Quadlet - translate dependencies on other quadlet units

Signed-off-by: Ygal Blum <[email protected]>

Author: ygalblum

cmd/quadlet/main.go

@@ -43,17 +43,6 @@ var (
 
 var (
 	void struct{}
-	// Key: Extension
-	// Value: Processing order for resource naming dependencies
-	supportedExtensions = map[string]int{
-		".container": 4,
-		".volume":    2,
-		".kube":      4,
-		".network":   2,
-		".image":     1,
-		".build":     3,
-		".pod":       5,
-	}
 )
 
 // We log directly to /dev/kmsg, because that is the only way to get information out
@@ -312,7 +301,7 @@ func getUserLevelFilter(resolvedUnitDirAdminUser string) func(string, bool) bool
 
 func isExtSupported(filename string) bool {
 	ext := filepath.Ext(filename)
-	_, ok := supportedExtensions[ext]
+	_, ok := quadlet.SupportedExtensions[ext]
 	return ok
 }
 
@@ -714,7 +703,7 @@ func process() bool {
 	sort.Slice(units, func(i, j int) bool {
 		getOrder := func(i int) int {
 			ext := filepath.Ext(units[i].Filename)
-			order, ok := supportedExtensions[ext]
+			order, ok := quadlet.SupportedExtensions[ext]
 			if !ok {
 				return 0
 			}

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

@@ -258,6 +258,22 @@ the `network-online.target` unit is active with `systemctl is-active network-onl
 This behavior can be disabled by adding `DefaultDependencies=false` in the `Quadlet` section.
 Note, the _systemd_ `[Unit]` section has an option with the same name but a different meaning.
 
+### Dependency between Quadlet units
+
+Quadlet will automatically translate dependencies, specified in the keys
+`Wants`, `Requires`, `Requisite`, `BindsTo`, `PartOf`, `Upholds`, `Conflicts`, `Before` and `After`
+of the `[Unit]` section, between different Quadlet units.
+
+For example the `fedora.container` unit below specifies a dependency on the `basic.container` unit.
+```
+[Unit]
+After=basic.container
+Requires=basic.container
+
+[Container]
+Image=registry.fedoraproject.org/fedora:41
+```
+
 ## Container units [Container]
 
 Container units are named with a `.container` extension and contain a `[Container]` section describing

pkg/systemd/quadlet/quadlet.go

@@ -196,9 +196,33 @@ type UnitInfo struct {
 }
 
 var (
+	// Key: Extension
+	// Value: Processing order for resource naming dependencies
+	SupportedExtensions = map[string]int{
+		".container": 4,
+		".volume":    2,
+		".kube":      4,
+		".network":   2,
+		".image":     1,
+		".build":     3,
+		".pod":       5,
+	}
+
 	URL            = regexp.Delayed(`^((https?)|(git)://)|(github\.com/).+$`)
 	validPortRange = regexp.Delayed(`\d+(-\d+)?(/udp|/tcp)?$`)
 
+	unitDependencyKeys = []string{
+		"Wants",
+		"Requires",
+		"Requisite",
+		"BindsTo",
+		"PartOf",
+		"Upholds",
+		"Conflicts",
+		"Before",
+		"After",
+	}
+
 	// Supported keys in "Container" group
 	supportedContainerKeys = map[string]bool{
 		KeyAddCapability:         true,
@@ -514,6 +538,10 @@ func ConvertContainer(container *parser.UnitFile, isUser bool, unitsInfoMap map[
 	service := container.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, warnings, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if container.Path != "" {
@@ -923,6 +951,10 @@ func ConvertNetwork(network *parser.UnitFile, name string, unitsInfoMap map[stri
 	service := network.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, warnings, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if network.Path != "" {
@@ -1034,6 +1066,10 @@ func ConvertVolume(volume *parser.UnitFile, name string, unitsInfoMap map[string
 	service := volume.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, warnings, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if volume.Path != "" {
@@ -1173,6 +1209,10 @@ func ConvertKube(kube *parser.UnitFile, unitsInfoMap map[string]*UnitInfo, isUse
 	service := kube.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if kube.Path != "" {
@@ -1318,6 +1358,10 @@ func ConvertImage(image *parser.UnitFile, unitsInfoMap map[string]*UnitInfo, isU
 	service := image.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if image.Path != "" {
@@ -1399,6 +1443,10 @@ func ConvertBuild(build *parser.UnitFile, unitsInfoMap map[string]*UnitInfo, isU
 	service := build.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, warnings, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	/* Rename old Build group to X-Build so that systemd ignores it */
@@ -1568,6 +1616,10 @@ func ConvertPod(podUnit *parser.UnitFile, name string, unitsInfoMap map[string]*
 	service := podUnit.Dup()
 	service.Filename = unitInfo.ServiceFileName()
 
+	if err := translateUnitDependencies(service, unitsInfoMap); err != nil {
+		return nil, err
+	}
+
 	addDefaultDependencies(service, isUser)
 
 	if podUnit.Path != "" {
@@ -2260,3 +2312,36 @@ func handleExecReload(quadletUnitFile, serviceUnitFile *parser.UnitFile, groupNa
 
 	return nil
 }
+
+func translateUnitDependencies(serviceUnitFile *parser.UnitFile, unitsInfoMap map[string]*UnitInfo) error {
+	for _, unitDependencyKey := range unitDependencyKeys {
+		deps := serviceUnitFile.LookupAllStrv(UnitGroup, unitDependencyKey)
+		if len(deps) == 0 {
+			continue
+		}
+		translatedDeps := make([]string, 0, len(deps))
+		translated := false
+		for _, dep := range deps {
+			var translatedDep string
+
+			ext := filepath.Ext(dep)
+			if _, ok := SupportedExtensions[ext]; ok {
+				unitInfo, ok := unitsInfoMap[dep]
+				if !ok {
+					return fmt.Errorf("unable to translate dependency for %s", dep)
+				}
+				translatedDep = unitInfo.ServiceFileName()
+				translated = true
+			} else {
+				translatedDep = dep
+			}
+			translatedDeps = append(translatedDeps, translatedDep)
+		}
+		if !translated {
+			continue
+		}
+		serviceUnitFile.Unset(UnitGroup, unitDependencyKey)
+		serviceUnitFile.Add(UnitGroup, unitDependencyKey, strings.Join(translatedDeps, " "))
+	}
+	return nil
+}

test/e2e/quadlet/dependent.build

@@ -0,0 +1,10 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Build]
+ImageTag=localhost/imagename
+SetWorkingDirectory=unit

test/e2e/quadlet/dependent.container

@@ -0,0 +1,9 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Container]
+Image=localhost/imagename

test/e2e/quadlet/dependent.error.container

@@ -0,0 +1,9 @@
+## assert-failed
+## assert-stderr-contains "unable to translate dependency for basic.container"
+
+[Unit]
+After=basic.container
+Requires=basic.container
+
+[Container]
+Image=localhost/imagename

test/e2e/quadlet/dependent.image

@@ -0,0 +1,9 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Image]
+Image=localhost/imagename

test/e2e/quadlet/dependent.kube

@@ -0,0 +1,9 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Kube]
+Yaml=deployment.yml

test/e2e/quadlet/dependent.network

@@ -0,0 +1,8 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Network]

test/e2e/quadlet/dependent.pod

@@ -0,0 +1,8 @@
+## assert-key-is "Unit" "Requires" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+## assert-key-is-regex "Unit" "After" "network-online.target|podman-user-wait-network-online.service" "basic-build.service basic.service basic-image.service basic.service basic-network.service basic-pod.service basic-volume.service"
+
+[Unit]
+After=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+Requires=basic.build basic.container basic.image basic.kube basic.network basic.pod basic.volume
+
+[Pod]