podman system prune support prune unused networks

This is an enhancement for the podman system prune feature.

In this issue, it is mentioned that 'network prune' should be
wired into 'podman system prune'
https://github.com/containers/podman/issues/8673

Therefore, I add the function to remove unused networks.

Signed-off-by: Toshiki Sonoda <sonoda.toshiki@fujitsu.com>

cmd/podman/system/prune.go

@@ -75,6 +75,7 @@ func prune(cmd *cobra.Command, args []string) error {
 		}
 	}
 
+	// Remove all unused pods, containers, images, networks, and volume data.
 	pruneOptions.Filters, err = parse.FilterArgumentsIntoFilters(filters)
 	if err != nil {
 		return err
@@ -106,6 +107,11 @@ func prune(cmd *cobra.Command, args []string) error {
 	if err != nil {
 		return err
 	}
+	// Print Network prune results
+	err = utils.PrintNetworkPruneResults(response.NetworkPruneReports, true)
+	if err != nil {
+		return err
+	}
 
 	fmt.Printf("Total reclaimed space: %s\n", units.HumanSize((float64)(response.ReclaimedSpace)))
 	return nil

cmd/podman/utils/utils.go

@@ -84,3 +84,18 @@ func PrintImagePruneResults(imagePruneReports []*reports.PruneReport, heading bo
 
 	return nil
 }
+
+func PrintNetworkPruneResults(networkPruneReport []*reports.PruneReport, heading bool) error {
+	var errs OutputErrors
+	if heading && len(networkPruneReport) > 0 {
+		fmt.Println("Deleted Networks")
+	}
+	for _, r := range networkPruneReport {
+		if r.Err == nil {
+			fmt.Println(r.Id)
+		} else {
+			errs = append(errs, r.Err)
+		}
+	}
+	return errs.PrintErrors()
+}

docs/source/markdown/podman-system-prune.1.md

@@ -1,13 +1,13 @@
 % podman-system-prune(1)
 
 ## NAME
-podman\-system\-prune - Remove all unused pod, container, image and volume data
+podman\-system\-prune - Remove all unused pods, containers, images, networks, and volume data
 
 ## SYNOPSIS
 **podman system prune** [*options*]
 
 ## DESCRIPTION
-**podman system prune** removes all unused containers (both dangling and unreferenced), pods and optionally, volumes from local storage.
+**podman system prune** removes all unused containers (both dangling and unreferenced), pods, networks, and optionally, volumes from local storage.
 
 With the **--all** option, you can delete all unused images.  Unused images are dangling images as well as any image that does not have any containers based on it.
 
@@ -16,7 +16,7 @@ By default, volumes are not removed to prevent important data from being deleted
 ## OPTIONS
 #### **--all**, **-a**
 
-Recursively remove all unused pod, container, image and volume data (Maximum 50 iterations.)
+Recursively remove all unused pods, containers, images, networks, and volume data. (Maximum 50 iterations.)
 
 #### **--filter**=*filters*
 

docs/source/markdown/podman-system.1.md

@@ -11,16 +11,16 @@ The system command allows you to manage the podman systems
 
 ## COMMANDS
 
-| Command    | Man Page                                                     | Description                                                          |
+| Command    | Man Page                                                     | Description                                                              |
-| -------    | ------------------------------------------------------------ | -------------------------------------------------------------------- |
+| -------    | ------------------------------------------------------------ | ------------------------------------------------------------------------ |
-| connection | [podman-system-connection(1)](podman-system-connection.1.md) | Manage the destination(s) for Podman service(s)                      |
+| connection | [podman-system-connection(1)](podman-system-connection.1.md) | Manage the destination(s) for Podman service(s)                          |
-| df         | [podman-system-df(1)](podman-system-df.1.md)                 | Show podman disk usage.                                              |
+| df         | [podman-system-df(1)](podman-system-df.1.md)                 | Show podman disk usage.                                                  |
-| info       | [podman-system-info(1)](podman-info.1.md)                    | Displays Podman related system information.                          |
+| info       | [podman-system-info(1)](podman-info.1.md)                    | Displays Podman related system information.                              |
-| migrate    | [podman-system-migrate(1)](podman-system-migrate.1.md)       | Migrate existing containers to a new podman version.                 |
+| migrate    | [podman-system-migrate(1)](podman-system-migrate.1.md)       | Migrate existing containers to a new podman version.                     |
-| prune      | [podman-system-prune(1)](podman-system-prune.1.md)           | Remove all unused pod, container, image and volume data.             |
+| prune      | [podman-system-prune(1)](podman-system-prune.1.md)           | Remove all unused pods, containers, images, networks, and volume data.   |
-| renumber   | [podman-system-renumber(1)](podman-system-renumber.1.md)     | Migrate lock numbers to handle a change in maximum number of locks.  |
+| renumber   | [podman-system-renumber(1)](podman-system-renumber.1.md)     | Migrate lock numbers to handle a change in maximum number of locks.      |
-| reset      | [podman-system-reset(1)](podman-system-reset.1.md)           | Reset storage back to initial state.                                 |
+| reset      | [podman-system-reset(1)](podman-system-reset.1.md)           | Reset storage back to initial state.                                     |
-| service    | [podman-system-service(1)](podman-system-service.1.md)       | Run an API service                                                   |
+| service    | [podman-system-service(1)](podman-system-service.1.md)       | Run an API service                                                       |
 
 ## SEE ALSO
 **[podman(1)](podman.1.md)**

pkg/domain/entities/system.go

@@ -28,6 +28,7 @@ type SystemPruneReport struct {
 	PodPruneReport        []*PodPruneReport
 	ContainerPruneReports []*reports.PruneReport
 	ImagePruneReports     []*reports.PruneReport
+	NetworkPruneReports   []*reports.PruneReport
 	VolumePruneReports    []*reports.PruneReport
 	ReclaimedSpace        uint64
 }

pkg/domain/infra/abi/network.go

@@ -142,7 +142,7 @@ func (ic *ContainerEngine) NetworkExists(ctx context.Context, networkname string
 	}, nil
 }
 
-// Network prune removes unused cni networks
+// Network prune removes unused networks
 func (ic *ContainerEngine) NetworkPrune(ctx context.Context, options entities.NetworkPruneOptions) ([]*entities.NetworkPruneReport, error) {
 	cons, err := ic.Libpod.GetAllContainers()
 	if err != nil {

pkg/domain/infra/abi/system.go

@@ -137,7 +137,7 @@ func (ic *ContainerEngine) SetupRootless(_ context.Context, noMoveProcess bool)
 	return nil
 }
 
-// SystemPrune removes unused data from the system. Pruning pods, containers, volumes and images.
+// SystemPrune removes unused data from the system. Pruning pods, containers, networks, volumes and images.
 func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.SystemPruneOptions) (*entities.SystemPruneReport, error) {
 	var systemPruneReport = new(entities.SystemPruneReport)
 	filters := []string{}
@@ -148,6 +148,9 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 	found := true
 	for found {
 		found = false
+
+		// TODO: Figure out cleaner way to handle all of the different PruneOptions
+		// Remove all unused pods.
 		podPruneReport, err := ic.prunePodHelper(ctx)
 		if err != nil {
 			return nil, err
@@ -155,9 +158,10 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 		if len(podPruneReport) > 0 {
 			found = true
 		}
+
 		systemPruneReport.PodPruneReport = append(systemPruneReport.PodPruneReport, podPruneReport...)
 
-		// TODO: Figure out cleaner way to handle all of the different PruneOptions
+		// Remove all unused containers.
 		containerPruneOptions := entities.ContainerPruneOptions{}
 		containerPruneOptions.Filters = (url.Values)(options.Filters)
 
@@ -165,16 +169,18 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 		if err != nil {
 			return nil, err
 		}
+
 		reclaimedSpace += reports.PruneReportsSize(containerPruneReports)
 		systemPruneReport.ContainerPruneReports = append(systemPruneReport.ContainerPruneReports, containerPruneReports...)
+
+		// Remove all unused images.
 		imagePruneOptions := entities.ImagePruneOptions{
 			All:    options.All,
 			Filter: filters,
 		}
+
 		imageEngine := ImageEngine{Libpod: ic.Libpod}
 		imagePruneReports, err := imageEngine.Prune(ctx, imagePruneOptions)
-		reclaimedSpace += reports.PruneReportsSize(imagePruneReports)
-
 		if err != nil {
 			return nil, err
 		}
@@ -182,10 +188,33 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 			found = true
 		}
 
+		reclaimedSpace += reports.PruneReportsSize(imagePruneReports)
 		systemPruneReport.ImagePruneReports = append(systemPruneReport.ImagePruneReports, imagePruneReports...)
+
+		// Remove all unused networks.
+		networkPruneOptions := entities.NetworkPruneOptions{}
+		networkPruneOptions.Filters = options.Filters
+
+		networkPruneReport, err := ic.NetworkPrune(ctx, networkPruneOptions)
+		if err != nil {
+			return nil, err
+		}
+		if len(networkPruneReport) > 0 {
+			found = true
+		}
+		for _, net := range networkPruneReport {
+			systemPruneReport.NetworkPruneReports = append(systemPruneReport.NetworkPruneReports, &reports.PruneReport{
+				Id:   net.Name,
+				Err:  net.Error,
+				Size: 0,
+			})
+		}
+
+		// Remove unused volume data.
 		if options.Volume {
 			volumePruneOptions := entities.VolumePruneOptions{}
 			volumePruneOptions.Filters = (url.Values)(options.Filters)
+
 			volumePruneReport, err := ic.VolumePrune(ctx, volumePruneOptions)
 			if err != nil {
 				return nil, err
@@ -193,6 +222,7 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 			if len(volumePruneReport) > 0 {
 				found = true
 			}
+
 			reclaimedSpace += reports.PruneReportsSize(volumePruneReport)
 			systemPruneReport.VolumePruneReports = append(systemPruneReport.VolumePruneReports, volumePruneReport...)
 		}

test/e2e/prune_test.go

@@ -258,6 +258,29 @@ var _ = Describe("Podman prune", func() {
 		Expect(pods.OutputToStringArray()).To(HaveLen(2))
 	})
 
+	It("podman system prune networks", func() {
+		// About netavark network backend test.
+		session := podmanTest.Podman([]string{"network", "create", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		session = podmanTest.Podman([]string{"system", "prune", "-f"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		// Default network should exists.
+		session = podmanTest.Podman([]string{"network", "ls", "-q", "--filter", "name=^podman$"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToStringArray()).To(HaveLen(1))
+
+		// Remove all unused networks.
+		session = podmanTest.Podman([]string{"network", "ls", "-q", "--filter", "name=^test$"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToStringArray()).To(HaveLen(0))
+	})
+
 	It("podman system prune - pod,container stopped", func() {
 		session := podmanTest.Podman([]string{"pod", "create"})
 		session.WaitWithDefaultTimeout()