dm-operator/: support start a new dm cluster with dm-masters and dm-workers

examples/dm/README.md

@@ -47,8 +47,8 @@ watch kubectl -n <namespace> get pod
 Explore the DM master interface:
 
 ```bash
-> kubectl -n <namespace> port-forward svc/basic-dm-master 8261:8261
-> dmctl --master-addr 127.0.0.1:8261 list-member
+> kubectl exec -ti -n <namespace> <cluster_name>-dm-master-0 -- /bin/sh
+> ./dmctl --master-addr <cluster_name>-dm-master.<namespace>:8261 list-member
 ```
 
 ## Destroy

pkg/controller/dmcluster/dm_cluster_controller.go

@@ -257,7 +257,8 @@ func (dcc *Controller) sync(key string) error {
 	if err != nil {
 		klog.V(4).Infof("cluster version: %s is not semantic versioning compatible", dc.MasterVersion())
 	} else if clusterVersionLT2 {
-		return fmt.Errorf("dm-operator only supports to deploy dm-2.0")
+		klog.Errorf("dm version %s not supported, dm-operator only supports to deploy dm-2.0", dc.MasterVersion())
+		return nil
 	}
 
 	return dcc.syncDMCluster(dc.DeepCopy())

pkg/dmapi/master_control.go

@@ -19,14 +19,11 @@ import (
 	"net/http"
 	"sync"
 
-	"github.com/pingcap/tidb-operator/pkg/controller"
-
 	"github.com/pingcap/tidb-operator/pkg/pdapi"
-
 	"github.com/pingcap/tidb-operator/pkg/util"
-	"k8s.io/klog"
 
 	"k8s.io/client-go/kubernetes"
+	"k8s.io/klog"
 )
 
 // Namespace is a newtype of a string
@@ -84,7 +81,7 @@ func masterClientKey(scheme string, namespace Namespace, clusterName string) str
 
 // MasterClientURL builds the url of master client
 func MasterClientURL(namespace Namespace, clusterName string, scheme string) string {
-	return fmt.Sprintf("%s://%s.%s:8261", scheme, controller.DMMasterMemberName(clusterName), string(namespace))
+	return fmt.Sprintf("%s://%s-dm-master.%s:8261", scheme, clusterName, string(namespace))
 }
 
 // FakeMasterControl implements a fake version of MasterControlInterface.

pkg/manager/member/pd_member_manager.go

@@ -827,15 +827,6 @@ func clusterVersionGreaterThanOrEqualTo4(version string) (bool, error) {
 	return v.Major() >= 4, nil
 }
 
-func clusterVersionLessThan2(version string) (bool, error) {
-	v, err := semver.NewVersion(version)
-	if err != nil {
-		return true, err
-	}
-
-	return v.Major() < 2, nil
-}
-
 func (pmm *pdMemberManager) collectUnjoinedMembers(tc *v1alpha1.TidbCluster, set *apps.StatefulSet, pdStatus map[string]v1alpha1.PDMember) error {
 	podSelector, podSelectErr := metav1.LabelSelectorAsSelector(set.Spec.Selector)
 	if podSelectErr != nil {