API: deprecate BuilderSize in API versions >= 1.42

Roman Volosatovs · thaJeztah · Roman Volosatovs · commit 31348afa194e · 2021-07-12T10:03:49.000+02:00
Co-authored-by: Sebastiaan van Stijn &lt;github@gone.nl&gt;
Signed-off-by: Roman Volosatovs &lt;roman.volosatovs@docker.com&gt;
diff --git a/api/server/router/system/system_routes.go b/api/server/router/system/system_routes.go
@@ -113,12 +113,14 @@ func (s *systemRouter) getDiskUsage(ctx context.Context, w http.ResponseWriter,
 		return err
 	}
 
-	var builderSize int64
-	for _, b := range buildCache {
-		builderSize += b.Size
+	if versions.LessThan(httputils.VersionFromContext(ctx), "1.42") {
+		var builderSize int64
+		for _, b := range buildCache {
+			builderSize += b.Size
+		}
+		du.BuilderSize = builderSize
 	}
 
-	du.BuilderSize = builderSize
 	du.BuildCache = buildCache
 	if buildCache == nil {
 		// Ensure empty `BuildCache` field is represented as empty JSON array(`[]`)
diff --git a/api/types/types.go b/api/types/types.go
@@ -538,7 +538,7 @@ type DiskUsage struct {
 	Containers  []*Container
 	Volumes     []*Volume
 	BuildCache  []*BuildCache
-	BuilderSize int64 // deprecated
+	BuilderSize int64 `json:",omitempty"` // Deprecated: deprecated in API 1.38, and no longer used since API 1.40.
 }
 
 // ContainersPruneReport contains the response for Engine API:
diff --git a/docs/api/version-history.md b/docs/api/version-history.md
@@ -17,6 +17,11 @@ keywords: "API, Docker, rcli, REST, documentation"
 
 [Docker Engine API v1.42](https://docs.docker.com/engine/api/v1.42/) documentation
 
+* Removed the `BuilderSize` field on the `GET /system/df` endpoint. This field
+  was introduced in API 1.31 as part of an experimental feature, and no longer
+  used since API 1.40.
+  Use field `BuildCache` instead to track storage used by the builder component.
+
 ## v1.41 API changes
 
 [Docker Engine API v1.41](https://docs.docker.com/engine/api/v1.41/) documentation

Original file line number	Diff line number	Diff line change
`@@ -538,7 +538,7 @@ type DiskUsage struct {`
`538`	`538`	`Containers []*Container`
`539`	`539`	`Volumes []*Volume`
`540`	`540`	`BuildCache []*BuildCache`
`541`		`- BuilderSize int64 // deprecated`
	`541`	+ BuilderSize int64 `json:",omitempty"` // Deprecated: deprecated in API 1.38, and no longer used since API 1.40.
`542`	`542`	`}`
`543`	`543`
`544`	`544`	`// ContainersPruneReport contains the response for Engine API:`