Shared plugin: refactor kvstore and docker ops

* Create a new kvStore interface, and have etcd as one of
the implementations of the kvStore interface.
* Move docker host related operations to dockerops package

client_plugin/Makefile

@@ -106,7 +106,9 @@ COMMON_SRC = utils/log_formatter/log_formatter.go \
 VMDK_PLUGIN_SRC = vmdk_plugin/main.go vmdk_plugin/main_linux.go \
 	drivers/photon/photon_driver.go drivers/vmdk/vmdk_driver.go
 
-SHARED_PLUGIN_SRC = shared_plugin/main.go drivers/shared/shared_driver.go drivers/shared/etcdops.go
+SHARED_PLUGIN_SRC = shared_plugin/main.go drivers/shared/shared_driver.go \
+	drivers/shared/kvstore/kvstore.go drivers/shared/kvstore/etcdops/etcdops.go \
+	drivers/shared/dockerops/dockerops.go
 
 TEST_SRC = ../tests/utils/inputparams/testparams.go
 

client_plugin/drivers/shared/dockerops/dockerops.go

@@ -0,0 +1,154 @@
+// Copyright 2017 VMware, Inc. All Rights Reserved.
+//
+// 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.
+
+// Docker host related operations
+//
+// DockerOps struct holds the docker client based on a certain API version
+// and docker socket. All the operations which require a docker client should
+// be executed through this structure, including docker volume create/remove,
+// docker service start/stop, and docker information retrieve.
+
+package dockerops
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	log "github.com/Sirupsen/logrus"
+	dockerClient "github.com/docker/engine-api/client"
+	dockerTypes "github.com/docker/engine-api/types"
+	"github.com/docker/engine-api/types/swarm"
+)
+
+const (
+	// dockerAPIVersion: docker engine 1.24 and above support this api version
+	dockerAPIVersion = "v1.24"
+	// dockerUSocket: Unix socket on which Docker engine is listening
+	dockerUSocket = "unix:///var/run/docker.sock"
+)
+
+// DockerOps is the interface for docker host related operations
+type DockerOps struct {
+	Dockerd *dockerClient.Client
+}
+
+func NewDockerOps() *DockerOps {
+	var d *DockerOps
+
+	client, err := dockerClient.NewClient(dockerUSocket, dockerAPIVersion, nil, nil)
+	if err != nil {
+		log.WithFields(
+			log.Fields{"error": err},
+		).Error("Failed to create client for Docker ")
+		return nil
+	}
+
+	d = &DockerOps{
+		Dockerd: client,
+	}
+
+	return d
+}
+
+// GetSwarmInfo - returns the node ID and node IP address in swarm cluster
+// also returns if this node is a manager or not
+func (d *DockerOps) GetSwarmInfo() (nodeID string, addr string, isManager bool, err error) {
+	info, err := d.Dockerd.Info(context.Background())
+	if err != nil {
+		return
+	}
+
+	// if node is not in active swarm mode, return error
+	if info.Swarm.LocalNodeState != swarm.LocalNodeStateActive {
+		err = fmt.Errorf("Swarm node state is not active, local node state: %s",
+			string(info.Swarm.LocalNodeState))
+		return
+	}
+
+	// get the swarmID and IP address of current node
+	nodeID = info.Swarm.NodeID
+	addr = info.Swarm.NodeAddr
+	isManager = info.Swarm.ControlAvailable
+
+	return
+}
+
+// GetSwarmManagers - return all the managers according to local docker info
+func (d *DockerOps) GetSwarmManagers() ([]swarm.Peer, error) {
+	info, err := d.Dockerd.Info(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	return info.Swarm.RemoteManagers, nil
+}
+
+// IsSwarmLeader - check if nodeID is a swarm leader or not
+// this function can only be executed successfully on a swarm manager node
+func (d *DockerOps) IsSwarmLeader(nodeID string) (bool, error) {
+	node, _, err := d.Dockerd.NodeInspectWithRaw(context.Background(), nodeID)
+	if err != nil {
+		return false, err
+	}
+
+	return node.ManagerStatus.Leader, nil
+}
+
+// GetSwarmLeader - return the IP address of the swarm leader
+// this function can only be executed successfully on a swarm manager node
+func (d *DockerOps) GetSwarmLeader() (string, error) {
+	nodes, err := d.Dockerd.NodeList(context.Background(), dockerTypes.NodeListOptions{})
+	if err != nil {
+		return "", err
+	}
+
+	for _, n := range nodes {
+		if n.ManagerStatus != nil && n.ManagerStatus.Leader == true {
+			return n.ManagerStatus.Addr, nil
+		}
+	}
+
+	msg := fmt.Sprintf("Failed to get leader for swarm manager")
+	return "", errors.New(msg)
+}
+
+// VolumeCreate - create volume from docker host with specific volume driver
+func (d *DockerOps) VolumeCreate(volumeDriver string, volName string, options map[string]string) error {
+	dockerVolOptions := dockerTypes.VolumeCreateRequest{
+		Driver:     volumeDriver,
+		Name:       volName,
+		DriverOpts: options,
+	}
+
+	_, err := d.Dockerd.VolumeCreate(context.Background(), dockerVolOptions)
+
+	return err
+}
+
+// VolumeCreate - remove volume from docker host with specific volume driver
+func (d *DockerOps) VolumeRemove(volName string) error {
+	return d.Dockerd.VolumeRemove(context.Background(), volName)
+}
+
+// StartSMBServer - Start SMB server
+func (d *DockerOps) StartSMBServer(volName string) bool {
+	log.Errorf("startSMBServer to be implemented")
+	return true
+}
+
+// StopSMBServer - Stop SMB server
+func (d *DockerOps) StopSMBServer(volName string) bool {
+	log.Errorf("stopSMBServer to be implemented")
+	return true
+}