daemon: align build.DiskUsage() with other disk-usages

Move calculation of the data to the builder backend, to align with
the other type of objects. This also allows us to skip the verbose
data if it's not used.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/internal/builder-next/builder.go

@@ -150,15 +150,26 @@ func (b *Builder) Cancel(ctx context.Context, id string) error {
 }
 
 // DiskUsage returns a report about space used by build cache
-func (b *Builder) DiskUsage(ctx context.Context) ([]build.CacheRecord, error) {
+func (b *Builder) DiskUsage(ctx context.Context, options buildbackend.DiskUsageOptions) (*buildbackend.DiskUsage, error) {
 	duResp, err := b.controller.DiskUsage(ctx, &controlapi.DiskUsageRequest{})
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("error getting build cache usage: %w", err)
 	}
 
-	var items []build.CacheRecord
+	var usage buildbackend.DiskUsage
 	for _, r := range duResp.Record {
-		items = append(items, build.CacheRecord{
+		usage.TotalCount++
+		usage.TotalSize += r.Size
+		if r.InUse {
+			usage.ActiveCount++
+		}
+		if !r.InUse && !r.Shared {
+			usage.Reclaimable += r.Size
+		}
+		if !options.Verbose {
+			continue
+		}
+		usage.Items = append(usage.Items, build.CacheRecord{
 			ID:          r.ID,
 			Parents:     r.Parents,
 			Type:        r.RecordType,
@@ -182,7 +193,7 @@ func (b *Builder) DiskUsage(ctx context.Context) ([]build.CacheRecord, error) {
 			UsageCount: int(r.UsageCount),
 		})
 	}
-	return items, nil
+	return &usage, nil
 }
 
 // Prune clears all reclaimable build cache.

daemon/server/buildbackend/build.go

@@ -11,6 +11,13 @@ import (
 	"github.com/moby/moby/v2/daemon/internal/filters"
 )
 
+type DiskUsageOptions struct {
+	Verbose bool
+}
+
+// DiskUsage contains disk usage for the build cache.
+type DiskUsage = build.DiskUsage
+
 type CachePruneOptions struct {
 	All           bool
 	ReservedSpace int64

daemon/server/router/system/backend.go

@@ -4,13 +4,13 @@ import (
 	"context"
 	"time"
 
-	"github.com/moby/moby/api/types/build"
 	"github.com/moby/moby/api/types/events"
 	"github.com/moby/moby/api/types/registry"
 	"github.com/moby/moby/api/types/swarm"
 	"github.com/moby/moby/api/types/system"
 	"github.com/moby/moby/v2/daemon/internal/filters"
 	"github.com/moby/moby/v2/daemon/server/backend"
+	"github.com/moby/moby/v2/daemon/server/buildbackend"
 )
 
 // Backend is the methods that need to be implemented to provide
@@ -32,7 +32,7 @@ type ClusterBackend interface {
 
 // BuildBackend provides build specific system information.
 type BuildBackend interface {
-	DiskUsage(context.Context) ([]build.CacheRecord, error)
+	DiskUsage(context.Context, buildbackend.DiskUsageOptions) (*buildbackend.DiskUsage, error)
 }
 
 // StatusProvider provides methods to get the swarm status of the current node.

daemon/server/router/system/system_routes.go

@@ -24,6 +24,7 @@ import (
 	"github.com/moby/moby/v2/daemon/internal/timestamp"
 	"github.com/moby/moby/v2/daemon/internal/versions"
 	"github.com/moby/moby/v2/daemon/server/backend"
+	"github.com/moby/moby/v2/daemon/server/buildbackend"
 	"github.com/moby/moby/v2/daemon/server/httputils"
 	"github.com/moby/moby/v2/daemon/server/router/build"
 	"github.com/moby/moby/v2/pkg/ioutils"
@@ -197,11 +198,13 @@ func (s *systemRouter) getDiskUsage(ctx context.Context, w http.ResponseWriter,
 		})
 	}
 
-	var buildCache []buildtypes.CacheRecord
+	var buildCacheUsage *buildbackend.DiskUsage
 	if getBuildCache {
 		eg.Go(func() error {
 			var err error
-			buildCache, err = s.builder.DiskUsage(ctx)
+			buildCacheUsage, err = s.builder.DiskUsage(ctx, buildbackend.DiskUsageOptions{
+				Verbose: verbose || legacyFields,
+			})
 			if err != nil {
 				return errors.Wrap(err, "error getting build cache usage")
 			}
@@ -257,35 +260,18 @@ func (s *systemRouter) getDiskUsage(ctx context.Context, w http.ResponseWriter,
 			v.VolumeUsage.Items = diskUsage.Volumes.Items
 		}
 	}
-	if getBuildCache {
+	if buildCacheUsage != nil {
 		v.BuildCacheUsage = &buildtypes.DiskUsage{
-			TotalCount: int64(len(buildCache)),
+			ActiveCount: buildCacheUsage.ActiveCount,
+			Reclaimable: buildCacheUsage.Reclaimable,
+			TotalCount:  buildCacheUsage.TotalCount,
+			TotalSize:   buildCacheUsage.TotalSize,
 		}
 
-		activeCount := v.BuildCacheUsage.TotalCount
-		var totalSize, reclaimable int64
-
-		for _, b := range buildCache {
-			if versions.LessThan(version, "1.42") {
-				totalSize += b.Size
-			}
-
-			if !b.InUse {
-				activeCount--
-			}
-			if !b.InUse && !b.Shared {
-				reclaimable += b.Size
-			}
-		}
-
-		v.BuildCacheUsage.ActiveCount = activeCount
-		v.BuildCacheUsage.TotalSize = totalSize
-		v.BuildCacheUsage.Reclaimable = reclaimable
-
 		if legacyFields {
-			v.BuildCache = nonNilSlice(buildCache) //nolint: staticcheck,SA1019: kept to maintain backwards compatibility with API < v1.52.
+			v.BuildCache = nonNilSlice(buildCacheUsage.Items) //nolint: staticcheck,SA1019: kept to maintain backwards compatibility with API < v1.52.
 		} else if verbose {
-			v.BuildCacheUsage.Items = buildCache
+			v.BuildCacheUsage.Items = buildCacheUsage.Items
 		}
 	}
 	return httputils.WriteJSON(w, http.StatusOK, v)