zappyzep/backend/src/migrations/1617363975046-UpdateCounterTriggers.ts

import { MigrationInterface, QueryRunner, TableColumn, TableIndex } from "typeorm";
import { TableForeignKey } from "typeorm/index";

export class UpdateCounterTriggers1617363975046 implements MigrationInterface {
  public async up(queryRunner: QueryRunner): Promise<void> {
    // Since we're adding a non-nullable unique name column and existing triggers won't have that, clear the table first
    await queryRunner.query("DELETE FROM counter_triggers");

    await queryRunner.addColumns("counter_triggers", [
      new TableColumn({
        name: "name",
        type: "varchar",
        length: "255",
      }),

      new TableColumn({
        name: "reverse_comparison_op",
        type: "varchar",
        length: "16",
      }),

      new TableColumn({
        name: "reverse_comparison_value",
        type: "int",
      }),
    ]);

    // Drop foreign key for counter_id -- needed to be able to drop the following unique index
    await queryRunner.dropForeignKey("counter_triggers", "FK_6bb47849ec95c87e58c5d3e6ae1");

    // Index for ["counter_id", "comparison_op", "comparison_value"]
    await queryRunner.dropIndex("counter_triggers", "IDX_ddc8a6701f1234b926d35aebf3");

    await queryRunner.createIndex(
      "counter_triggers",
      new TableIndex({
        columnNames: ["counter_id", "name"],
        isUnique: true,
      }),
    );

    // Recreate foreign key for counter_id
    await queryRunner.createForeignKey(
      "counter_triggers",
      new TableForeignKey({
        columnNames: ["counter_id"],
        referencedTableName: "counters",
        referencedColumnNames: ["id"],
        onDelete: "CASCADE",
        onUpdate: "CASCADE",
      }),
    );
  }

  public async down(queryRunner: QueryRunner): Promise<void> {
    // Since we're going back to unique comparison op and comparison value in this reverse-migration,
    // clear table contents first so we don't run into any conflicts with triggers with different names but identical comparison op and comparison value
    await queryRunner.query("DELETE FROM counter_triggers");

    // Drop foreign key for counter_id -- needed to be able to drop the following unique index
    await queryRunner.dropForeignKey("counter_triggers", "FK_6bb47849ec95c87e58c5d3e6ae1");

    // Index for ["counter_id", "name"]
    await queryRunner.dropIndex("counter_triggers", "IDX_2ec128e1d74bedd0288b60cdd1");

    await queryRunner.createIndex(
      "counter_triggers",
      new TableIndex({
        columnNames: ["counter_id", "comparison_op", "comparison_value"],
        isUnique: true,
      }),
    );

    // Recreate foreign key for counter_id
    await queryRunner.createForeignKey(
      "counter_triggers",
      new TableForeignKey({
        columnNames: ["counter_id"],
        referencedTableName: "counters",
        referencedColumnNames: ["id"],
        onDelete: "CASCADE",
        onUpdate: "CASCADE",
      }),
    );

    await queryRunner.dropColumn("counter_triggers", "reverse_comparison_value");
    await queryRunner.dropColumn("counter_triggers", "reverse_comparison_op");
    await queryRunner.dropColumn("counter_triggers", "name");
  }
}