Add podman machine events

Signed-off-by: Jhon Honce <jhonce@redhat.com>

10 files changed, 162 insertions, 25 deletions

diff --git a/cmd/podman/machine/init.go b/cmd/podman/machine/init.go
index 4991c6aa3..733266b85 100644
--- a/cmd/podman/machine/init.go
+++ b/cmd/podman/machine/init.go
@@ -9,6 +9,7 @@ import (
 
 	"github.com/containers/common/pkg/completion"
 	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/events"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
@@ -145,11 +146,14 @@ func initMachine(cmd *cobra.Command, args []string) error {
 		// Finished = *,     err != nil  -  Exit with an error message
 		return err
 	}
+	newMachineEvent(events.Init, events.Event{Name: initOpts.Name})
 	fmt.Println("Machine init complete")
+
 	if now {
 		err = vm.Start(initOpts.Name, machine.StartOptions{})
 		if err == nil {
 			fmt.Printf("Machine %q started successfully\n", initOpts.Name)
+			newMachineEvent(events.Start, events.Event{Name: initOpts.Name})
 		}
 	} else {
 		extra := ""
diff --git a/cmd/podman/machine/inspect.go b/cmd/podman/machine/inspect.go
index 21e5074b7..0ddcec8b5 100644
--- a/cmd/podman/machine/inspect.go
+++ b/cmd/podman/machine/inspect.go
@@ -4,7 +4,6 @@
 package machine
 
 import (
-	"encoding/json"
 	"os"
 
 	"github.com/containers/podman/v4/cmd/podman/common"
diff --git a/cmd/podman/machine/list.go b/cmd/podman/machine/list.go
index c987bf71a..861feee07 100644
--- a/cmd/podman/machine/list.go
+++ b/cmd/podman/machine/list.go
@@ -4,7 +4,6 @@
 package machine
 
 import (
-	"encoding/json"
 	"os"
 	"sort"
 	"strconv"
diff --git a/cmd/podman/machine/machine.go b/cmd/podman/machine/machine.go
index d3775f022..4c566b11f 100644
--- a/cmd/podman/machine/machine.go
+++ b/cmd/podman/machine/machine.go
@@ -4,25 +4,39 @@
 package machine
 
 import (
+	"errors"
+	"net"
+	"os"
+	"path/filepath"
+	"regexp"
 	"strings"
+	"sync"
+	"time"
 
 	"github.com/containers/podman/v4/cmd/podman/registry"
 	"github.com/containers/podman/v4/cmd/podman/validate"
+	"github.com/containers/podman/v4/libpod/events"
 	"github.com/containers/podman/v4/pkg/machine"
+	"github.com/containers/podman/v4/pkg/util"
+	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 )
 
 var (
-	noOp = func(cmd *cobra.Command, args []string) error {
-		return nil
-	}
+	// Pull in configured json library
+	json = registry.JSONLibrary()
+
+	sockPaths     []string   // Paths to unix domain sockets for publishing
+	openEventSock sync.Once  // Singleton support for opening sockets as needed
+	sockets       []net.Conn // Opened sockets, if any
+
 	// Command: podman _machine_
 	machineCmd = &cobra.Command{
 		Use:                "machine",
 		Short:              "Manage a virtual machine",
 		Long:               "Manage a virtual machine. Virtual machines are used to run Podman.",
-		PersistentPreRunE:  noOp,
-		PersistentPostRunE: noOp,
+		PersistentPreRunE:  initMachineEvents,
+		PersistentPostRunE: closeMachineEvents,
 		RunE:               validate.SubCommandExists,
 	}
 )
@@ -64,3 +78,111 @@ func getMachines(toComplete string) ([]string, cobra.ShellCompDirective) {
 	}
 	return suggestions, cobra.ShellCompDirectiveNoFileComp
 }
+
+func initMachineEvents(cmd *cobra.Command, _ []string) error {
+	logrus.Debugf("Called machine %s.PersistentPreRunE(%s)", cmd.Name(), strings.Join(os.Args, " "))
+
+	sockPaths, err := resolveEventSock()
+	if err != nil {
+		return err
+	}
+
+	// No sockets found, so no need to publish events...
+	if len(sockPaths) == 0 {
+		return nil
+	}
+
+	for _, path := range sockPaths {
+		conn, err := (&net.Dialer{}).DialContext(registry.Context(), "unix", path)
+		if err != nil {
+			logrus.Warnf("Failed to open event socket %q: %v", path, err)
+			continue
+		}
+		logrus.Debugf("Machine event socket %q found", path)
+		sockets = append(sockets, conn)
+	}
+	return nil
+}
+
+func resolveEventSock() ([]string, error) {
+	// Used mostly for testing
+	if sock, found := os.LookupEnv("PODMAN_MACHINE_EVENTS_SOCK"); found {
+		return []string{sock}, nil
+	}
+
+	xdg, err := util.GetRuntimeDir()
+	if err != nil {
+		logrus.Warnf("Failed to get runtime dir, machine events will not be published: %s", err)
+		return nil, nil
+	}
+
+	re := regexp.MustCompile(`machine_events.*\.sock`)
+	sockPaths := make([]string, 0)
+	fn := func(path string, info os.DirEntry, err error) error {
+		switch {
+		case err != nil:
+			return err
+		case info.IsDir():
+			return nil
+		case info.Type() != os.ModeSocket:
+			return nil
+		case !re.MatchString(info.Name()):
+			return nil
+		}
+
+		logrus.Debugf("Machine events will be published on: %q", path)
+		sockPaths = append(sockPaths, path)
+		return nil
+	}
+
+	if err := filepath.WalkDir(filepath.Join(xdg, "podman"), fn); err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return sockPaths, nil
+}
+
+func newMachineEvent(status events.Status, event events.Event) {
+	openEventSock.Do(func() {
+		// No sockets where found, so no need to publish events...
+		if len(sockPaths) == 0 {
+			return
+		}
+
+		for _, path := range sockPaths {
+			conn, err := (&net.Dialer{}).DialContext(registry.Context(), "unix", path)
+			if err != nil {
+				logrus.Warnf("Failed to open event socket %q: %v", path, err)
+				continue
+			}
+			logrus.Debugf("Machine event socket %q found", path)
+			sockets = append(sockets, conn)
+		}
+	})
+
+	event.Status = status
+	event.Time = time.Now()
+	event.Type = events.Machine
+
+	payload, err := json.Marshal(event)
+	if err != nil {
+		logrus.Errorf("Unable to format machine event: %q", err)
+		return
+	}
+
+	for _, sock := range sockets {
+		if _, err := sock.Write(payload); err != nil {
+			logrus.Errorf("Unable to write machine event: %q", err)
+		}
+	}
+}
+
+func closeMachineEvents(cmd *cobra.Command, _ []string) error {
+	logrus.Debugf("Called machine %s.PersistentPostRunE(%s)", cmd.Name(), strings.Join(os.Args, " "))
+	for _, sock := range sockets {
+		_ = sock.Close()
+	}
+	return nil
+}
diff --git a/cmd/podman/machine/rm.go b/cmd/podman/machine/rm.go
index 617a70a76..e678eb629 100644
--- a/cmd/podman/machine/rm.go
+++ b/cmd/podman/machine/rm.go
@@ -10,6 +10,7 @@ import (
 	"strings"
 
 	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/events"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/spf13/cobra"
 )
@@ -50,7 +51,7 @@ func init() {
 	flags.BoolVar(&destroyOptions.SaveImage, imageFlagName, false, "Do not delete the image file")
 }
 
-func rm(cmd *cobra.Command, args []string) error {
+func rm(_ *cobra.Command, args []string) error {
 	var (
 		err error
 		vm  machine.VM
@@ -83,5 +84,10 @@ func rm(cmd *cobra.Command, args []string) error {
 			return nil
 		}
 	}
-	return remove()
+	err = remove()
+	if err != nil {
+		return err
+	}
+	newMachineEvent(events.Remove, events.Event{Name: vmName})
+	return nil
 }
diff --git a/cmd/podman/machine/start.go b/cmd/podman/machine/start.go
index 56acb09cb..2b0c8213d 100644
--- a/cmd/podman/machine/start.go
+++ b/cmd/podman/machine/start.go
@@ -7,6 +7,7 @@ import (
 	"fmt"
 
 	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/events"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
@@ -31,7 +32,7 @@ func init() {
 	})
 }
 
-func start(cmd *cobra.Command, args []string) error {
+func start(_ *cobra.Command, args []string) error {
 	var (
 		err error
 		vm  machine.VM
@@ -62,5 +63,6 @@ func start(cmd *cobra.Command, args []string) error {
 		return err
 	}
 	fmt.Printf("Machine %q started successfully\n", vmName)
+	newMachineEvent(events.Start, events.Event{Name: vmName})
 	return nil
 }
diff --git a/cmd/podman/machine/stop.go b/cmd/podman/machine/stop.go
index e6bf3cf2b..dcb124dd4 100644
--- a/cmd/podman/machine/stop.go
+++ b/cmd/podman/machine/stop.go
@@ -7,6 +7,7 @@ import (
 	"fmt"
 
 	"github.com/containers/podman/v4/cmd/podman/registry"
+	"github.com/containers/podman/v4/libpod/events"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/spf13/cobra"
 )
@@ -49,5 +50,6 @@ func stop(cmd *cobra.Command, args []string) error {
 		return err
 	}
 	fmt.Printf("Machine %q stopped successfully\n", vmName)
+	newMachineEvent(events.Stop, events.Event{Name: vmName})
 	return nil
 }
diff --git a/cmd/podman/main.go b/cmd/podman/main.go
index 8f580601e..929c8a757 100644
--- a/cmd/podman/main.go
+++ b/cmd/podman/main.go
@@ -18,6 +18,7 @@ import (
 	_ "github.com/containers/podman/v4/cmd/podman/secrets"
 	_ "github.com/containers/podman/v4/cmd/podman/system"
 	_ "github.com/containers/podman/v4/cmd/podman/system/connection"
+	"github.com/containers/podman/v4/cmd/podman/validate"
 	_ "github.com/containers/podman/v4/cmd/podman/volumes"
 	"github.com/containers/podman/v4/pkg/domain/entities"
 	"github.com/containers/podman/v4/pkg/rootless"
@@ -64,8 +65,8 @@ func parseCommands() *cobra.Command {
 				c.Command.Hidden = true
 
 				// overwrite persistent pre/post function to skip setup
-				c.Command.PersistentPostRunE = noop
-				c.Command.PersistentPreRunE = noop
+				c.Command.PersistentPostRunE = validate.NoOp
+				c.Command.PersistentPreRunE = validate.NoOp
 				addCommand(c)
 				continue
 			}
@@ -120,7 +121,3 @@ func addCommand(c registry.CliCommand) {
 	c.Command.SetUsageTemplate(usageTemplate)
 	c.Command.DisableFlagsInUseLine = true
 }
-
-func noop(cmd *cobra.Command, args []string) error {
-	return nil
-}
diff --git a/cmd/podman/system/connection.go b/cmd/podman/system/connection.go
index 5164de78c..5dbe50fc9 100644
--- a/cmd/podman/system/connection.go
+++ b/cmd/podman/system/connection.go
@@ -7,18 +7,15 @@ import (
 )
 
 var (
-	// Skip creating engines since this command will obtain connection information to said engines
-	noOp = func(cmd *cobra.Command, args []string) error {
-		return nil
-	}
-
+	// ConnectionCmd skips creating engines (PersistentPreRunE/PersistentPostRunE are No-Op's) since
+	// sub-commands will obtain connection information to said engines
 	ConnectionCmd = &cobra.Command{
 		Use:                "connection",
-		Short:              "Manage remote ssh destinations",
-		Long:               `Manage ssh destination information in podman configuration`,
-		PersistentPreRunE:  noOp,
+		Short:              "Manage remote API service destinations",
+		Long:               `Manage remote API service destination information in podman configuration`,
+		PersistentPreRunE:  validate.NoOp,
 		RunE:               validate.SubCommandExists,
-		PersistentPostRunE: noOp,
+		PersistentPostRunE: validate.NoOp,
 		TraverseChildren:   false,
 	}
 )
diff --git a/cmd/podman/validate/noop.go b/cmd/podman/validate/noop.go
new file mode 100644
index 000000000..2243ef5c4
--- /dev/null
+++ b/cmd/podman/validate/noop.go
@@ -0,0 +1,9 @@
+package validate
+
+import (
+	"github.com/spf13/cobra"
+)
+
+func NoOp(_ *cobra.Command, _ []string) error {
+	return nil
+}