Set random container name if not set

Signed-off-by: Christopher Crone <christopher.crone@docker.com>

cli/options/run/opts.go

@@ -5,6 +5,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/docker/docker/pkg/namesgenerator"
 	"github.com/docker/go-connections/nat"
 
 	"github.com/docker/api/containers"
@@ -20,6 +21,10 @@ type Opts struct {
 
 // ToContainerConfig convert run options to a container configuration
 func (r *Opts) ToContainerConfig(image string) (containers.ContainerConfig, error) {
+	if r.Name == "" {
+		r.Name = getRandomName()
+	}
+
 	publish, err := r.toPorts()
 	if err != nil {
 		return containers.ContainerConfig{}, err
@@ -83,3 +88,8 @@ func toLabels(labels []string) (map[string]string, error) {
 
 	return result, nil
 }
+
+func getRandomName() string {
+	// Azure supports hyphen but not underscore in names
+	return strings.Replace(namesgenerator.GetRandomName(0), "_", "-", -1)
+}

cli/options/run/opts_test.go

@@ -2,6 +2,7 @@ package run
 
 import (
 	"errors"
+	"regexp"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -15,6 +16,21 @@ type RunOptsSuite struct {
 	suite.Suite
 }
 
+var (
+	// AzureNameRegex is used to validate container names
+	// Regex was taken from server side error:
+	// The container name must contain no more than 63 characters and must match the regex '[a-z0-9]([-a-z0-9]*[a-z0-9])?' (e.g. 'my-name').
+	AzureNameRegex = regexp.MustCompile("[a-z0-9]([-a-z0-9]*[a-z0-9])")
+)
+
+// TestAzureRandomName ensures compliance with Azure naming requirements
+func (s *RunOptsSuite) TestAzureRandomName() {
+	n := getRandomName()
+	require.Less(s.T(), len(n), 64)
+	require.Greater(s.T(), len(n), 1)
+	require.Regexp(s.T(), AzureNameRegex, n)
+}
+
 func (s *RunOptsSuite) TestPortParse() {
 	testCases := []struct {
 		in       string