PHP-CLI记录进度/输出和捕获错误的最佳实践

Question

I am writing a PHP CLI tool. Tool has a number of command lines options available. It will be a class. I will load an instance and run the command with all the arguments passed in.

What are best ways to capture info messages as it progresses as well as catching errors and halting on errors with output to screen?

Whats the ideal PHP CLI example?

Answer 1

I use as a template something like this (for simple enough console scripts):

$inputFile = null;
$outputFile = null;
try {
    // Checking command-line arguments
    if (1 === $argc) {
        throw new Exception('Missing input file path.');
    }

    $inputFilePath = $argv[1];
    if (!file_exists($inputFilePath) || !is_readable($inputFilePath)) {
        throw new Exception('Input file does not exist or cannot be read.');
    }

    $inputFile = fopen($inputFilePath, 'r');

    if (2 < $argc) {
        $outputFilePath = $argv[2];
        if (!is_writable($outputFilePath)) {
            throw new Exception('Cannot write to output file.');
        }

        $outputFile = fopen($outputFilePath, 'w');
    } else {
        $outputFile = STDOUT;
    }

    // Do main process (reading data, processing, writing output data)
} catch (Exception $e) {
    // Show usage info, output error message

    fputs(STDERR, sprintf('USAGE: php %s inputFilePath [outputFilePath]', $argv[0]) . PHP_EOL);
    fputs(STDERR, 'ERROR: ' . $e->getMessage() . PHP_EOL);
}

// Free resources

if ($inputFile) {
    fclose($inputFile);
}

if ($outputFile) {
    fclose($outputFile);
}

Answer 2

I prefer to use a kind of observer-pattern for processing, and leave error-handling to the console application:

class ExampleService
{
    /**
     * @var array
     */
    private $params;

    public function __construct(array $params)
    {
        $this->params = $params;
    }

    /**
     * @param callable|null $listener
     */
    public function execute(callable $listener = null)
    {
        foreach (['long', 'term', 'loop'] as $item) {
            // do complex stuff
            $listener && $listener($item);
        }
    }
}

require_once __DIR__ . '/vendor/autoload.php';

use Symfony\Component\Console\Application;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

$app = new Application;
$app->add($command = new Command('example'));

$command->addOption('opt1');
$command->addArgument('arg1');
$command->setCode(function(InputInterface $input, OutputInterface $output) {
    $service = new ExampleService($input->getOptions() + $input->getArguments());
    $service->execute(function($messages) use($output){
        $output->writeln($messages);
    });
});

$app->run();