Allow running dbal:run-sql using arbitrary connection

[delolmo]

Q	A
Type	feature
BC Break	no

Summary

This slight modification allows running the dbal:run-sql command using an arbitrary database connection, which is specially useful in CLI applications that use multiple database connections. Backwards compatibility is maintained by using the default 'db' value for the input option.

The command now includes a --connection option, which defaults to 'db'. If specified, a ConnectionHelper is searched for that matches the provided connection name.

[SenseException]

If specified, a ConnectionHelper is searched for that matches the provided connection name.

How do you add a new ConnectionHelper with a new connection in your use case? Can you please provide example code? This might be relevant because adding a new helper for another connection should become part of the documentation in scope of this PR if this gets approved.

[morozov]

There's another similar pull request #3956.

[delolmo]

How do you add a new ConnectionHelper with a new connection in your use case? Can you please provide example code? This might be relevant because adding a new helper for another connection should become part of the documentation in scope of this PR if this gets approved.

When defining a generic \Symfony\Component\Console\Application, a HelperSet may be passed through the setHelperSet method. In doctrine/migrations, e.g., a cli-config.php script is created returning a specific HelperSet which can be modified to include several ConnectionHelper's:

<?php

require 'vendor/autoload.php';

use Doctrine\DBAL\DriverManager;
use Doctrine\DBAL\Tools\Console\Helper\ConnectionHelper;
use Symfony\Component\Console\Helper\HelperSet;

$dbParams = include 'migrations-db.php';

$connection = DriverManager::getConnection($dbParams);

return new HelperSet([
    'db' => new ConnectionHelper($connection),
    'db.read' => new ConnectionHelper($connection), // for example
    'db.write' => new ConnectionHelper($connection), // for example
]);

For documentation purposes, I was thinking about the following example:

<?php

use Doctrine\DBAL\DriverManager;
use Doctrine\DBAL\Tools\Console\Helper\ConnectionHelper;
use Doctrine\DBAL\Tools\Console\Command\RunSqlCommand;
use Symfony\Component\Console\Application;
use Symfony\Component\Console\Helper\HelperSet;

$dbParams = [...]; // A multidimensional array with connection parameters

$cli = new Application('app name', 'app version');

$cli->setHelperSet(new HelperSet([
    'db.read' => new ConnectionHelper(
        DriverManager::getConnection($dbParams['db.read'])
    ),
    'db.write' => new ConnectionHelper(
        DriverManager::getConnection(($dbParams['db.write'])
    ),
    'pgsql' => new ConnectionHelper(
        DriverManager::getConnection($dbParams['db.pgsql'])
    ),
    'mysql' => new ConnectionHelper(
        DriverManager::getConnection(($dbParams['db.mysql'])
    ),
    // and so on...
]));

$cli->addCommand(new RunSqlCommand());

// Continue configuring your cli app, add commands, etc.

Regarding #3956, IMO its too much code to solve a very specific use case. Maybe, a new ConnectionProviderHelper could be created, but I still think its unnecessary.

I would be happy to add this same modification to the ReservedWordCommand, if we are in agreement.

[delolmo]

BTW I think I mentioned doctrine/migrations, but doctrine/dbal and doctrine/orm use a similar approach to define database connections.

doctrine/dbal expects a HelperSet to be returned by the cli-config.php file, while doctrine/orm uses a createHelperSet static method.

[dmaicher]

Either we go with this approach (which would be backwards compatible without deprecations) or we move forward with #3956

@morozov what do you think?

[morozov]

@dmaicher, I'd proceed with #3956.

[morozov]

Closing in favor of #3956.