feat(migration): add the hosts of existing remote users to instances

priv/repo/migrations/20261028000000_backfill_instances_from_users.exs

@@ -0,0 +1,29 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2026 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Repo.Migrations.BackfillInstancesFromUsers do
+  use Ecto.Migration
+
+  # Remote users now create an instances row; add the hosts of existing ones,
+  # so the peer list can come from the instances table.
+  def up do
+    Pleroma.Repo.query!(
+      """
+      INSERT INTO instances (host, inserted_at, updated_at)
+      SELECT DISTINCT host, now(), now()
+      FROM (
+        SELECT substring(ap_id from '^[A-Za-z][A-Za-z0-9+.-]*://([^/:?#]+)') AS host
+        FROM users
+        WHERE local = false AND ap_id IS NOT NULL
+      ) AS hosts
+      WHERE host IS NOT NULL
+      ON CONFLICT (host) DO NOTHING
+      """,
+      [],
+      timeout: :infinity
+    )
+  end
+
+  def down, do: :ok
+end