From f95b9bd9ae072f81548d23b27a9ae3db5d82de7a Mon Sep 17 00:00:00 2001
From: Rahul Sharma <rahsharm@akamai.com>
Date: Wed, 13 Nov 2024 07:29:09 +0000
Subject: [PATCH] remove vpc from cache if it doesn't exist

---
 cloud/linode/instances.go        | 16 +++++-----------
 cloud/linode/route_controller.go | 16 ++++------------
 cloud/linode/vpc.go              | 25 +++++++++++++++++++++++--
 3 files changed, 32 insertions(+), 25 deletions(-)

diff --git a/cloud/linode/instances.go b/cloud/linode/instances.go
index 80c4853f..358aa569 100644
--- a/cloud/linode/instances.go
+++ b/cloud/linode/instances.go
@@ -85,22 +85,16 @@ func (nc *nodeCache) refreshInstances(ctx context.Context, client client.Client)
 		if vpcName == "" {
 			continue
 		}
-		vpcID, err := GetVPCID(client, strings.TrimSpace(vpcName))
+		resp, err := GetVPCIPAddresses(ctx, client, vpcName)
 		if err != nil {
 			klog.Errorf("failed updating instances cache for VPC %s. Error: %s", vpcName, err.Error())
 			continue
 		}
-		if vpcID != 0 {
-			resp, err := client.ListVPCIPAddresses(ctx, vpcID, linodego.NewListOptions(0, ""))
-			if err != nil {
-				return err
-			}
-			for _, r := range resp {
-				if r.Address == nil {
-					continue
-				}
-				vpcNodes[r.LinodeID] = append(vpcNodes[r.LinodeID], *r.Address)
+		for _, r := range resp {
+			if r.Address == nil {
+				continue
 			}
+			vpcNodes[r.LinodeID] = append(vpcNodes[r.LinodeID], *r.Address)
 		}
 	}
 
diff --git a/cloud/linode/route_controller.go b/cloud/linode/route_controller.go
index fbfe9bcb..8b3bdf47 100644
--- a/cloud/linode/route_controller.go
+++ b/cloud/linode/route_controller.go
@@ -27,12 +27,12 @@ type routeCache struct {
 }
 
 // RefreshCache checks if cache has expired and updates it accordingly
-func (rc *routeCache) refreshRoutes(ctx context.Context, client client.Client) error {
+func (rc *routeCache) refreshRoutes(ctx context.Context, client client.Client) {
 	rc.Mu.Lock()
 	defer rc.Mu.Unlock()
 
 	if time.Since(rc.lastUpdate) < rc.ttl {
-		return nil
+		return
 	}
 
 	vpcNodes := map[int][]linodego.VPCIP{}
@@ -42,15 +42,11 @@ func (rc *routeCache) refreshRoutes(ctx context.Context, client client.Client) e
 		if vpcName == "" {
 			continue
 		}
-		vpcID, err := GetVPCID(client, strings.TrimSpace(vpcName))
+		resp, err := GetVPCIPAddresses(ctx, client, vpcName)
 		if err != nil {
 			klog.Errorf("failed updating cache for VPC %s. Error: %s", vpcName, err.Error())
 			continue
 		}
-		resp, err := client.ListVPCIPAddresses(ctx, vpcID, linodego.NewListOptions(0, ""))
-		if err != nil {
-			return err
-		}
 		for _, r := range resp {
 			vpcNodes[r.LinodeID] = append(vpcNodes[r.LinodeID], r)
 		}
@@ -58,7 +54,6 @@ func (rc *routeCache) refreshRoutes(ctx context.Context, client client.Client) e
 
 	rc.routes = vpcNodes
 	rc.lastUpdate = time.Now()
-	return nil
 }
 
 type routes struct {
@@ -104,10 +99,7 @@ func (r *routes) instanceRoutesByID(id int) ([]linodego.VPCIP, error) {
 // getInstanceRoutes returns routes for given instance id
 // It refreshes routeCache if it has expired
 func (r *routes) getInstanceRoutes(ctx context.Context, id int) ([]linodego.VPCIP, error) {
-	if err := r.routeCache.refreshRoutes(ctx, r.client); err != nil {
-		return nil, err
-	}
-
+	r.routeCache.refreshRoutes(ctx, r.client)
 	return r.instanceRoutesByID(id)
 }
 
diff --git a/cloud/linode/vpc.go b/cloud/linode/vpc.go
index fa505523..274904aa 100644
--- a/cloud/linode/vpc.go
+++ b/cloud/linode/vpc.go
@@ -3,10 +3,12 @@ package linode
 import (
 	"context"
 	"fmt"
+	"strings"
 	"sync"
 
 	"github.com/linode/linode-cloud-controller-manager/cloud/linode/client"
 	"github.com/linode/linodego"
+	"k8s.io/klog/v2"
 )
 
 var (
@@ -35,7 +37,7 @@ func GetAllVPCIDs() []int {
 }
 
 // GetVPCID returns the VPC id of given VPC label
-func GetVPCID(client client.Client, vpcName string) (int, error) {
+func GetVPCID(ctx context.Context, client client.Client, vpcName string) (int, error) {
 	Mu.Lock()
 	defer Mu.Unlock()
 
@@ -43,7 +45,7 @@ func GetVPCID(client client.Client, vpcName string) (int, error) {
 	if vpcid, ok := vpcIDs[vpcName]; ok {
 		return vpcid, nil
 	}
-	vpcs, err := client.ListVPCs(context.TODO(), &linodego.ListOptions{})
+	vpcs, err := client.ListVPCs(ctx, &linodego.ListOptions{})
 	if err != nil {
 		return 0, err
 	}
@@ -55,3 +57,22 @@ func GetVPCID(client client.Client, vpcName string) (int, error) {
 	}
 	return 0, vpcLookupError{vpcName}
 }
+
+// GetVPCIPAddresses returns vpc ip's for given VPC label
+func GetVPCIPAddresses(ctx context.Context, client client.Client, vpcName string) ([]linodego.VPCIP, error) {
+	vpcID, err := GetVPCID(ctx, client, strings.TrimSpace(vpcName))
+	if err != nil {
+		return nil, err
+	}
+	resp, err := client.ListVPCIPAddresses(ctx, vpcID, linodego.NewListOptions(0, ""))
+	if err != nil {
+		if strings.Contains(err.Error(), "Not found") {
+			Mu.Lock()
+			defer Mu.Unlock()
+			klog.Errorf("vpc %s not found. Deleting entry from cache", vpcName)
+			delete(vpcIDs, vpcName)
+		}
+		return nil, err
+	}
+	return resp, nil
+}