Make volumes-per-node limit configurable [CON-10973]

CHANGELOG.md

@@ -1,5 +1,8 @@
 ## unreleased
 
+* Make volumes-per-node limit configurable
+  [[GH-575]](https://github.com/digitalocean/csi-digitalocean/pull/575)
+
 ## v4.10.0 - 2024.06.05
 
 * Handle new max-volumes-per-node error message

cmd/do-csi-plugin/main.go

@@ -40,6 +40,7 @@ func main() {
 		defaultVolumesPageSize = flag.Uint("default-volumes-page-size", 0, "The default page size used when paging through volumes results (default: do not specify and let the DO API choose)")
 		doAPIRateLimitQPS      = flag.Float64("do-api-rate-limit", 0, "Impose QPS rate limit on DigitalOcean API usage (default: do not rate limit)")
 		validateAttachment     = flag.Bool("validate-attachment", false, "Validate if the attachment has fully completed before formatting/mounting the device")
+		volumeLimit            = flag.Uint("volume-limit", 7, "Volumes per node limit to report; needs to match limit imposed by DO storage backend (honored by Node service only)")
 		version                = flag.Bool("version", false, "Print the version and exit.")
 	)
 	flag.Parse()
@@ -64,6 +65,7 @@ func main() {
 		DefaultVolumesPageSize: *defaultVolumesPageSize,
 		DOAPIRateLimitQPS:      *doAPIRateLimitQPS,
 		ValidateAttachment:     *validateAttachment,
+		VolumeLimit:            *volumeLimit,
 	})
 	if err != nil {
 		log.Fatalln(err)

driver/driver.go

@@ -42,6 +42,8 @@ const (
 	// DefaultDriverName defines the name that is used in Kubernetes and the CSI
 	// system for the canonical, official name of this plugin
 	DefaultDriverName = "dobs.csi.digitalocean.com"
+
+	defaultMaxVolumesPerNode = 7
 )
 
 var (
@@ -86,8 +88,9 @@ type Driver struct {
 
 	// ready defines whether the driver is ready to function. This value will
 	// be used by the `Identity` service via the `Probe()` method.
-	readyMu sync.Mutex // protects ready
-	ready   bool
+	readyMu     sync.Mutex // protects ready
+	ready       bool
+	volumeLimit uint
 }
 
 // NewDriverParams defines the parameters that can be passed to NewDriver.
@@ -102,6 +105,7 @@ type NewDriverParams struct {
 	DefaultVolumesPageSize uint
 	DOAPIRateLimitQPS      float64
 	ValidateAttachment     bool
+	VolumeLimit            uint
 }
 
 // NewDriver returns a CSI plugin that contains the necessary gRPC
@@ -167,6 +171,7 @@ func NewDriver(p NewDriverParams) (*Driver, error) {
 		endpoint:               p.Endpoint,
 		debugAddr:              p.DebugAddr,
 		defaultVolumesPageSize: p.DefaultVolumesPageSize,
+		volumeLimit:            p.VolumeLimit,
 
 		hostID:  func() string { return hostID },
 		region:  region,
@@ -236,7 +241,7 @@ func (d *Driver) Run(ctx context.Context) error {
 			d.log.WithFields(logrus.Fields{
 				"limit":       details.limit,
 				"num_volumes": details.numVolumes,
-			}).Warn("CSI plugin will not function correctly, please resolve volume limit")
+			}).Warn("CSI plugin may not function correctly, please resolve volume limit")
 		}
 
 		if d.debugAddr != "" {

driver/driver_test.go

@@ -311,7 +311,7 @@ func (f *fakeStorageActionsDriver) Attach(ctx context.Context, volumeID string,
 		return nil, resp, errors.New("droplet was not found")
 	}
 
-	if len(droplet.VolumeIDs) >= maxVolumesPerNode {
+	if len(droplet.VolumeIDs) >= defaultMaxVolumesPerNode {
 		resp.Response = &http.Response{
 			StatusCode: http.StatusUnprocessableEntity,
 		}