Add support for pingable roles

src/migrations/1547293464842-CreatePingableRolesTable.ts

@@ -0,0 +1,49 @@
+import { MigrationInterface, QueryRunner, Table } from "typeorm";
+
+export class CreatePingableRolesTable1547293464842 implements MigrationInterface {
+  public async up(queryRunner: QueryRunner): Promise<any> {
+    await queryRunner.createTable(
+      new Table({
+        name: "pingable_roles",
+        columns: [
+          {
+            name: "id",
+            type: "int",
+            unsigned: true,
+            isGenerated: true,
+            generationStrategy: "increment",
+            isPrimary: true
+          },
+          {
+            name: "guild_id",
+            type: "bigint",
+            unsigned: true
+          },
+          {
+            name: "channel_id",
+            type: "bigint",
+            unsigned: true
+          },
+          {
+            name: "role_id",
+            type: "bigint",
+            unsigned: true
+          }
+        ],
+        indices: [
+          {
+            columnNames: ["guild_id", "channel_id"]
+          },
+          {
+            columnNames: ["guild_id", "channel_id", "role_id"],
+            isUnique: true
+          }
+        ]
+      })
+    );
+  }
+
+  public async down(queryRunner: QueryRunner): Promise<any> {
+    await queryRunner.dropTable("pingable_roles", true);
+  }
+}