engine: resources: cron: Add auto edges from SvcRes

engine/resources/cron.go

@@ -21,7 +21,8 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"os"
+	"os/user"
+	"path"
 	"strings"
 	"time"
 
@@ -141,15 +142,13 @@ func (obj *CronRes) Default() engine.Res {
 // validate and initialize the nested file resource and to apply the file state
 // in CheckApply.
 func (obj *CronRes) makeComposite() (*FileRes, error) {
-	// root timer
-	path := fmt.Sprintf("/etc/systemd/system/%s.timer", obj.Name())
-	if obj.Session {
-		// user timer
-		path = fmt.Sprintf("%s/.config/systemd/user/%s.timer", os.Getenv("HOME"), obj.Name())
-	}
-	res, err := engine.NewNamedResource("file", path)
+	p, err := obj.UnitFilePath()
 	if err != nil {
-		return nil, err
+		return nil, errwrap.Wrapf(err, "error generating unit file path")
+	}
+	res, err := engine.NewNamedResource("file", p)
+	if err != nil {
+		return nil, errwrap.Wrapf(err, "error creating nested file resource")
 	}
 	file, ok := res.(*FileRes)
 	if !ok {
@@ -260,14 +259,12 @@ func (obj *CronRes) Watch() error {
 	bus.Signal(dbusChan)
 	defer bus.RemoveSignal(dbusChan) // not needed here, but nice for symmetry
 
-	// root timer
-	path := fmt.Sprintf("/etc/systemd/system/%s.timer", obj.Name())
-	if obj.Session {
-		// user timer
-		path = fmt.Sprintf("%s/.config/systemd/user/%s.timer", os.Getenv("HOME"), obj.Name())
+	p, err := obj.UnitFilePath()
+	if err != nil {
+		return errwrap.Wrapf(err, "error generating unit file path")
 	}
 	// recwatcher for the systemd-timer unit file
-	obj.recWatcher, err = recwatch.NewRecWatcher(path, false)
+	obj.recWatcher, err = recwatch.NewRecWatcher(p, false)
 	if err != nil {
 		return err
 	}
@@ -453,7 +450,8 @@ type CronUID struct {
 	// used in the IFF function, is what you see in the struct fields here.
 	engine.BaseUID
 
-	name string // the machine name
+	unit    string // name of target unit
+	session bool   // user session
 }
 
 // IFF aka if and only if they are equivalent, return true. If not, false.
@@ -462,17 +460,38 @@ func (obj *CronUID) IFF(uid engine.ResUID) bool {
 	if !ok {
 		return false
 	}
-	return obj.name == res.name
+	if obj.unit != res.unit {
+		return false
+	}
+	if obj.session != res.session {
+		return false
+	}
+	return true
+}
+
+// AutoEdges returns the AutoEdge interface.
+func (obj *CronRes) AutoEdges() (engine.AutoEdge, error) {
+	return nil, nil
 }
 
 // UIDs includes all params to make a unique identification of this object.
 // Most resources only return one although some resources can return multiple.
 func (obj *CronRes) UIDs() []engine.ResUID {
-	x := &CronUID{
-		BaseUID: engine.BaseUID{Name: obj.Name(), Kind: obj.Kind()},
-		name:    obj.Name(), // svc name
+	unit := fmt.Sprintf("%s.service", obj.Name())
+	if obj.Unit != "" {
+		unit = obj.Unit
 	}
-	return append([]engine.ResUID{x}, obj.file.UIDs()...)
+	uids := []engine.ResUID{
+		&CronUID{
+			BaseUID: engine.BaseUID{Name: obj.Name(), Kind: obj.Kind()},
+			unit:    unit,        // name of target unit
+			session: obj.Session, // user session
+		},
+	}
+	if file, err := obj.makeComposite(); err == nil {
+		uids = append(uids, file.UIDs()...) // add the file uid if we can
+	}
+	return uids
 }
 
 // UnmarshalYAML is the custom unmarshal handler for this struct.
@@ -495,6 +514,23 @@ func (obj *CronRes) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	return nil
 }
 
+// UnitFilePath returns the path to the systemd-timer unit file.
+func (obj *CronRes) UnitFilePath() (string, error) {
+	// root timer
+	if !obj.Session {
+		return fmt.Sprintf("/etc/systemd/system/%s.timer", obj.Name()), nil
+	}
+	// user timer
+	u, err := user.Current()
+	if err != nil {
+		return "", errwrap.Wrapf(err, "error getting current user")
+	}
+	if u.HomeDir == "" {
+		return "", fmt.Errorf("user has no home directory")
+	}
+	return path.Join(u.HomeDir, "/.config/systemd/user/", fmt.Sprintf("%s.timer", obj.Name())), nil
+}
+
 // unitFileContents returns the contents of the unit file representing the
 // CronRes struct.
 func (obj *CronRes) unitFileContents() string {

engine/resources/svc.go

@@ -21,9 +21,12 @@ package resources
 
 import (
 	"fmt"
+	"os/user"
+	"path"
 
 	"github.com/purpleidea/mgmt/engine"
 	"github.com/purpleidea/mgmt/engine/traits"
+	engineUtil "github.com/purpleidea/mgmt/engine/util"
 	"github.com/purpleidea/mgmt/util"
 
 	systemd "github.com/coreos/go-systemd/dbus" // change namespace
@@ -381,6 +384,7 @@ type SvcUID struct {
 	// used in the IFF function, is what you see in the struct fields here.
 	engine.BaseUID
 	name    string // the svc name
+	session bool   // user session
 }
 
 // IFF aka if and only if they are equivalent, return true. If not, false.
@@ -389,7 +393,13 @@ func (obj *SvcUID) IFF(uid engine.ResUID) bool {
 	if !ok {
 		return false
 	}
-	return obj.name == res.name
+	if obj.name != res.name {
+		return false
+	}
+	if obj.session != res.session {
+		return false
+	}
+	return true
 }
 
 // SvcResAutoEdges holds the state of the auto edge generator.
@@ -431,13 +441,56 @@ func (obj *SvcResAutoEdges) Test(input []bool) bool {
 	return true // keep going
 }
 
-// AutoEdges returns the AutoEdge interface. In this case the systemd units.
+// SvcResAutoEdgesCron holds the state of the svc -> cron auto edge generator.
+type SvcResAutoEdgesCron struct {
+	unit    string // target unit
+	session bool   // user session
+}
+
+// Next returns the next automatic edge.
+func (obj *SvcResAutoEdgesCron) Next() []engine.ResUID {
+	// XXX: should this be true if SvcRes State == "stopped"?
+	reversed := false
+	value := &CronUID{
+		BaseUID: engine.BaseUID{
+			Kind:     "CronRes",
+			Reversed: &reversed,
+		},
+		unit:    obj.unit,    // target unit
+		session: obj.session, // user session
+	}
+	return []engine.ResUID{value} // we return one, even though api supports N
+}
+
+// Test takes the output of the last call to Next() and outputs true if we
+// should continue.
+func (obj *SvcResAutoEdgesCron) Test([]bool) bool {
+	return false // only get one svc -> cron edge
+}
+
+// AutoEdges returns the AutoEdge interface. In this case, systemd unit file
+// resources and cron (systemd-timer) resources.
 func (obj *SvcRes) AutoEdges() (engine.AutoEdge, error) {
 	var data []engine.ResUID
-	svcFiles := []string{
+	var svcFiles []string
+	svcFiles = []string{
+		// root svc
 		fmt.Sprintf("/etc/systemd/system/%s.service", obj.Name()),     // takes precedence
 		fmt.Sprintf("/usr/lib/systemd/system/%s.service", obj.Name()), // pkg default
 	}
+	if obj.Session {
+		// user svc
+		u, err := user.Current()
+		if err != nil {
+			return nil, errwrap.Wrapf(err, "error getting current user")
+		}
+		if u.HomeDir == "" {
+			return nil, fmt.Errorf("user has no home directory")
+		}
+		svcFiles = []string{
+			path.Join(u.HomeDir, "/.config/systemd/user/", fmt.Sprintf("%s.service", obj.Name())),
+		}
+	}
 	for _, x := range svcFiles {
 		var reversed = true
 		data = append(data, &FileUID{
@@ -449,11 +502,18 @@ func (obj *SvcRes) AutoEdges() (engine.AutoEdge, error) {
 			path: x, // what matters
 		})
 	}
-	return &FileResAutoEdges{
+
+	fileEdge := &FileResAutoEdges{
 		data:    data,
 		pointer: 0,
 		found:   false,
-	}, nil
+	}
+	cronEdge := &SvcResAutoEdgesCron{
+		session: obj.Session,
+		unit:    fmt.Sprintf("%s.service", obj.Name()),
+	}
+
+	return engineUtil.AutoEdgeCombiner(fileEdge, cronEdge)
 }
 
 // UIDs includes all params to make a unique identification of this object.
@@ -462,6 +522,7 @@ func (obj *SvcRes) UIDs() []engine.ResUID {
 	x := &SvcUID{
 		BaseUID: engine.BaseUID{Name: obj.Name(), Kind: obj.Kind()},
 		name:    obj.Name(),  // svc name
+		session: obj.Session, // user session
 	}
 	return []engine.ResUID{x}
 }

examples/lang/cron4.mcl

@@ -0,0 +1,17 @@
+$home = getenv("HOME")
+
+cron "purpleidea-oneshot" {
+    state => "absent",
+    session => true,
+    trigger => "OnCalendar",
+    time => "*:*:0",
+}
+
+svc "purpleidea-oneshot" {
+    state => "stopped",
+    session => true,
+}
+
+file printf("%s/.config/systemd/user/purpleidea-oneshot.service", $home) {
+    state => "absent",
+}