From 51128028f47b9c1b13966c0dbbb0c185e7f91c32 Mon Sep 17 00:00:00 2001
From: Hazelnoot <acomputerdog@gmail.com>
Date: Sat, 24 May 2025 22:00:57 -0400
Subject: [PATCH] add foreign keys to following where instance is referenced

---
 ...-add_instance_foreign_keys_to_following.js | 26 +++++++++++++++++++
 packages/backend/src/models/Following.ts      | 21 +++++++++++++++
 2 files changed, 47 insertions(+)
 create mode 100644 packages/backend/migration/1748137683887-add_instance_foreign_keys_to_following.js

diff --git a/packages/backend/migration/1748137683887-add_instance_foreign_keys_to_following.js b/packages/backend/migration/1748137683887-add_instance_foreign_keys_to_following.js
new file mode 100644
index 0000000000..8f4a977ff5
--- /dev/null
+++ b/packages/backend/migration/1748137683887-add_instance_foreign_keys_to_following.js
@@ -0,0 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: hazelnoot and other Sharkey contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+/**
+ * @typedef {import('typeorm').MigrationInterface} MigrationInterface
+ */
+
+/**
+ * @class
+ * @implements {MigrationInterface}
+ */
+export class AddInstanceForeignKeysToFollowing1748137683887 {
+	name = 'AddInstanceForeignKeysToFollowing1748137683887'
+
+	async up(queryRunner) {
+		await queryRunner.query(`ALTER TABLE "following" ADD CONSTRAINT "FK_following_followerHost" FOREIGN KEY ("followerHost") REFERENCES "instance"("host") ON DELETE CASCADE ON UPDATE NO ACTION`);
+		await queryRunner.query(`ALTER TABLE "following" ADD CONSTRAINT "FK_following_followeeHost" FOREIGN KEY ("followeeHost") REFERENCES "instance"("host") ON DELETE CASCADE ON UPDATE NO ACTION`);
+	}
+
+	async down(queryRunner) {
+		await queryRunner.query(`ALTER TABLE "following" DROP CONSTRAINT "FK_following_followeeHost"`);
+		await queryRunner.query(`ALTER TABLE "following" DROP CONSTRAINT "FK_following_followerHost"`);
+	}
+}
diff --git a/packages/backend/src/models/Following.ts b/packages/backend/src/models/Following.ts
index 62cbc29f26..0aa1b13976 100644
--- a/packages/backend/src/models/Following.ts
+++ b/packages/backend/src/models/Following.ts
@@ -4,6 +4,7 @@
  */
 
 import { PrimaryColumn, Entity, Index, JoinColumn, Column, ManyToOne } from 'typeorm';
+import { MiInstance } from '@/models/Instance.js';
 import { id } from './util/id.js';
 import { MiUser } from './User.js';
 
@@ -66,6 +67,16 @@ export class MiFollowing {
 	})
 	public followerHost: string | null;
 
+	@ManyToOne(() => MiInstance, {
+		onDelete: 'CASCADE',
+	})
+	@JoinColumn({
+		name: 'followerHost',
+		foreignKeyConstraintName: 'FK_following_followerHost',
+		referencedColumnName: 'host',
+	})
+	public followerInstance: MiInstance | null;
+
 	@Column('varchar', {
 		length: 512, nullable: true,
 		comment: '[Denormalized]',
@@ -85,6 +96,16 @@ export class MiFollowing {
 	})
 	public followeeHost: string | null;
 
+	@ManyToOne(() => MiInstance, {
+		onDelete: 'CASCADE',
+	})
+	@JoinColumn({
+		name: 'followeeHost',
+		foreignKeyConstraintName: 'FK_following_followeeHost',
+		referencedColumnName: 'host',
+	})
+	public followeeInstance: MiInstance | null;
+
 	@Column('varchar', {
 		length: 512, nullable: true,
 		comment: '[Denormalized]',