announcements: add start at edition date

workspaces/announcements/.changeset/flat-numbers-destroy.md

@@ -0,0 +1,11 @@
+---
+'@backstage-community/plugin-announcements-backend': minor
+'@backstage-community/plugin-announcements-common': minor
+'@backstage-community/plugin-announcements-react': minor
+'@backstage-community/plugin-announcements': minor
+---
+
+- Added a `start_at` field to allow users to set the date when an announcement occurred.
+- Announcements can now be sorted by `created_at` (default) or `start_at`, with customizable order (desc or asc).
+- Updated the New Announcement form to accommodate start_at and future fields.
+- Added `created_at` and `start_at` columns to the admin view table.

workspaces/announcements/plugins/announcements-backend/db/migrations/20250107203219_add_start_date.js

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2025 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @param { import("knex").Knex } knex
+ * @returns { Promise<void> }
+ */
+exports.up = async function up(knex) {
+  // Add the new column as nullable initially
+  await knex.schema.alterTable('announcements', table => {
+    table.timestamp('start_at').nullable();
+  });
+
+  // Backfill the start_at column with values from created_at
+  await knex('announcements').update({
+    start_at: knex.raw('created_at'),
+  });
+
+  // Alter the column to be not nullable
+  await knex.schema.alterTable('announcements', table => {
+    table.timestamp('start_at').notNullable().alter();
+  });
+};
+
+/**
+ * @param { import("knex").Knex } knex
+ * @returns { Promise<void> }
+ */
+exports.down = async function down(knex) {
+  await knex.schema.alterTable('announcements', table => {
+    table.dropColumn('start_at');
+  });
+};