webmozart/console

A usable, beautiful and easily testable console toolkit written in PHP.

1.0.0-beta5 2016-02-05 10:03 UTC

README

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Latest release: 1.0.0-beta5

PHP >= 5.3.9

A usable, beautiful and easily testable console toolkit written in PHP.

Goal

The goal of this package is:

  • to build PHP applications similar to the "git" command
  • with a minimum amount of code
  • that are testable
  • robust
  • and beautiful.

None of the existing console libraries matched these requirements, so I refactored the Symfony Console component into what you can see here.

Installation

Use Composer to install the package:

$ composer require webmozart/console:~1.0@beta

Basic Configuration

Console applications are configured via configuration classes. As example, we will create the "git" command in PHP:

use Webmozart\Console\Config\DefaultApplicationConfig;

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        parent::configure();
        
        $this
            ->setName('git')
            ->setVersion('1.0.0')
            
            // ...
        ;
    }
}

This basic configuration tells the console that the executable is called "git" and that the current version is 1.0.0. Let's create the "git" executable now:

#!/usr/bin/env php
<?php

use Webmozart\Console\ConsoleApplication;

if (file_exists($autoload = __DIR__.'/../../../autoload.php')) {
    require_once $autoload;
} else {
    require_once __DIR__.'/../vendor/autoload.php';
}

$cli = new ConsoleApplication(new GitApplicationConfig());
$cli->run();

The complicated autoload block makes sure that the autoload file is found both when you run the executable directly in your package and when your package is installed in another project via Composer.

Change the permissions of your executable and try to run it:

$ chmod a+x bin/git
$ bin/git
Git version 1.0.0
...

Commands

So far, our application doesn't do much. Let's add a command "log" that displays the latest commits:

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                ->setDescription('Show the latest commits')
                ->setHandler(new LogCommandHandler())
            ->end()
        ;
    }
}

As you can see, the execution of the command is delegated to a LogCommandHandler. Since the handler is a separate class, it can easily be tested in isolation. Let's implement a basic handler:

use Webmozart\Console\Api\Args\Args;
use Webmozart\Console\Api\Command\Command;
use Webmozart\Console\Api\IO\IO;

class LogCommandHandler
{
    public function handle(Args $args, IO $io, Command $command)
    {
        // Simulate the retrieval of the commits
        $commits = array(
            'commit1',
            'commit2',
            'commit3',
        );
        
        foreach ($commits as $commit) {
            $io->writeLine($commit);
        }
        
        return 0;
    }
}

The handle() method of our command handler retrieves up to three arguments:

  • Args $args: The arguments and options passed when calling the command.
  • IO $io: The I/O, which gives access to the standard input, the standard output and the error output.
  • Command $command: The currently executed command.

You can leave away the arguments that you don't need.

Every handler should return 0 if it was processed successfully and any integer between 1 and 255 if it failed.

Let's run the command:

$ bin/git log
commit1
commit2
commit3

Arguments

Next we'll add an argument <branch> to the "log" command with which we can select the branch to display:

use Webmozart\Console\Api\Args\Format\Argument;

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                // ...
                
                ->addArgument('branch', Argument::OPTIONAL, 'The branch to display', 'master')
            ->end()
        ;
    }
}

We added an optional argument "branch" with the default value "master". We can access the value of the argument through the Args instance in the handler:

class LogCommandHandler
{
    public function handle(Args $args, IO $io)
    {
        $io->writeLine('Branch: '.$args->getArgument('branch'));
        $io->writeLine('--');
        
        // ...
    }
}

Let's run the command with the argument:

$ bin/git log 1.0
Branch: 1.0
--
commit1
commit2
commit3

The second argument of the addArgument() method accepts a bitwise combination of different flags:

Constant Description
Argument::OPTIONAL The argument is optional. If you don't pass a default value, the default value is null.
Argument::REQUIRED The argument must be passed when calling the command.
Argument::MULTI_VALUED The argument may be passed multiple times. The command handler receives an array of all passed values.
Argument::STRING The argument is parsed as string (the default).
Argument::BOOLEAN The argument is parsed as boolean.
Argument::INTEGER The argument is parsed as integer.
Argument::FLOAT The argument is parsed as float.
Argument::NULLABLE Convert "null" to null.

Options

Options are additional, optional settings that you can pass to your command. Let's add the option --max=<limit> to our command which limits the number of displayed commits to the passed limit:

use Webmozart\Console\Api\Args\Format\Option;

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                // ...
                
                ->addOption('max', null, Option::REQUIRED_VALUE, 'The maximum number of commits', 25)
            ->end()
        ;
    }
}

The configuration of options is very similar to the configuration of arguments. We created a --max option, which requires a value. If the option is not set by the user, its value defaults to 25.

We can access the passed value with the getOption() method in our command handler:

class LogCommandHandler
{
    public function handle(Args $args, IO $io)
    {
        // ...
        
        $io->writeLine('Limit: '.$args->getOption('max').' commits');
        
        // ...
    }
}

Additionally, you will frequently need the isOptionSet() method, which tells you whether the user actually passed the option when calling the command.

Let's run the command with the option:

$ bin/git log --max 10
Branch: master
Limit: 10 commits
--
commit1
commit2
commit3

Options support short names that consist of a single character only. Instead of two leading dashes, short option names are only prefixed with one dash, for example: -m. Let's add this alias to our option by setting the second argument of the addOption() method:

use Webmozart\Console\Api\Args\Format\Option;

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                // ...
                
                ->addOption('max', 'm', Option::REQUIRED_VALUE, 'The maximum number of commits', 25)
            ->end()
        ;
    }
}

Now the command can also be run like this:

$ bin/git log -m 10

Like for arguments, options support a bitwise combination of different flags that control how the option is processed:

Constant Description
Option::NO_VALUE The option accepts no value. Used for simple on/off settings.
Option::OPTIONAL_VALUE The option accepts a value, but the value is option.
Option::REQUIRED_VALUE The option value needs to be set when passing the option.
Option::MULTI_VALUED The option may be passed multiple times. The command handler receives an array of all passed values.
Option::STRING The option is parsed as string (the default).
Option::BOOLEAN The option is parsed as boolean.
Option::INTEGER The option is parsed as integer.
Option::FLOAT The option is parsed as float.
Option::NULLABLE Convert "null" to null.
Option::PREFER_LONG_NAME The help lists the long form (--max) as suggested way of passing the option (the default).
Option::PREFER_SHORT_NAME The help lists the short form (-m) as suggested way of passing the option.

Dependencies

Very often, our command handlers rely on external services to access information or execute business logic. These services can be injected through the constructor of the command handler. For example, assume that we need a CommitRepository to access the commits listed in the "log" command:

class LogCommandHandler
{
    private $repository;
    
    public function __construct(CommitRepository $repository)
    {
        $this->repository = $repository;
    }
    
    public function handle(Args $args, IO $io)
    {
        $commits = $this->repository->findByBranch($args->getArgument('branch'));
        
        // ...
    }
}

Since the CommitRepository is injected into the command handler, we can easily replace the repository with a mock object when we test the handler.

We also need to change the configuration to inject the repository:

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                // ...
                
                ->setHandler(new LogCommandHandler(new CommitRepository()))
            ->end()
        ;
    }
}

If your application grows, a lot of objects will be created whenever the configure() method is executed - even if the commands that need these objects are not executed. Let's change our call to setHandler() to a closure so that the handler is executed on demand:

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('log')
                // ...
                
                ->setHandler(function () {
                    return new LogCommandHandler(new CommitRepository());
                })
            ->end()
        ;
    }
}

Now, the LogCommandHandler and its dependencies are only created when "log" command is executed.

Sub-Commands

The "log" command was a very simple example, but many real-world use cases are more complicated than that. Consider the "git remote" command, which is split into several sub-commands:

$ git remote
$ git remote add ...
$ git remote rename ...
$ git remote remove ...

Such sub-commands can be introduced with the beginSubCommand() method in the configuration:

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('remote')
                ->setDescription('Manage the remotes of your Git repository')
                ->setHandler(function () {
                    return new RemoteCommandHandler(new RemoteManager());
                })
                
                ->beginSubCommand('list')
                    ->setHandlerMethod('handleList')
                ->end()
                
                ->beginSubCommand('add')
                    ->setHandlerMethod('handleAdd')
                    ->addArgument('name', Argument::REQUIRED, 'The remote name')
                    ->addArgument('url', Argument::REQUIRED, 'The remote URL')
                ->end()
                
                // ...
            ->end()
        ;
    }
}

Like regular commands, sub-commands accept options, arguments and command handlers. However, instead of creating one command handler per sub-command, it is often more convenient to create a single handler with one method per sub-command. The handler method can be selected with setHandlerMethod().

The basic implementation of our RemoteCommandHandler is very similar to the command handler of the "log" command:

class RemoteCommandHandler
{
    private $manager;
    
    public function __construct(RemoteManager $manager)
    {
        $this->manager = $manager;
    }
    
    public function handleList(Args $args, IO $io)
    {
        $remotes = $this->manager->getRemotes();
        
        // ...
        
        return 0;
    }
    
    public function handleAdd(Args $args)
    {
        $name = $args->getArgument('name');
        $url = $args->getArgument('url');
        
        $this->manager->addRemote($name, $url);
        
        return 0;
    }
}

If we inject a working RemoteManager, we can execute both commands now:

$ git remote add origin http://example.com
$ git remote list

If we want to execute the "list" command by default if no sub-command is selected, we need to mark it as default command with markDefault():

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->beginCommand('remote')
                // ...
                
                ->beginSubCommand('list')
                    // ...
                    
                    ->markDefault()
                ->end()
                
                // ...
            ->end()
        ;
    }
}

Now we can run the list command with:

$ git remote

At last, you can use markAnonymous() if you want to run the command just with git remote, but not with git remote list.

Colors and Styles

The console supports colors and styles in the output that you pass to the IO class. Let's output some bold text for example:

$io->writeLine("Current branch: <b>$branch</b>");

Just like in HTML, the styles are inserted in your text using markup tags. The following styles are defined by default:

Tag Description
<b> Bold text
<u> Underlined text
<bu> Bold and underlined text
<c1> Colored text (default: cyan)
<c2> Colored text (default: yellow)
<warn> Black text with a yellow background
<error> White text with a red background

You can change the existing styles or add custom styles using the addStyle() method in your configuration:

use Webmozart\Console\Api\Formatter\Style;

class GitApplicationConfig extends DefaultApplicationConfig
{
    protected function configure()
    {
        $this
            // ...
            
            ->addStyle(Style::tag('c3')->fgMagenta())
        ;
    }
}

Here is a list of methods that can be called on the Style class:

Method Description
bold() Bold text
underlined() Underlined text
blinking() Blinking text
inverse() Invert the foreground and background color
hidden() Hidden text
fgDefault() Use the system's default text color
fgBlack() Black text
fgRed() Red text
fgGreen() Green text
fgYellow() Yellow text
fgBlue() Blue text
fgMagenta() Magenta text
fgCyan() Cyan text
fgWhite() White text
bgDefault() Use the system's default background color
bgBlack() Black background
bgRed() Red background
bgGreen() Green background
bgYellow() Yellow background
bgBlue() Blue background
bgMagenta() Magenta background
bgCyan() Cyan background
bgWhite() White background

Tables

You can draw tables with the Table class:

use Webmozart\Console\UI\Component\Table;

$table = new Table();

$table->setHeaderRow(array('Remote Name', 'Remote URL'));

foreach ($remotes as $remote) {
    $table->addRow(array($remote->getName(), $remote->getUrl()));
}

$table->render($io);

Tables support word wrapping, so that overlong text does not break the output. The default output of the above table is similar to this:

+-------------+-------------------------------+
| Remote Name | Remote URL                    |
+-------------+-------------------------------+
| origin      | http://example.com/repository |
| fork        | http://fork.com/repository    |
+-------------+-------------------------------+

You can change the style of the table by passing a custom TableStyle to the constructor. Either build your own TableStyle or use one of the predefined ones:

use Webmozart\Console\UI\Component\Table;
use Webmozart\Console\UI\Component\TableStyle;

$table = new Table(TableStyle::solidBorder());
┌──────────────┬───────────────────────────────┐
│ Remote Name  │ Remote URL                    │
├──────────────┼───────────────────────────────┤
│ origin       │ http://example.com/repository │
│ fork         │ http://fork.com/repository    │
└──────────────┴───────────────────────────────┘

The following predefined table styles exist:

Style Description
TableStyle::asciiBorder() Uses ASCII characters for the border (the default)
TableStyle::solidBorder() Uses Unicode characters for the border
TableStyle::borderless() No border

Using Symfony Helpers

Since this library is a complete refactor of the Symfony Console component you can not use the Symfony Console helpers out of the box. If you want to use them you need to wrap the input and output accordingly:

use Webmozart\Console\Adapter\ArgsInput;
use Webmozart\Console\Adapter\IOOutput;

$colors = $helper->ask(new ArgsInput($args->getRawArgs(), $args), new IOOutput($io), $question);

If you find this to cumbersome and you use it many times in your code, consider using traits:

use Webmozart\Console\Adapter\ArgsInput;
use Webmozart\Console\Adapter\IOOutput;

trait QuestionTrait
{
    protected function ask(Args $args, IO $io, Question $question)
    {
        // You could cache these instances, but you probably won't need it
        $helper = new QuestionHelper();

        return $helper->ask(new ArgsInput($args->getRawArgs(), $args), new IOOutput($io), $question);
    }
}

class MyCommandHandler
{
    use QuestionTrait;

    public function handle(Args $args, IO $io)
    {
        $question = new ChoiceQuestion(
            'Please select your favorite colors (defaults to red and blue)',
            array('red', 'blue', 'yellow'),
            '0,1'
        );

        $question->setMultiselect(true);

        $colors = $this->ask($args, $io, $question);
    }
}

Authors

Contribute

Contributions to are very welcome!

Support

If you are having problems, send a mail to bschussek@gmail.com or shout out to @webmozart on Twitter.

License

All contents of this package are licensed under the MIT license.