From 2c5f950ac5f35c919d7088c41dcbdcf2be329dba Mon Sep 17 00:00:00 2001
From: prateekpandey14 <prateek.pandey@mayadata.io>
Date: Wed, 16 Dec 2020 23:22:04 +0530
Subject: [PATCH] feat(topology): add support for custom topology keys

Signed-off-by: prateekpandey14 <prateek.pandey@mayadata.io>
---
 pkg/driver/controller.go | 50 ++++++++++++++++++++++++++++++++--------
 pkg/driver/node.go       | 35 +++++++++++++++++++++++++++-
 2 files changed, 74 insertions(+), 11 deletions(-)

diff --git a/pkg/driver/controller.go b/pkg/driver/controller.go
index cb99468cd..08d448bb2 100644
--- a/pkg/driver/controller.go
+++ b/pkg/driver/controller.go
@@ -24,6 +24,7 @@ import (
 	"github.com/container-storage-interface/spec/lib/go/csi"
 	apisv1 "github.com/openebs/api/v2/pkg/apis/cstor/v1"
 	"github.com/openebs/cstor-csi/pkg/env"
+	k8snode "github.com/openebs/cstor-csi/pkg/kubernetes/node"
 	csipayload "github.com/openebs/cstor-csi/pkg/payload"
 	analytics "github.com/openebs/cstor-csi/pkg/usage"
 	utils "github.com/openebs/cstor-csi/pkg/utils"
@@ -33,6 +34,7 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	k8serror "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 // controller is the server implementation
@@ -106,7 +108,10 @@ func (cs *controller) CreateVolume(
 	pvcName := req.GetParameters()[pvcNameKey]
 	pvcNamespace := req.GetParameters()[pvcNamespaceKey]
 
-	nodeID = getAccessibilityRequirements(req.GetAccessibilityRequirements())
+	nodeID, err = getAccessibilityRequirements(req.GetAccessibilityRequirements())
+	if err != nil {
+		return nil, err
+	}
 
 	contentSource := req.GetVolumeContentSource()
 	if contentSource != nil && contentSource.GetSnapshot() != nil {
@@ -337,20 +342,20 @@ func (cs *controller) ListVolumes(
 	return nil, status.Error(codes.Unimplemented, "")
 }
 
-func getAccessibilityRequirements(requirement *csi.TopologyRequirement) string {
+func getAccessibilityRequirements(requirement *csi.TopologyRequirement) (string, error) {
 	if requirement == nil {
-		return ""
+		return "", status.Error(codes.Internal, "accessibility_requirements not found")
 	}
 
-	preferredNode, exists := requirement.GetPreferred()[0].GetSegments()[TopologyNodeKey]
-	if exists {
-		return preferredNode
+	node, err := getNode(requirement)
+	if err != nil {
+		return "", status.Errorf(codes.Internal, "failed to get the accessibility_requirements node %v", err)
 	}
-	preferredNode, exists = requirement.GetRequisite()[0].GetSegments()[TopologyNodeKey]
-	if exists {
-		return preferredNode
+
+	if len(node) == 0 {
+		return "", status.Error(codes.Internal, "can not find any node")
 	}
-	return ""
+	return node, nil
 }
 
 // sendEventOrIgnore sends anonymous cstor provision/delete events
@@ -366,3 +371,28 @@ func sendEventOrIgnore(pvcName, pvName, capacity, replicaCount, stgType, method
 			SetVolumeCapacity(capacity).Send()
 	}
 }
+
+// getNode gets the node which satisfies the topology info
+func getNode(topo *csi.TopologyRequirement) (string, error) {
+
+	list, err := k8snode.NewKubeClient().List(metav1.ListOptions{})
+	if err != nil {
+		return "", err
+	}
+
+	for _, prf := range topo.Preferred {
+		for _, node := range list.Items {
+			nodeFiltered := false
+			for key, value := range prf.Segments {
+				if node.Labels[key] != value {
+					nodeFiltered = true
+					break
+				}
+			}
+			if nodeFiltered == false {
+				return node.Name, nil
+			}
+		}
+	}
+	return "", nil
+}
diff --git a/pkg/driver/node.go b/pkg/driver/node.go
index 8d4cbf0d2..f157c56fd 100644
--- a/pkg/driver/node.go
+++ b/pkg/driver/node.go
@@ -25,12 +25,14 @@ import (
 	"github.com/container-storage-interface/spec/lib/go/csi"
 	apis "github.com/openebs/cstor-csi/pkg/apis/cstor/v1"
 	iscsiutils "github.com/openebs/cstor-csi/pkg/iscsi"
+	k8snode "github.com/openebs/cstor-csi/pkg/kubernetes/node"
 	utils "github.com/openebs/cstor-csi/pkg/utils"
 	"github.com/sirupsen/logrus"
 	"golang.org/x/net/context"
 	"golang.org/x/sys/unix"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 // node is the server implementation
@@ -64,8 +66,39 @@ func (ns *node) NodeGetInfo(
 	ctx context.Context,
 	req *csi.NodeGetInfoRequest,
 ) (*csi.NodeGetInfoResponse, error) {
+	node, err := k8snode.NewKubeClient().Get(ns.driver.config.NodeID, metav1.GetOptions{})
+	if err != nil {
+		logrus.Errorf("failed to get the node %s", ns.driver.config.NodeID)
+		return nil, err
+	}
+
+	/*
+	 * The driver will support all the keys and values defined in the node's label.
+	 * if nodes are labeled with the below keys and values
+	 * map[beta.kubernetes.io/arch:amd64 beta.kubernetes.io/os:linux
+	 * kubernetes.io/arch:amd64 kubernetes.io/hostname:storage-node-1
+	 * kubernetes.io/os:linux node-role.kubernetes.io/worker:true
+	 * openebs.io/zone:zone1 openebs.io/zpool:ssd]
+	 * The driver will support below key and values
+	 *
+	 * {
+	 *	beta.kubernetes.io/arch:amd64
+	 *	beta.kubernetes.io/os:linux
+	 *	kubernetes.io/arch:amd64
+	 *	kubernetes.io/hostname:storage-node-1
+	 *	kubernetes.io/os:linux
+	 *	node-role.kubernetes.io/worker:true
+	 *	openebs.io/zone:zone1
+	 *	openebs.io/zpool:ssd
+	 * }
+	 */
+
+	// support all the keys that node has
+	topology := node.Labels
+
+	// add driver's topology key
+	topology[TopologyNodeKey] = ns.driver.config.NodeID
 
-	topology := map[string]string{TopologyNodeKey: ns.driver.config.NodeID}
 	return &csi.NodeGetInfoResponse{
 		NodeId: ns.driver.config.NodeID,
 		AccessibleTopology: &csi.Topology{