Part Entity

We already have starships showing up on the homepage thanks to the Starship entity we built in the last tutorial. But now, it's time to step up our game. We need to track the individual parts used in each Starship. Here's the plan: each part will belong to exactly one Starship, and each Starship will have many parts. But before we dive into relationships, we need to start simple: we need a new entity to keep track of these parts! Fire up your terminal, open a new tab (since our server is humming along in the other), and run:

symfony console make:entity

Call it StarshipPart, skip broadcasting, and give it a few fields: name will be a string and won't be nullable, price will be an integer (in credits, of course), and also won't be nullable. Lastly, add a notes field which will be a text type (so it can be longer), and will be nullable. Once you've added these fields, create a new migration for the entity by copying and pasting symfony console make:migration.

Running Migrations and Adding Timestamps

Now, if you check out your migrations, you'll see just the new one we created: I cleaned up the old migrations from the last course. So this one is all about StarshipPart. Run it with:

symfony console doctrine:migrations:migrate

The table is in the database! But there are two fields that I like to add to all my entities: createdAt and updatedAt. You can see these inside of Starship, under TimestampableEntity. Copy that, and paste right on top of StarshipPart. Both properties are automatically set thanks to a library we installed in the last tutorial. And because we added two new fields, we need a migration!

symfony console make:migration

Then migrate:

symfony console doctrine:migrations:migrate

Using Factories to Create Dummy Objects

In the last tutorial, we used a cool library called Foundry to quickly create a bunch of dummy data. We're going to do the same for StarshipPart. Step 1 - since we don't have one yet - is to generate a factory for the entity with:

symfony console make:factory

Go check it out in src/Factory/StarshipPartFactory.php. It added some defaults for each field, but we can make it more interesting. At the top of StarshipPartFactory, I'll paste in some code with example parts (you can grab this from the code block on this page). Also replace the return in defaults() with code that uses that data. Finally, use this in the fixtures. At the bottom, create 50 random parts using StarshipPartFactory::createMany(50). Back in the terminal, run:

symfony console doctrine:fixtures:load

Confirm that we want to vent the oxygen from our database, then check out the new parts with:

symfony console doctrine:query:sql

And then: select * from starship_part

And with just a few lines of delightful code, we have 50 random parts in the database. Next: let's start linking these parts to their respective ships by creating our first relationship: the all-important ManyToOne relationship.