praefect: Prune stale maintenance-style replication events

In release 15.0 we have stopped creating maintenance-style replication
events in favor of using a best-effort strategy for handling repository
maintenance. And while we still have the logic in place to dequeue these
events, they're currently ignored by Praefect altogether.

We're about to remove this fallback logic now, so let's make clear that
the replication queue really doesn't have any maintenance-style events
left by adding a migration that prunes any stale ones.

1 files changed, 27 insertions, 0 deletions

diff --git a/internal/praefect/datastore/migrations/20220520083313_remove_maintenance_replication_events.go b/internal/praefect/datastore/migrations/20220520083313_remove_maintenance_replication_events.go
new file mode 100644
index 000000000..09330c942
--- /dev/null
+++ b/internal/praefect/datastore/migrations/20220520083313_remove_maintenance_replication_events.go
@@ -0,0 +1,27 @@
+package migrations
+
+import migrate "github.com/rubenv/sql-migrate"
+
+func init() {
+	m := &migrate.Migration{
+		Id: "20220520083313_remove_maintenance_replication_events",
+		Up: []string{
+			`DELETE FROM replication_queue WHERE job->>'change' IN (
+				'gc',
+				'repack_full',
+				'repack_incremental',
+				'cleanup',
+				'pack_refs',
+				'write_commit_graph',
+				'midx_repack',
+				'optimize_repository',
+				'prune_unreachable_objects'
+			)`,
+		},
+		Down: []string{
+			// We cannot get this data back anymore.
+		},
+	}
+
+	allMigrations = append(allMigrations, m)
+}