@@ -3,12 +3,15 @@ package build // import "github.com/docker/docker/api/server/backend/build"

 import (

 	"context"

 	"fmt"

+	"strconv"

 	"github.com/docker/distribution/reference"

 	"github.com/docker/docker/api/types"

 	"github.com/docker/docker/api/types/backend"

+	"github.com/docker/docker/api/types/events"

 	"github.com/docker/docker/builder"

 	buildkit "github.com/docker/docker/builder/builder-next"

+	daemonevents "github.com/docker/docker/daemon/events"

 	"github.com/docker/docker/image"

 	"github.com/docker/docker/pkg/stringid"

 	"github.com/pkg/errors"

@@ -31,11 +34,12 @@ type Backend struct {

 	builder        Builder

 	imageComponent ImageComponent

 	buildkit       *buildkit.Builder

+	eventsService  *daemonevents.Events

 }

 // NewBackend creates a new build backend from components

-func NewBackend(components ImageComponent, builder Builder, buildkit *buildkit.Builder) (*Backend, error) {

-	return &Backend{imageComponent: components, builder: builder, buildkit: buildkit}, nil

+func NewBackend(components ImageComponent, builder Builder, buildkit *buildkit.Builder, es *daemonevents.Events) (*Backend, error) {

+	return &Backend{imageComponent: components, builder: builder, buildkit: buildkit, eventsService: es}, nil

 }

 // RegisterGRPC registers buildkit controller to the grpc server.

@@ -100,6 +104,11 @@ func (b *Backend) PruneCache(ctx context.Context, opts types.BuildCachePruneOpti

 	if err != nil {

 		return nil, errors.Wrap(err, "failed to prune build cache")

 	}

+	b.eventsService.Log("prune", events.BuilderEventType, events.Actor{

+		Attributes: map[string]string{

+			"reclaimed": strconv.FormatInt(buildCacheSize, 10),

+		},

+	})

 	return &types.BuildCachePruneReport{SpaceReclaimed: uint64(buildCacheSize), CachesDeleted: cacheIDs}, nil

 }

@@ -8131,13 +8131,13 @@ paths:

         Various objects within Docker report events when something happens to them.

-        Containers report these events: `attach`, `commit`, `copy`, `create`, `destroy`, `detach`, `die`, `exec_create`, `exec_detach`, `exec_start`, `exec_die`, `export`, `health_status`, `kill`, `oom`, `pause`, `rename`, `resize`, `restart`, `start`, `stop`, `top`, `unpause`, and `update`

+        Containers report these events: `attach`, `commit`, `copy`, `create`, `destroy`, `detach`, `die`, `exec_create`, `exec_detach`, `exec_start`, `exec_die`, `export`, `health_status`, `kill`, `oom`, `pause`, `rename`, `resize`, `restart`, `start`, `stop`, `top`, `unpause`, `update`, and `prune`

-        Images report these events: `delete`, `import`, `load`, `pull`, `push`, `save`, `tag`, and `untag`

+        Images report these events: `delete`, `import`, `load`, `pull`, `push`, `save`, `tag`, `untag`, and `prune`

-        Volumes report these events: `create`, `mount`, `unmount`, and `destroy`

+        Volumes report these events: `create`, `mount`, `unmount`, `destroy`, and `prune`

-        Networks report these events: `create`, `connect`, `disconnect`, `destroy`, `update`, and `remove`

+        Networks report these events: `create`, `connect`, `disconnect`, `destroy`, `update`, `remove`, and `prune`

         The Docker daemon reports these events: `reload`

@@ -8149,6 +8149,8 @@ paths:

         Configs report these events: `create`, `update`, and `remove`

+        The Builder reports `prune` events

+

       operationId: "SystemEvents"

       produces:

         - "application/json"

@@ -1,6 +1,8 @@

 package events // import "github.com/docker/docker/api/types/events"

 const (

+	// BuilderEventType is the event type that the builder generates

+	BuilderEventType = "builder"

 	// ContainerEventType is the event type that containers generate

 	ContainerEventType = "container"

 	// DaemonEventType is the event type that daemon generate

@@ -299,7 +299,7 @@ func newRouterOptions(config *config.Config, d *daemon.Daemon) (routerOptions, e

 		return opts, err

 	}

-	bb, err := buildbackend.NewBackend(d.ImageService(), manager, bk)

+	bb, err := buildbackend.NewBackend(d.ImageService(), manager, bk, d.EventsService)

 	if err != nil {

 		return opts, errors.Wrap(err, "failed to create buildmanager")

 	}

@@ -3,11 +3,13 @@ package images // import "github.com/docker/docker/daemon/images"

 import (

 	"context"

 	"fmt"

+	"strconv"

 	"sync/atomic"

 	"time"

 	"github.com/docker/distribution/reference"

 	"github.com/docker/docker/api/types"

+	"github.com/docker/docker/api/types/events"

 	"github.com/docker/docker/api/types/filters"

 	timetypes "github.com/docker/docker/api/types/time"

 	"github.com/docker/docker/errdefs"

@@ -159,7 +161,11 @@ deleteImagesLoop:

 	if canceled {

 		logrus.Debugf("ImagesPrune operation cancelled: %#v", *rep)

 	}

-

+	i.eventsService.Log("prune", events.ImageEventType, events.Actor{

+		Attributes: map[string]string{

+			"reclaimed": strconv.FormatUint(rep.SpaceReclaimed, 10),

+		},

+	})

 	return rep, nil

 }

@@ -4,10 +4,12 @@ import (

 	"context"

 	"fmt"

 	"regexp"

+	"strconv"

 	"sync/atomic"

 	"time"

 	"github.com/docker/docker/api/types"

+	"github.com/docker/docker/api/types/events"

 	"github.com/docker/docker/api/types/filters"

 	timetypes "github.com/docker/docker/api/types/time"

 	"github.com/docker/docker/errdefs"

@@ -84,7 +86,9 @@ func (daemon *Daemon) ContainersPrune(ctx context.Context, pruneFilters filters.

 			rep.ContainersDeleted = append(rep.ContainersDeleted, c.ID)

 		}

 	}

-

+	daemon.EventsService.Log("prune", events.ContainerEventType, events.Actor{

+		Attributes: map[string]string{"reclaimed": strconv.FormatUint(rep.SpaceReclaimed, 10)},

+	})

 	return rep, nil

 }

@@ -210,7 +214,9 @@ func (daemon *Daemon) NetworksPrune(ctx context.Context, pruneFilters filters.Ar

 		return rep, nil

 	default:

 	}

-

+	daemon.EventsService.Log("prune", events.NetworkEventType, events.Actor{

+		Attributes: map[string]string{"reclaimed": "0"},

+	})

 	return rep, nil

 }

@@ -17,6 +17,10 @@ keywords: "API, Docker, rcli, REST, documentation"

 [Docker Engine API v1.41](https://docs.docker.com/engine/api/v1.41/) documentation

+* `GET /events` now returns `prune` events after pruning resources have completed.

+  Prune events are returned for `container`, `network`, `volume`, `image`, and

+  `builder`, and have a `reclaimed` attribute, indicating the amount of space

+  reclaimed (in bytes).

 * `GET /info` now returns a `CgroupVersion` field, containing the cgroup version.

 * `GET /info` now returns a `DefaultAddressPools` field, containing a list of

   custom default address pools for local networks, which can be specified in the

@@ -2,6 +2,7 @@ package service // import "github.com/docker/docker/volume/service"

 import (

 	"context"

+	"strconv"

 	"sync/atomic"

 	"github.com/docker/docker/api/types"

@@ -238,6 +239,9 @@ func (s *VolumesService) Prune(ctx context.Context, filter filters.Args) (*types

 		rep.SpaceReclaimed += uint64(vSize)

 		rep.VolumesDeleted = append(rep.VolumesDeleted, v.Name())

 	}

+	s.eventLogger.LogVolumeEvent("", "prune", map[string]string{

+		"reclaimed": strconv.FormatInt(int64(rep.SpaceReclaimed), 10),

+	})

 	return rep, nil

 }