export adding id-specifier code to setContainerNameForTemplate

Signed-off-by: Boaz Shuster <boaz.shuster.github@gmail.com>

pkg/systemd/generate/containers.go

@@ -206,6 +206,46 @@ func containerServiceName(ctr *libpod.Container, options entities.GenerateSystem
 	return nameOrID, serviceName
 }
 
+// setContainerNameForTemplate updates startCommand to contain the name argument with
+// a value that includes the identify specifier.
+// In case startCommand doesn't contain that argument it's added after "run" and its
+// value will be set to info.ServiceName concated with the identify specifier %i.
+func setContainerNameForTemplate(startCommand []string, info *containerInfo) ([]string, error) {
+	// find the index of "--name" in the command slice
+	nameIx := -1
+	for argIx, arg := range startCommand {
+		if arg == "--name" {
+			nameIx = argIx + 1
+			break
+		}
+		if strings.HasPrefix(arg, "--name=") {
+			nameIx = argIx
+			break
+		}
+	}
+	switch {
+	case nameIx == -1:
+		// if not found, add --name argument in the command slice before the "run" argument.
+		// it's assumed that the command slice contains this argument.
+		runIx := -1
+		for argIx, arg := range startCommand {
+			if arg == "run" {
+				runIx = argIx
+				break
+			}
+		}
+		if runIx == -1 {
+			return startCommand, fmt.Errorf("\"run\" is missing in the command arguments")
+		}
+		startCommand = append(startCommand[:runIx+1], startCommand[runIx:]...)
+		startCommand[runIx+1] = fmt.Sprintf("--name=%s-%%i", info.ServiceName)
+	default:
+		// append the identity specifier (%i) to the end of the --name value
+		startCommand[nameIx] = fmt.Sprintf("%s-%%i", startCommand[nameIx])
+	}
+	return startCommand, nil
+}
+
 // executeContainerTemplate executes the container template on the specified
 // containerInfo.  Note that the containerInfo is also post processed and
 // completed, which allows for an easier unit testing.
@@ -392,32 +432,9 @@ func executeContainerTemplate(info *containerInfo, options entities.GenerateSyst
 		startCommand = escapeSystemdArguments(startCommand)
 		if options.TemplateUnitFile {
 			info.IdentifySpecifier = true
-			runIx := -1
-			nameIx := -1
-			// Add systemd identify specifier next to the name value
-			// to set a name to the container according to the parameters passed to systemd.
-			// In case no --name set for that container, use ServiceName specified
-			// in the containerInfo struct.
-			for argIx, arg := range startCommand {
-				if arg == "run" {
-					runIx = argIx
-					continue
-				}
-				if arg == "--name" {
-					nameIx = argIx + 1
-					break
-				}
-				if strings.HasPrefix(arg, "--name=") {
-					nameIx = argIx
-					break
-				}
-			}
-			if nameIx == -1 {
-				startCommand = append(startCommand[:runIx+1], startCommand[runIx:]...)
-				startCommand[runIx+1] = fmt.Sprintf("--name=%s-%%i", info.ServiceName)
-				fmt.Println(startCommand)
-			} else {
-				startCommand[nameIx] = fmt.Sprintf("%s-%%i", startCommand[nameIx])
+			startCommand, err = setContainerNameForTemplate(startCommand, info)
+			if err != nil {
+				return "", err
 			}
 		}
 		info.ExecStart = strings.Join(startCommand, " ")

pkg/systemd/generate/containers_test.go

@@ -1,6 +1,7 @@
 package generate
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/containers/podman/v3/pkg/domain/entities"
@@ -1036,3 +1037,48 @@ WantedBy=multi-user.target default.target
 		})
 	}
 }
+
+func TestSetContainerNameForTemplate(t *testing.T) {
+	tt := []struct {
+		name         string
+		startCommand []string
+		info         *containerInfo
+		expected     []string
+		err          error
+	}{
+		{
+			name:         "no name argument is set",
+			startCommand: []string{"/usr/bin/podman", "run", "busybox", "top"},
+			info:         &containerInfo{ServiceName: "container-122"},
+			expected:     []string{"/usr/bin/podman", "run", "--name=container-122-%i", "busybox", "top"},
+			err:          nil,
+		},
+		{
+			name:         "--name=value is used in arguments",
+			startCommand: []string{"/usr/bin/podman", "run", "--name=lovely_james", "busybox", "top"},
+			info:         &containerInfo{},
+			expected:     []string{"/usr/bin/podman", "run", "--name=lovely_james-%i", "busybox", "top"},
+			err:          nil,
+		},
+		{
+			name:         "--name value is used in arguments",
+			startCommand: []string{"/usr/bin/podman", "run", "--name", "lovely_james", "busybox", "top"},
+			info:         &containerInfo{},
+			expected:     []string{"/usr/bin/podman", "run", "--name", "lovely_james-%i", "busybox", "top"},
+			err:          nil,
+		},
+		{
+			name:         "--name value is used in arguments",
+			startCommand: []string{"/usr/bin/podman", "create", "busybox", "top"},
+			info:         &containerInfo{},
+			expected:     []string{"/usr/bin/podman", "create", "busybox", "top"},
+			err:          fmt.Errorf("\"run\" is missing in the command arguments"),
+		},
+	}
+
+	for _, te := range tt {
+		res, err := setContainerNameForTemplate(te.startCommand, te.info)
+		assert.Equal(t, te.err, err)
+		assert.Equal(t, te.expected, res)
+	}
+}