Many To Many with Foundry

Remember back in AppFixtures when we manually assigned a Droid to a Starship? That was fun! But now, I want to create an army of droids, a fleet of starships and assign them all at once.

Get rid of those manual Droid and Starship assignments in AppFixtures.

Creating the Droid Army and Starship Fleet

Zoom to the bottom where we create starships and parts. We also now need a bunch of droids: DroidFactory::createMany(100).

Below, set droids to DroidFactory::randomRange(1, 5). This will assign anywhere between 1 and 5 random droids to each Starship.

The Magic of Symfony

Maybe you noticed something: we're setting a droids property here, but in Starship, we do not have a setDroids() method! Normally, this would trigger an angry error. But it will work! Foundry sees that we have an addDroid() method, and it calls that instead, one-by-one for each Droid.

Test Run

Time to see this in action! Find your terminal and run:

symfony console doctrine:fixtures:load

No errors? I'm a bit surprised, ahem, delighted too. Take a peek at the droids with:

symfony console doctrine:query:sql 'SELECT * FROM droid'

100 zany, adorable droids. Also check out the starship_droid table:

symfony console doctrine:query:sql 'SELECT * FROM starship_droid'

It should look like there's a random set of droids assigned to each starship

Hold Up, Something's Not Right!

But wait a minute. These "random" droids - could you sense my sarcastic air quotes? - aren't random at all! They're the 3 same droids over and over again. The problem is that randomRange(1, 5) is only called once: so it's assigning the same 1 to 5 random droids to every Starship. Not quite the variety we were hoping for.

Closures & Foundry

Fix this by passing a closure: StarshipFactory::createMany(), 100, fn() => [ 'droids' => DroidFactory::randomRange(1, 5)])

Foundry will execute the callback for all 100 starships. This means randomRange(1, 5) will be called 100 times, giving us a truly random range for each ship.

Give it a whirl! Re-run the fixtures and load the SQL query:

symfony console doctrine:fixtures:load
symfony console doctrine:query:sql 'SELECT * FROM starship_droid'

Then bask in the glory of a truly random set of droids assigned to starships.

We could have also fixed this by moving the droids key into StarshipFactory down in the defaults() method. But I like to keep defaults() for the required properties. And since droids are not technically required - good luck cleaning the bathroom without them! - I like to keep them out of defaults() and set them where we're using StarshipFactory.

Next, we'll learn how to JOIN across ManyToMany relationships. Once again, Doctrine handles the heavy lifting for us.