Changes for new version of esplora image (#62)

* changes for new version of esplora image

* add electrs port and esplora url env vars in compose yaml files

* wrap viper methods into Config type and use constants package

* add controller to interact with nigiri resources:
 * .env for docker-compose
 * docker daemon
 * json config file

* add use of constants and config packages and change start flag from --port to --env

* add package for global constants and variables

* add use of controller and constants packages instead of local methods and vars

* bump version

* use contants in logs command tests

cli/controller/docker.go

@@ -0,0 +1,101 @@
+package controller
+
+import (
+	"context"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/client"
+	"github.com/vulpemventures/nigiri/cli/constants"
+)
+
+// Docker type handles interfaction with containers via docker and docker-compose
+type Docker struct {
+	cli *client.Client
+}
+
+// New initialize a new Docker handler
+func (d *Docker) New() error {
+	cli, err := client.NewEnvClient()
+	if err != nil {
+		return err
+	}
+	d.cli = cli
+	return nil
+}
+
+func (d *Docker) isDockerRunning() bool {
+	_, err := d.cli.ContainerList(context.Background(), types.ContainerListOptions{All: false})
+	if err != nil {
+		return false
+	}
+	return true
+}
+
+func (d *Docker) findNigiriContainers(listAllContainers bool) bool {
+	containers, _ := d.cli.ContainerList(context.Background(), types.ContainerListOptions{All: listAllContainers})
+
+	if len(containers) <= 0 {
+		return false
+	}
+
+	images := []string{}
+	for _, c := range containers {
+		images = append(images, c.Image)
+	}
+
+	for _, nigiriImage := range constants.NigiriImages {
+		// just check if services for bitcoin chain are up and running
+		if !strings.Contains(nigiriImage, "liquid") {
+			if !contains(images, nigiriImage) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+func (d *Docker) isNigiriRunning() bool {
+	return d.findNigiriContainers(false)
+}
+
+func (d *Docker) isNigiriStopped() bool {
+	isRunning := d.isNigiriRunning()
+	if !isRunning {
+		return d.findNigiriContainers(true)
+	}
+	return false
+}
+
+func (d *Docker) cleanVolumes(path string) error {
+	subdirs, err := ioutil.ReadDir(path)
+	if err != nil {
+		return err
+	}
+
+	for _, d := range subdirs {
+		path := filepath.Join(path, d.Name())
+		subsubdirs, _ := ioutil.ReadDir(path)
+		for _, sd := range subsubdirs {
+			if sd.IsDir() {
+				if err := os.RemoveAll(filepath.Join(path, sd.Name())); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func contains(list []string, elem string) bool {
+	for _, l := range list {
+		if l == elem {
+			return true
+		}
+	}
+	return false
+}