be used to determine whether or not color support is available:
$helper = new ConsoleHelper($stream);
By default, it assumes STDOUT
, and tests against that.
Available methods
ConsoleHelper
provides the following methods.
colorize
colorize(string $string) : string
colorize()
accepts a formatted string, and will then apply ANSI color
sequences to them, if color support is detected.
The following sequences are currently supported:
<info>...</info>
will apply a green color sequence around the provided text.<error>...</error>
will apply a red color sequence around the provided text.
You may mix multiple sequences within the same stream.
write
write(string $string, bool $colorize = true, resource $stream = STDOUT) : void
Emits the provided $string
to the provided $stream
(which defaults to
STDOUT
if not provided). Any EOL sequences are convered to PHP_EOL
. If
$colorize
is true
, the string is first passed to colorize()
as well.
writeline
writeLine(string $string, bool $colorize = true, resource $stream = STDOUT) : void
Same as write()
, except it also appends a PHP_EOL
sequence to the $string
.
writeErrorMessage
writeErrorMessage(string $message)
Wraps $message
in an <error></error>
sequence, and passes it to
writeLine()
, using STDERR
as the $stream
.
Example
Below is an example class that accepts an argument list, and determines how and what to emit.
namespace Foo;
use Zend\Stdlib\ConsoleHelper;
class HelloWorld
{
private $helper;
public function __construct(ConsoleHelper $helper = null)
{
$this->helper = $helper ?: new ConsoleHelper();
}
public function __invoke(array $args)
{
if (! count($args)) {
$this->helper->writeErrorMessage('Missing arguments!');
return;
}
if (count($args) > 1) {
$this->helper->writeErrorMessage('Too many arguments!');
return;
}
$target = array_shift($args);
$this->helper->writeLine(sprintf(
'<info>Hello</info> %s',
$target
));
}
}
When to upgrade
ConsoleHelper
is deliberately simple, and assumes that your primary need for
console tooling is for output considerations.
If you need to parse complex argument strings, we recommend using zend-console/zf-console or symfony/console, as these packages provide those capabilities, as well as far more colorization and console feature detection facilities.
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