sidecar: add Node interface for listing volumes

Signed-off-by: Niels de Vos <ndevos@ibm.com>

Author: nixpanic

sidecar/internal/volume-condition/node/node.go

@@ -0,0 +1,105 @@
+/*
+Copyright 2025 The Kubernetes-CSI-Addons Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package node
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/klog/v2"
+
+	"github.com/csi-addons/kubernetes-csi-addons/sidecar/internal/volume-condition/volume"
+)
+
+// Node can handle requests for the local worker node.
+type Node interface {
+	// ListCSIVolumes returns a slice of CSI-volumes that are attached to the
+	// local worker node.
+	ListCSIVolumes(ctx context.Context) ([]volume.CSIVolume, error)
+}
+
+type node struct {
+	clientset *kubernetes.Clientset
+
+	// nodename is used to filter the attachments by node
+	nodename string
+}
+
+// assert that node implements the Node interface.
+var _ Node = &node{}
+
+// NewNode creates a new Node that represents the local worker node.
+func NewNode(ctx context.Context, clientset *kubernetes.Clientset, nodename string) (Node, error) {
+	// verify that my local Node exists, will be fetched again in .ListCSIVolumes()
+	_, err := clientset.CoreV1().Nodes().Get(ctx, nodename, metav1.GetOptions{})
+	if err != nil {
+		return nil, fmt.Errorf("could not get my local Node %q: %v", nodename, err)
+	}
+
+	return &node{
+		clientset: clientset,
+		nodename:  nodename,
+	}, nil
+}
+
+func (n *node) ListCSIVolumes(ctx context.Context) ([]volume.CSIVolume, error) {
+	localNode, err := n.clientset.CoreV1().Nodes().Get(ctx, n.nodename, metav1.GetOptions{})
+	if err != nil {
+		return nil, fmt.Errorf("could not get Node %q: %v", n.nodename, err)
+	}
+
+	vols := []volume.CSIVolume{}
+	for _, attached := range localNode.Status.VolumesAttached {
+		var vol volume.CSIVolume
+		vol, err = newAttachedCSIVolume(attached.Name)
+		if err != nil {
+			klog.Infof("skipping non-CSI volume: %v", err)
+			continue
+		}
+
+		vols = append(vols, vol)
+	}
+
+	return vols, nil
+}
+
+// newAttachedCSIVolume parses a UniqueVolumeName that can be obtained from the list of attached
+// volumes on a node.
+// UniqueVolumeName is a string like "kubernetes.io/csi/ebs.csi.aws.com^vol-0c577c9c55718d592"
+// "vol-0c577c9c55718d592" is the volumeHandle (as in PV.Spec.CSI.volumeHandle)
+func newAttachedCSIVolume(name corev1.UniqueVolumeName) (volume.CSIVolume, error) {
+	const (
+		csiDriverPrefix       = "kubernetes.io/csi/"
+		driverVolumeSeparator = "^"
+	)
+
+	driverVolume, found := strings.CutPrefix(string(name), csiDriverPrefix)
+	if !found {
+		return nil, fmt.Errorf("attached volume %q is not a CSI volume", name)
+	}
+
+	parts := strings.Split(driverVolume, driverVolumeSeparator)
+	if len(parts) != 2 {
+		return nil, fmt.Errorf("format of attached volume %q is not supported: %s", name, driverVolume)
+	}
+
+	return volume.NewCSIVolume(parts[0], parts[1]), nil
+}

sidecar/internal/volume-condition/node/node_test.go

@@ -0,0 +1,78 @@
+/*
+Copyright 2025 The Kubernetes-CSI-Addons Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package node
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	corev1 "k8s.io/api/core/v1"
+)
+
+func TestNewAttachedCSIVolume(t *testing.T) {
+	cases := []struct {
+		name        string
+		volumeName  corev1.UniqueVolumeName
+		csiDriver   string // CSIVolume.GetDriver()
+		csiVolume   string // CSIVolume.GetVolumeID()
+		expectError bool
+	}{
+		{
+			name:        "happy path",
+			volumeName:  "kubernetes.io/csi/ebs.csi.aws.com^vol-0c577c9c55718d592",
+			csiDriver:   "ebs.csi.aws.com",
+			csiVolume:   "vol-0c577c9c55718d592",
+			expectError: false,
+		},
+		{
+			name:        "not a csi driver",
+			volumeName:  corev1.UniqueVolumeName("kubernetes.io/native/ebs.csi.aws.com^vol-0c577c9c55718d592"),
+			csiDriver:   "ebs.csi.aws.com",
+			csiVolume:   "vol-0c577c9c55718d592",
+			expectError: true,
+		},
+		{
+			name:        "repeated path component separator",
+			volumeName:  corev1.UniqueVolumeName("kubernetes.io/csi^ebs.csi.aws.com^vol-0c577c9c55718d592"),
+			csiDriver:   "ebs.csi.aws.com",
+			csiVolume:   "vol-0c577c9c55718d592",
+			expectError: true,
+		},
+		{
+			name:        "incorrect UniqueVolumeName format",
+			volumeName:  corev1.UniqueVolumeName("kubernetes.io/csi/ebs.csi.aws.com~vol-0c577c9c55718d592"),
+			csiDriver:   "ebs.csi.aws.com",
+			csiVolume:   "vol-0c577c9c55718d592",
+			expectError: true,
+		},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			volume, err := newAttachedCSIVolume(tt.volumeName)
+			if tt.expectError {
+				assert.NotNil(t, err)
+				return
+			} else {
+				assert.Nil(t, err)
+			}
+
+			assert.Equal(t, tt.csiDriver, volume.GetDriver())
+			assert.Equal(t, tt.csiVolume, volume.GetVolumeID())
+		})
+	}
+}