From f244b58916334a38151181918cace632b0becabe Mon Sep 17 00:00:00 2001
From: Tomasz Szuba <tszuba@box.com>
Date: Mon, 13 Feb 2023 18:19:37 +0100
Subject: [PATCH 1/2] Add new index to techinsights

This improved query for latest facts from several seconds to milliseconds on our instance

Signed-off-by: Tomasz Szuba <tszuba@box.com>
---
 .changeset/grumpy-bikes-begin.md              |  5 +++
 plugins/tech-insights-backend/knexfile.js     | 26 ++++++++++++++
 .../20230213170839_latest-facts-index.js      | 36 +++++++++++++++++++
 3 files changed, 67 insertions(+)
 create mode 100644 .changeset/grumpy-bikes-begin.md
 create mode 100644 plugins/tech-insights-backend/knexfile.js
 create mode 100644 plugins/tech-insights-backend/migrations/20230213170839_latest-facts-index.js

diff --git a/.changeset/grumpy-bikes-begin.md b/.changeset/grumpy-bikes-begin.md
new file mode 100644
index 0000000000..a98e6651f5
--- /dev/null
+++ b/.changeset/grumpy-bikes-begin.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-tech-insights-backend': patch
+---
+
+Add DB index to improve latency of latest fact query
diff --git a/plugins/tech-insights-backend/knexfile.js b/plugins/tech-insights-backend/knexfile.js
new file mode 100644
index 0000000000..b771c202f5
--- /dev/null
+++ b/plugins/tech-insights-backend/knexfile.js
@@ -0,0 +1,26 @@
+/*
+ * Copyright 2023 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.
+ */
+
+// This file makes it possible to run "yarn knex migrate:make some_file_name"
+// to assist in making new migrations
+module.exports = {
+  client: 'better-sqlite3',
+  connection: ':memory:',
+  useNullAsDefault: true,
+  migrations: {
+    directory: './migrations',
+  },
+};
diff --git a/plugins/tech-insights-backend/migrations/20230213170839_latest-facts-index.js b/plugins/tech-insights-backend/migrations/20230213170839_latest-facts-index.js
new file mode 100644
index 0000000000..94a589f59d
--- /dev/null
+++ b/plugins/tech-insights-backend/migrations/20230213170839_latest-facts-index.js
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2023 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.
+ */
+
+const indexName = 'fact_id_entity_timestamp_idx';
+/**
+ * @param { import("knex").Knex } knex
+ * @returns { Promise<void> }
+ */
+exports.up = async knex => {
+  await knex.schema.alterTable('facts', table => {
+    table.index(['id', 'entity', 'timestamp'], indexName);
+  });
+};
+
+/**
+ * @param { import("knex").Knex } knex
+ * @returns { Promise<void> }
+ */
+exports.down = async knex => {
+  await knex.schema.alterTable('facts', table => {
+    table.dropIndex(indexName);
+  });
+};

From 207d8df70300f794310562208a9d0f667c0ec0aa Mon Sep 17 00:00:00 2001
From: Tomasz Szuba <tszuba@box.com>
Date: Tue, 14 Feb 2023 10:51:33 +0100
Subject: [PATCH 2/2] Remove knexfile.js from tech-insights-backend

Signed-off-by: Tomasz Szuba <tszuba@box.com>
---
 plugins/tech-insights-backend/knexfile.js | 26 -----------------------
 1 file changed, 26 deletions(-)
 delete mode 100644 plugins/tech-insights-backend/knexfile.js

diff --git a/plugins/tech-insights-backend/knexfile.js b/plugins/tech-insights-backend/knexfile.js
deleted file mode 100644
index b771c202f5..0000000000
--- a/plugins/tech-insights-backend/knexfile.js
+++ /dev/null
@@ -1,26 +0,0 @@
-/*
- * Copyright 2023 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.
- */
-
-// This file makes it possible to run "yarn knex migrate:make some_file_name"
-// to assist in making new migrations
-module.exports = {
-  client: 'better-sqlite3',
-  connection: ':memory:',
-  useNullAsDefault: true,
-  migrations: {
-    directory: './migrations',
-  },
-};