fix: (azure)machinepools: stop continuous reconciliation of resources by sorting ProviderIDs

Author: damdo

azure/scope/machinepool.go

@@ -21,6 +21,7 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
+	"slices"
 	"strings"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/authorization/armauthorization/v2"
@@ -357,6 +358,9 @@ func (m *MachinePoolScope) updateReplicasAndProviderIDs(ctx context.Context) err
 		providerIDs[i] = machine.Spec.ProviderID
 	}
 
+	// Sort providerIDs to ensure deterministic ordering to prevent continuous reconciliation.
+	slices.Sort(providerIDs)
+
 	m.AzureMachinePool.Status.Replicas = readyReplicas
 	m.AzureMachinePool.Spec.ProviderIDList = providerIDs
 	return nil

controllers/azuremanagedmachinepool_reconciler.go

@@ -19,6 +19,7 @@ package controllers
 import (
 	"context"
 	"fmt"
+	"slices"
 	"time"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v5"
@@ -164,6 +165,8 @@ func (s *azureManagedMachinePoolService) Reconcile(ctx context.Context) error {
 		providerIDs[i] = providerID
 	}
 
+	// Sort providerIDs to ensure deterministic ordering to prevent continuous reconciliation.
+	slices.Sort(providerIDs)
 	s.scope.SetAgentPoolProviderIDList(providerIDs)
 	s.scope.SetAgentPoolReplicas(int32(len(providerIDs)))
 	s.scope.SetAgentPoolReady(true)