Merge pull request #484 from rbino/enhance-reconciliation

reconciler: normalize triggers before comparing them

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [0.8.0] - Unreleased
 ### Changed
 - Configure cookie attribute based on protocol.
+- Normalize triggers when comparing them for reconciliation to avoid useless reconciliations.
 
 ## [0.8.0-rc.1] - 2024-03-22
 ### Fixed

backend/lib/edgehog/tenants/reconciler/core.ex

@@ -68,10 +68,10 @@ defmodule Edgehog.Tenants.Reconciler.Core do
 
     case Astarte.fetch_trigger(client, trigger_name) do
       {:ok, existing_trigger} ->
-        if existing_trigger != required_trigger do
-          update_trigger!(client, trigger_name, required_trigger)
-        else
+        if trigger_matches?(existing_trigger, required_trigger) do
           :ok
+        else
+          update_trigger!(client, trigger_name, required_trigger)
         end
 
       # This intentionally doesn't match on different errors since we want to crash
@@ -120,4 +120,21 @@ defmodule Edgehog.Tenants.Reconciler.Core do
 
     :ok
   end
+
+  defp trigger_matches?(required, existing) do
+    normalize_defaults(required) == normalize_defaults(existing)
+  end
+
+  defp normalize_defaults(trigger) do
+    trigger
+    |> drop_if_default(["action", "ignore_ssl_errors"], false)
+    |> drop_if_default(["action", "http_static_headers"], %{})
+  end
+
+  defp drop_if_default(trigger, path, default) do
+    case pop_in(trigger, path) do
+      {^default, no_default_trigger} -> no_default_trigger
+      {_not_default, _} -> trigger
+    end
+  end
 end

backend/test/edgehog/tenants/reconciler/core_test.exs

@@ -249,6 +249,26 @@ defmodule Edgehog.Tenants.Reconciler.CoreTest do
       assert :ok = Core.reconcile_trigger!(client, trigger_map)
     end
 
+    test "works even if Astarte returns the trigger without some defaults", ctx do
+      %{
+        client: client,
+        trigger_name: trigger_name,
+        trigger_map: trigger_map
+      } = ctx
+
+      Edgehog.Astarte.Realm.TriggersMock
+      |> expect(:get, fn ^client, ^trigger_name ->
+        {_, no_ignore_ssl_errors_map} = pop_in(trigger_map["action"]["ignore_ssl_errors"])
+        {_, no_defaults_map} = pop_in(no_ignore_ssl_errors_map["action"]["http_static_headers"])
+
+        {:ok, %{"data" => no_defaults_map}}
+      end)
+      |> expect(:create, 0, fn _client, _trigger_map -> :ok end)
+      |> expect(:delete, 0, fn _client, _trigger_name -> :ok end)
+
+      assert :ok = Core.reconcile_trigger!(client, trigger_map)
+    end
+
     test "deletes and recreates the trigger if it differs from the required one", ctx do
       %{
         client: client,