Created migration which adds domains table

data/migrations/Version20190930165521.php

@@ -0,0 +1,55 @@
+<?php
+declare(strict_types=1);
+
+namespace ShlinkMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\DBAL\Schema\SchemaException;
+use Doctrine\DBAL\Schema\Table;
+use Doctrine\DBAL\Types\Type;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20190930165521 extends AbstractMigration
+{
+    /**
+     * @throws SchemaException
+     */
+    public function up(Schema $schema): void
+    {
+        $shortUrls = $schema->getTable('short_urls');
+        if ($shortUrls->hasColumn('domain_id')) {
+            return;
+        }
+
+        $domains = $schema->createTable('domains');
+        $domains->addColumn('id', Type::BIGINT, [
+            'unsigned' => true,
+            'autoincrement' => true,
+            'notnull' => true,
+        ]);
+        $domains->addColumn('authority', Type::STRING, [
+            'length' => 512,
+            'notnull' => true,
+        ]);
+        $domains->addUniqueIndex(['authority']);
+        $domains->setPrimaryKey(['id']);
+
+        $shortUrls->addColumn('domain_id', Type::BIGINT, [
+            'unsigned' => true,
+            'notnull' => false,
+        ]);
+        $shortUrls->addForeignKeyConstraint('domains', ['domain_id'], ['id'], [
+            'onDelete' => 'RESTRICT',
+            'onUpdate' => 'RESTRICT',
+        ]);
+    }
+
+    /**
+     * @throws SchemaException
+     */
+    public function down(Schema $schema): void
+    {
+        $schema->getTable('short_urls')->dropColumn('domain_id');
+        $schema->dropTable('domains');
+    }
+}