feat(occm): support multi region cluster

Currently, it supports only single auth section.
Set the regions in config as:

[Global]
region=REGION1
regions=REGION1
regions=REGION2
regions=REGION3

Author: sergelogvinov

docs/openstack-cloud-controller-manager/using-openstack-cloud-controller-manager.md

@@ -114,6 +114,8 @@ The options in `Global` section are used for openstack-cloud-controller-manager
   Keystone user password. If you are using [Keystone application credential](https://docs.openstack.org/keystone/latest/user/application_credentials.html), this option is not required.
 * `region`
   Required. Keystone region name.
+* `regions`
+  Optional. Keystone region name, which is used to specify regions for the cloud provider where the instance is running. Region is default region name. Can be specified multiple times.
 * `domain-id`
   Keystone user domain ID. If you are using [Keystone application credential](https://docs.openstack.org/keystone/latest/user/application_credentials.html), this option is not required.
 * `domain-name`
@@ -317,7 +319,7 @@ Although the openstack-cloud-controller-manager was initially implemented with N
   call](https://docs.openstack.org/api-ref/load-balancer/v2/?expanded=create-a-load-balancer-detail#creating-a-fully-populated-load-balancer).
   Setting this option to true will create loadbalancers using serial API calls which first create an unpopulated
   loadbalancer, then populate its listeners, pools and members. This is a compatibility option at the expense of
-  increased load on the OpenStack API. Default: false 
+  increased load on the OpenStack API. Default: false
 
 NOTE:
 

pkg/client/client.go

@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"net/http"
 	"runtime"
+	"slices"
 	"strings"
 
 	"github.com/gophercloud/gophercloud/v2"
@@ -53,6 +54,7 @@ type AuthOpts struct {
 	UserDomainID     string                   `gcfg:"user-domain-id" mapstructure:"user-domain-id" name:"os-userDomainID" value:"optional"`
 	UserDomainName   string                   `gcfg:"user-domain-name" mapstructure:"user-domain-name" name:"os-userDomainName" value:"optional"`
 	Region           string                   `name:"os-region"`
+	Regions          []string                 `name:"os-regions" value:"optional"`
 	EndpointType     gophercloud.Availability `gcfg:"os-endpoint-type" mapstructure:"os-endpoint-type" name:"os-endpointType" value:"optional"`
 	CAFile           string                   `gcfg:"ca-file" mapstructure:"ca-file" name:"os-certAuthorityPath" value:"optional"`
 	TLSInsecure      string                   `gcfg:"tls-insecure" mapstructure:"tls-insecure" name:"os-TLSInsecure" value:"optional" matches:"^true|false$"`
@@ -87,6 +89,7 @@ func LogCfg(authOpts AuthOpts) {
 	klog.V(5).Infof("UserDomainID: %s", authOpts.UserDomainID)
 	klog.V(5).Infof("UserDomainName: %s", authOpts.UserDomainName)
 	klog.V(5).Infof("Region: %s", authOpts.Region)
+	klog.V(5).Infof("Regions: %s", authOpts.Regions)
 	klog.V(5).Infof("EndpointType: %s", authOpts.EndpointType)
 	klog.V(5).Infof("CAFile: %s", authOpts.CAFile)
 	klog.V(5).Infof("CertFile: %s", authOpts.CertFile)
@@ -232,6 +235,20 @@ func ReadClouds(authOpts *AuthOpts) error {
 	authOpts.ApplicationCredentialName = replaceEmpty(authOpts.ApplicationCredentialName, cloud.AuthInfo.ApplicationCredentialName)
 	authOpts.ApplicationCredentialSecret = replaceEmpty(authOpts.ApplicationCredentialSecret, cloud.AuthInfo.ApplicationCredentialSecret)
 
+	regions := strings.Split(authOpts.Region, ",")
+	if len(regions) > 1 {
+		authOpts.Region = regions[0]
+	}
+
+	for _, r := range cloud.Regions {
+		// Support only single auth section in clouds.yaml
+		if r.Values.AuthInfo == nil && r.Name != authOpts.Region && !slices.Contains(regions, r.Name) {
+			regions = append(regions, r.Name)
+		}
+	}
+
+	authOpts.Regions = regions
+
 	return nil
 }
 

pkg/csi/cinder/openstack/openstack.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"net/http"
 	"os"
+	"slices"
 
 	"github.com/gophercloud/gophercloud/v2"
 	"github.com/gophercloud/gophercloud/v2/openstack"
@@ -126,7 +127,7 @@ func GetConfigFromFiles(configFilePaths []string) (Config, error) {
 		}
 	}
 
-	for _, global := range cfg.Global {
+	for idx, global := range cfg.Global {
 		// Update the config with data from clouds.yaml if UseClouds is enabled
 		if global.UseClouds {
 			if global.CloudsFile != "" {
@@ -138,6 +139,15 @@ func GetConfigFromFiles(configFilePaths []string) (Config, error) {
 			}
 			klog.V(5).Infof("Credentials are loaded from %s:", global.CloudsFile)
 		}
+
+		regions := []string{global.Region}
+		for _, region := range cfg.Global[idx].Regions {
+			if !slices.Contains(regions, region) {
+				regions = append(regions, region)
+			}
+		}
+
+		cfg.Global[idx].Regions = regions
 	}
 
 	return cfg, nil

pkg/csi/cinder/openstack/openstack_test.go

@@ -68,6 +68,7 @@ tenant-id=` + fakeTenantID + `
 domain-id=` + fakeDomainID + `
 ca-file=` + fakeCAfile + `
 region=` + fakeRegion + `
+regions=` + fakeRegion + `
 [Global "cloud2"]
 username=` + fakeUserName_cloud2 + `
 password=` + fakePassword_cloud2 + `
@@ -76,6 +77,8 @@ tenant-id=` + fakeTenantID_cloud2 + `
 domain-id=` + fakeDomainID_cloud2 + `
 ca-file=` + fakeCAfile_cloud2 + `
 region=` + fakeRegion_cloud2 + `
+regions=` + fakeRegion_cloud2 + `
+regions=` + fakeRegion_cloud2 + `
 [Global "cloud3"]
 username=` + fakeUserName_cloud3 + `
 password=` + fakePassword_cloud3 + `
@@ -112,6 +115,7 @@ rescan-on-resize=true`
 		CAFile:   fakeCAfile,
 		TenantID: fakeTenantID,
 		Region:   fakeRegion,
+		Regions:  []string{fakeRegion},
 	}
 	expectedOpts.Global["cloud2"] = &client.AuthOpts{
 		Username: fakeUserName_cloud2,
@@ -121,6 +125,7 @@ rescan-on-resize=true`
 		CAFile:   fakeCAfile_cloud2,
 		TenantID: fakeTenantID_cloud2,
 		Region:   fakeRegion_cloud2,
+		Regions:  []string{fakeRegion_cloud2},
 	}
 	expectedOpts.Global["cloud3"] = &client.AuthOpts{
 		Username: fakeUserName_cloud3,
@@ -130,6 +135,7 @@ rescan-on-resize=true`
 		CAFile:   fakeCAfile_cloud3,
 		TenantID: fakeTenantID_cloud3,
 		Region:   fakeRegion_cloud3,
+		Regions:  []string{fakeRegion_cloud3},
 	}
 
 	expectedOpts.BlockStorage.RescanOnResize = true
@@ -224,6 +230,7 @@ rescan-on-resize=true`
 		CAFile:       fakeCAfile,
 		TenantID:     fakeTenantID,
 		Region:       fakeRegion,
+		Regions:      []string{fakeRegion},
 		EndpointType: gophercloud.AvailabilityPublic,
 		UseClouds:    true,
 		CloudsFile:   wd + "/fixtures/clouds.yaml",
@@ -237,6 +244,7 @@ rescan-on-resize=true`
 		CAFile:       fakeCAfile_cloud2,
 		TenantID:     fakeTenantID_cloud2,
 		Region:       fakeRegion_cloud2,
+		Regions:      []string{fakeRegion_cloud2},
 		EndpointType: gophercloud.AvailabilityPublic,
 		UseClouds:    true,
 		CloudsFile:   wd + "/fixtures/clouds.yaml",
@@ -250,6 +258,7 @@ rescan-on-resize=true`
 		CAFile:       fakeCAfile_cloud3,
 		TenantID:     fakeTenantID_cloud3,
 		Region:       fakeRegion_cloud3,
+		Regions:      []string{fakeRegion_cloud3},
 		EndpointType: gophercloud.AvailabilityPublic,
 		UseClouds:    true,
 		CloudsFile:   wd + "/fixtures/clouds.yaml",