Add ReleaseMetadata entity

Why ReleaseMetadata and not simply Metadata you ask? Because I want to
be sure future entities may have their own type of metadata and not have
name conflicts.

Why not adding this data to Release? I don't know, I like small tables
for the main entities I guess, probably #DoesNotScale.

migrations/Version20231001125432.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20231001125432 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return '';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // this up() migration is auto-generated, please modify it to your needs
+        $this->addSql('CREATE SEQUENCE release_metadata_id_seq INCREMENT BY 1 MINVALUE 1 START 1');
+        $this->addSql('CREATE TABLE release_metadata (id INT NOT NULL, release_id INT NOT NULL, year INT DEFAULT NULL, PRIMARY KEY(id))');
+        $this->addSql('CREATE UNIQUE INDEX UNIQ_1414EF75B12A727D ON release_metadata (release_id)');
+        $this->addSql('ALTER TABLE release_metadata ADD CONSTRAINT FK_1414EF75B12A727D FOREIGN KEY (release_id) REFERENCES release (id) NOT DEFERRABLE INITIALLY IMMEDIATE');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('CREATE SCHEMA public');
+        $this->addSql('DROP SEQUENCE release_metadata_id_seq CASCADE');
+        $this->addSql('ALTER TABLE release_metadata DROP CONSTRAINT FK_1414EF75B12A727D');
+        $this->addSql('DROP TABLE release_metadata');
+    }
+}

src/Entity/Release.php

@@ -25,6 +25,9 @@ class Release
     #[ORM\JoinColumn(nullable: false)]
     private ?User $owner = null;
 
+    #[ORM\OneToOne(mappedBy: 'release', cascade: ['persist', 'remove'])]
+    private ?ReleaseMetadata $metadata = null;
+
     public function __construct()
     {
         $this->artists = new ArrayCollection();
@@ -82,4 +85,21 @@ class Release
 
         return $this;
     }
+
+    public function getMetadata(): ?ReleaseMetadata
+    {
+        return $this->metadata;
+    }
+
+    public function setMetadata(ReleaseMetadata $metadata): static
+    {
+        // set the owning side of the relation if necessary
+        if ($metadata->getRelease() !== $this) {
+            $metadata->setRelease($this);
+        }
+
+        $this->metadata = $metadata;
+
+        return $this;
+    }
 }

src/Entity/ReleaseMetadata.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace App\Entity;
+
+use App\Repository\ReleaseMetadataRepository;
+use Doctrine\ORM\Mapping as ORM;
+
+/**
+ * Metadata related to a release.
+ *
+ * Could be pulled from an external source (MusicBrainz, Discogs, …) or filled by hand. A release should be usable
+ * without associated metadata, but these metadata should always have a 1-1 relation to an existing release.
+ */
+#[ORM\Entity(repositoryClass: ReleaseMetadataRepository::class)]
+class ReleaseMetadata
+{
+    #[ORM\Id]
+    #[ORM\GeneratedValue]
+    #[ORM\Column]
+    private ?int $id = null;
+
+    #[ORM\OneToOne(inversedBy: 'metadata', cascade: ['persist', 'remove'])]
+    #[ORM\JoinColumn(nullable: false)]
+    private ?Release $release = null;
+
+    #[ORM\Column(nullable: true)]
+    private ?int $year = null;
+
+    public function getId(): ?int
+    {
+        return $this->id;
+    }
+
+    public function getRelease(): ?Release
+    {
+        return $this->release;
+    }
+
+    public function setRelease(Release $release): static
+    {
+        $this->release = $release;
+
+        return $this;
+    }
+
+    public function getYear(): ?int
+    {
+        return $this->year;
+    }
+
+    public function setYear(?int $year): static
+    {
+        $this->year = $year;
+
+        return $this;
+    }
+}

src/Repository/ReleaseMetadataRepository.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Repository;
+
+use App\Entity\ReleaseMetadata;
+use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
+use Doctrine\Persistence\ManagerRegistry;
+
+/**
+ * @extends ServiceEntityRepository<ReleaseMetadata>
+ *
+ * @method ReleaseMetadata|null find($id, $lockMode = null, $lockVersion = null)
+ * @method ReleaseMetadata|null findOneBy(array $criteria, array $orderBy = null)
+ * @method ReleaseMetadata[]    findAll()
+ * @method ReleaseMetadata[]    findBy(array $criteria, array $orderBy = null, $limit = null, $offset = null)
+ */
+class ReleaseMetadataRepository extends ServiceEntityRepository
+{
+    public function __construct(ManagerRegistry $registry)
+    {
+        parent::__construct($registry, ReleaseMetadata::class);
+    }
+}