dockerutil pkg to manage docker api client and context

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

util/dockerutil/context.go

@@ -0,0 +1,40 @@
+package dockerutil
+
+import (
+	"github.com/docker/cli/cli/command"
+	"github.com/docker/cli/cli/context/docker"
+	"github.com/pkg/errors"
+)
+
+// GetDockerEndpoint returns docker endpoint meta for given context
+func GetDockerEndpoint(dockerCli command.Cli, name string) (*docker.EndpointMeta, error) {
+	list, err := dockerCli.ContextStore().List()
+	if err != nil {
+		return nil, err
+	}
+	for _, l := range list {
+		if l.Name == name {
+			epm, err := docker.EndpointFromContext(l)
+			if err != nil {
+				return nil, err
+			}
+			return &epm, nil
+		}
+	}
+	return nil, nil
+}
+
+// GetCurrentEndpoint returns the current default endpoint value
+func GetCurrentEndpoint(dockerCli command.Cli) (string, error) {
+	name := dockerCli.CurrentContext()
+	if name != "default" {
+		return name, nil
+	}
+	dem, err := GetDockerEndpoint(dockerCli, name)
+	if err != nil {
+		return "", errors.Errorf("docker endpoint for %q not found", name)
+	} else if dem != nil {
+		return dem.Host, nil
+	}
+	return "", nil
+}