Quadlet: Add support for the Mount key in .container files

Handle the Mount key
Reuse code from the handling of the Volume key
Add E2E Test
E2E Test - Add checker for KeyValue string
Update man page

Signed-off-by: Ygal Blum <ygal.blum@gmail.com>

docs/source/markdown/podman-systemd.unit.5.md

@@ -89,6 +89,7 @@ Valid options for `[Container]` are listed below:
 | Image=ubi8                       | Image specification - ubi8             |
 | Label="YXZ"                      | --label "XYZ"                          |
 | LogDriver=journald               | --log-driver journald                  |
+| Mount=type=bind,source=/path/on/host,destination=/path/in/container | --mount type=bind,source=/path/on/host,destination=/path/in/container |
 | Network=host                     | --net host                             |
 | NoNewPrivileges=true             | --security-opt no-new-privileges       |
 | Rootfs=/var/lib/rootfs           | --rootfs /var/lib/rootfs               |
@@ -217,6 +218,19 @@ Equivalent to the Podman `--log-driver` option.
 
 The default value is `passthrough`.
 
+### `Mount=`
+
+Attach a filesystem mount to the container.
+This is equivalent to the Podman `--mount` option, and
+generally has the form `type=TYPE,TYPE-SPECIFIC-OPTION[,...]`.
+
+As a special case, for `type=volume` if `source` ends with `.volume`, a Podman named volume called
+`systemd-$name` will be used as the source, and the generated systemd service will contain
+a dependency on the `$name-volume.service`. Such a volume can be automatically be lazily
+created by using a `$name.volume` quadlet file.
+
+This key can be listed multiple times.
+
 ### `Network=`
 
 Specify a custom network for the container. This has the same format as the `--network` option

pkg/systemd/quadlet/quadlet.go

@@ -51,6 +51,7 @@ const (
 	KeyImage                 = "Image"
 	KeyLabel                 = "Label"
 	KeyLogDriver             = "LogDriver"
+	KeyMount                 = "Mount"
 	KeyNetwork               = "Network"
 	KeyNetworkDisableDNS     = "DisableDNS"
 	KeyNetworkDriver         = "Driver"
@@ -106,6 +107,7 @@ var (
 		KeyImage:                 true,
 		KeyLabel:                 true,
 		KeyLogDriver:             true,
+		KeyMount:                 true,
 		KeyNetwork:               true,
 		KeyNoNewPrivileges:       true,
 		KeyNotify:                true,
@@ -464,21 +466,7 @@ func ConvertContainer(container *parser.UnitFile, isUser bool) (*parser.UnitFile
 		}
 
 		if source != "" {
-			if source[0] == '/' {
-				// Absolute path
-				service.Add(UnitGroup, "RequiresMountsFor", source)
-			} else if strings.HasSuffix(source, ".volume") {
-				// the podman volume name is systemd-$name
-				volumeName := replaceExtension(source, "", "systemd-", "")
-
-				// the systemd unit name is $name-volume.service
-				volumeServiceName := replaceExtension(source, ".service", "", "-volume")
-
-				source = volumeName
-
-				service.Add(UnitGroup, "Requires", volumeServiceName)
-				service.Add(UnitGroup, "After", volumeServiceName)
-			}
+			source = handleStorageSource(service, source)
 		}
 
 		podman.add("-v")
@@ -530,6 +518,34 @@ func ConvertContainer(container *parser.UnitFile, isUser bool) (*parser.UnitFile
 		podman.add("--secret", secret)
 	}
 
+	mounts := container.LookupAllArgs(ContainerGroup, KeyMount)
+	for _, mount := range mounts {
+		params := strings.Split(mount, ",")
+		paramsMap := make(map[string]string, len(params))
+		for _, param := range params {
+			kv := strings.Split(param, "=")
+			paramsMap[kv[0]] = kv[1]
+		}
+		if paramType, ok := paramsMap["type"]; ok {
+			if paramType == "volume" || paramType == "bind" {
+				if paramSource, ok := paramsMap["source"]; ok {
+					paramsMap["source"] = handleStorageSource(service, paramSource)
+				} else if paramSource, ok = paramsMap["src"]; ok {
+					paramsMap["src"] = handleStorageSource(service, paramSource)
+				}
+			}
+		}
+		paramsArray := make([]string, 0, len(params))
+		paramsArray = append(paramsArray, fmt.Sprintf("%s=%s", "type", paramsMap["type"]))
+		for k, v := range paramsMap {
+			if k != "type" {
+				paramsArray = append(paramsArray, fmt.Sprintf("%s=%s", k, v))
+			}
+		}
+		mountStr := strings.Join(paramsArray, ",")
+		podman.add("--mount", mountStr)
+	}
+
 	podmanArgs := container.LookupAllArgs(ContainerGroup, KeyPodmanArgs)
 	podman.add(podmanArgs...)
 
@@ -992,3 +1008,23 @@ func handleLogDriver(unitFile *parser.UnitFile, groupName string, podman *Podman
 	}
 	podman.add("--log-driver", logDriver)
 }
+
+func handleStorageSource(unitFile *parser.UnitFile, source string) string {
+	if source[0] == '/' {
+		// Absolute path
+		unitFile.Add(UnitGroup, "RequiresMountsFor", source)
+	} else if strings.HasSuffix(source, ".volume") {
+		// the podman volume name is systemd-$name
+		volumeName := replaceExtension(source, "", "systemd-", "")
+
+		// the systemd unit name is $name-volume.service
+		volumeServiceName := replaceExtension(source, ".service", "", "-volume")
+
+		source = volumeName
+
+		unitFile.Add(UnitGroup, "Requires", volumeServiceName)
+		unitFile.Add(UnitGroup, "After", volumeServiceName)
+	}
+
+	return source
+}

test/e2e/quadlet/mount.container

@@ -0,0 +1,20 @@
+[Container]
+Image=localhost/imagename
+## assert-podman-args-key-val "--mount" "," "type=bind,source=/path/on/host,destination=/path/in/container"
+Mount=type=bind,source=/path/on/host,destination=/path/in/container
+## assert-podman-args-key-val "--mount" "," "type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared"
+Mount=type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared
+## assert-podman-args-key-val "--mount" "," "type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared,U=true"
+Mount=type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared,U=true
+## assert-podman-args-key-val "--mount" "," "type=volume,source=vol1,destination=/path/in/container,ro=true"
+Mount=type=volume,source=vol1,destination=/path/in/container,ro=true
+## assert-podman-args-key-val "--mount" "," "type=volume,source=systemd-vol2,destination=/path/in/container,ro=true"
+## assert-key-is "Unit" "Requires" "vol2-volume.service"
+## assert-key-is "Unit" "After" "vol2-volume.service"
+Mount=type=volume,source=vol2.volume,destination=/path/in/container,ro=true
+## assert-podman-args-key-val "--mount" "," "type=tmpfs,tmpfs-size=512M,destination=/path/in/container"
+Mount=type=tmpfs,tmpfs-size=512M,destination=/path/in/container
+## assert-podman-args-key-val "--mount" "," "type=image,source=fedora,destination=/fedora-image,rw=true"
+Mount=type=image,source=fedora,destination=/fedora-image,rw=true
+## assert-podman-args-key-val "--mount" "," "type=devpts,destination=/dev/pts"
+Mount=type=devpts,destination=/dev/pts

test/e2e/quadlet_test.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"reflect"
 	"regexp"
 	"strings"
 
@@ -175,6 +176,44 @@ func (t *quadletTestcase) assertPodmanArgsRegex(args []string, unit *parser.Unit
 	return findSublistRegex(podmanArgs, args) != -1
 }
 
+func keyValueStringToMap(keyValueString, seperator string) map[string]string {
+	keyValMap := make(map[string]string)
+	keyVarList := strings.Split(keyValueString, seperator)
+	for _, param := range keyVarList {
+		kv := strings.Split(param, "=")
+		keyValMap[kv[0]] = kv[1]
+	}
+
+	return keyValMap
+}
+
+func (t *quadletTestcase) assertPodmanArgsKeyVal(args []string, unit *parser.UnitFile, key string) bool {
+	podmanArgs, _ := unit.LookupLastArgs("Service", key)
+
+	expectedKeyValMap := keyValueStringToMap(args[2], args[1])
+	argKeyLocation := 0
+	for {
+		subListLocation := findSublist(podmanArgs[argKeyLocation:], []string{args[0]})
+		if subListLocation == -1 {
+			break
+		}
+
+		argKeyLocation += subListLocation
+		actualKeyValMap := keyValueStringToMap(podmanArgs[argKeyLocation+1], args[1])
+		if reflect.DeepEqual(expectedKeyValMap, actualKeyValMap) {
+			return true
+		}
+
+		argKeyLocation += 2
+
+		if argKeyLocation > len(podmanArgs) {
+			break
+		}
+	}
+
+	return false
+}
+
 func (t *quadletTestcase) assertPodmanFinalArgs(args []string, unit *parser.UnitFile, key string) bool {
 	podmanArgs, _ := unit.LookupLastArgs("Service", key)
 	if len(podmanArgs) < len(args) {
@@ -199,6 +238,10 @@ func (t *quadletTestcase) assertStartPodmanArgsRegex(args []string, unit *parser
 	return t.assertPodmanArgsRegex(args, unit, "ExecStart")
 }
 
+func (t *quadletTestcase) assertStartPodmanArgsKeyVal(args []string, unit *parser.UnitFile) bool {
+	return t.assertPodmanArgsKeyVal(args, unit, "ExecStart")
+}
+
 func (t *quadletTestcase) assertStartPodmanFinalArgs(args []string, unit *parser.UnitFile) bool {
 	return t.assertPodmanFinalArgs(args, unit, "ExecStart")
 }
@@ -264,6 +307,8 @@ func (t *quadletTestcase) doAssert(check []string, unit *parser.UnitFile, sessio
 		ok = t.assertStartPodmanArgs(args, unit)
 	case "assert-podman-args-regex":
 		ok = t.assertStartPodmanArgsRegex(args, unit)
+	case "assert-podman-args-key-val":
+		ok = t.assertStartPodmanArgsKeyVal(args, unit)
 	case "assert-podman-final-args":
 		ok = t.assertStartPodmanFinalArgs(args, unit)
 	case "assert-podman-final-args-regex":
@@ -484,6 +529,7 @@ var _ = Describe("quadlet system generator", func() {
 		Entry("env-host-false.container", "env-host-false.container"),
 		Entry("secrets.container", "secrets.container"),
 		Entry("logdriver.container", "logdriver.container"),
+		Entry("mount.container", "mount.container"),
 
 		Entry("basic.volume", "basic.volume"),
 		Entry("label.volume", "label.volume"),