Swap pk for app-backend path, fix heartbeat task

Signed-off-by: lpete@vmware.com <lpete@vmware.com>

.changeset/yellow-trains-protect.md

@@ -7,6 +7,7 @@
 '@backstage/backend-tasks': patch
 '@backstage/plugin-app-backend': patch
 '@backstage/plugin-bazaar-backend': patch
+'@backstage/plugin-scaffolder-backend': patch
 ---
 
 Changes needed to support MySQL

plugins/app-backend/migrations/20211229105307_init.js

@@ -24,12 +24,12 @@ exports.up = async function up(knex) {
     table.comment(
       'A cache of static assets that where previously deployed and may still be lazy-loaded by clients',
     );
-    // setting to 64KB to account for long paths
     table
-      .string('path', 16383)
+      .uuid('id')
       .primary()
       .notNullable()
-      .comment('The path of the file');
+      .comment('Auto-generated ID of the asset');
+    table.text('path', 'text').notNullable().comment('The path of the file');
     table
       .dateTime('last_modified_at')
       .defaultTo(knex.fn.now())

plugins/scaffolder-backend/src/scaffolder/tasks/DatabaseTaskStore.ts

@@ -261,18 +261,21 @@ export class DatabaseTaskStore implements TaskStore {
     tasks: { taskId: string }[];
   }> {
     const { timeoutS } = options;
-
+    let heartbeatInterval = this.db.raw(`? - interval '${timeoutS} seconds'`, [
+      this.db.fn.now(),
+    ]);
+    if (this.db.client.config.client.includes('mysql')) {
+      heartbeatInterval = this.db.raw(
+        `date_sub(now(), interval ${timeoutS} second)`,
+      );
+    } else if (this.db.client.config.client.includes('sqlite3')) {
+      heartbeatInterval = this.db.raw(`datetime('now', ?)`, [
+        `-${timeoutS} seconds`,
+      ]);
+    }
     const rawRows = await this.db<RawDbTaskRow>('tasks')
       .where('status', 'processing')
-      .andWhere(
-        'last_heartbeat_at',
-        '<=',
-        this.db.client.config.client.includes('sqlite3')
-          ? this.db.raw(`datetime('now', ?)`, [`-${timeoutS} seconds`])
-          : this.db.raw(`? - interval '${timeoutS} seconds'`, [
-              this.db.fn.now(),
-            ]),
-      );
+      .andWhere('last_heartbeat_at', '<=', heartbeatInterval);
     const tasks = rawRows.map(row => ({
       taskId: row.id,
     }));