Create enum for user role

src/migrations/1701234567890-ConvertRoleToEnum.ts

@@ -0,0 +1,44 @@
+import { MigrationInterface, QueryRunner } from "typeorm";
+
+/**
+ * Migration to convert role column from varchar to enum
+ *
+ * File name should be: TIMESTAMP-ConvertRoleToEnum.ts
+ * Example: 1701234567890-ConvertRoleToEnum.ts
+ *
+ * Place in: src/migrations/
+ */
+export class ConvertRoleToEnum1701234567890 implements MigrationInterface {
+    public async up(queryRunner: QueryRunner): Promise<void> {
+        await queryRunner.query(`
+      DO $$ BEGIN
+        CREATE TYPE user_role_enum AS ENUM ('user', 'admin');
+      EXCEPTION
+        WHEN duplicate_object THEN null;
+      END $$;
+    `);
+
+        await queryRunner.query(`
+      ALTER TABLE "user" 
+      ALTER COLUMN "role" TYPE user_role_enum 
+      USING "role"::user_role_enum;
+    `);
+
+        await queryRunner.query(`
+      ALTER TABLE "user" 
+      ALTER COLUMN "role" SET DEFAULT 'user';
+    `);
+    }
+
+    public async down(queryRunner: QueryRunner): Promise<void> {
+        await queryRunner.query(`
+      ALTER TABLE "user" 
+      ALTER COLUMN "role" TYPE varchar 
+      USING "role"::text;
+    `);
+
+        await queryRunner.query(`
+      DROP TYPE IF EXISTS user_role_enum;
+    `);
+    }
+}