build: move solveOpt to local struct type

*client.SolveOpt in driver code is only used by build code.
For a clear separation of concerns, move it to an internal
struct type only accessible by BuildWithResultHandler func.

Signed-off-by: CrazyMax <[email protected]>

build/build.go

@@ -519,6 +519,12 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 		}
 	}()
 
+	type reqForNode struct {
+		*resolvedNode
+		so *client.SolveOpt
+	}
+
+	reqForNodes := make(map[string][]*reqForNode)
 	eg, ctx := errgroup.WithContext(ctx)
 
 	for k, opt := range opt {
@@ -528,6 +534,7 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 		if err != nil {
 			logrus.WithError(err).Warn("current commit information was not captured by the build")
 		}
+		var reqn []*reqForNode
 		for _, np := range drivers[k] {
 			if np.Node().Driver.IsMobyDriver() {
 				hasMobyDriver = true
@@ -548,8 +555,12 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 				so.FrontendAttrs[k] = v
 			}
 			defers = append(defers, release)
-			np.SolveOpt = so
+			reqn = append(reqn, &reqForNode{
+				resolvedNode: np,
+				so:           so,
+			})
 		}
+		reqForNodes[k] = reqn
 		for _, at := range opt.Session {
 			if s, ok := at.(interface {
 				SetLogger(progresswriter.Logger)
@@ -562,8 +573,8 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 
 		// validate for multi-node push
 		if hasMobyDriver && multiDriver {
-			for _, np := range drivers[k] {
-				for _, e := range np.SolveOpt.Exports {
+			for _, np := range reqForNodes[k] {
+				for _, e := range np.so.Exports {
 					if e.Type == "moby" {
 						if ok, _ := strconv.ParseBool(e.Attrs["push"]); ok {
 							return nil, errors.Errorf("multi-node push can't currently be performed with the docker driver, please switch to a different driver")
@@ -576,9 +587,9 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 
 	// validate that all links between targets use same drivers
 	for name := range opt {
-		dps := drivers[name]
+		dps := reqForNodes[name]
 		for i, dp := range dps {
-			so := drivers[name][i].SolveOpt
+			so := reqForNodes[name][i].so
 			for k, v := range so.FrontendAttrs {
 				if strings.HasPrefix(k, "context:") && strings.HasPrefix(v, "target:") {
 					k2 := strings.TrimPrefix(v, "target:")
@@ -606,7 +617,24 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 	results := waitmap.New()
 
 	multiTarget := len(opt) > 1
-	childTargets := calculateChildTargets(drivers, opt)
+
+	// returns all the targets that depend on current target for reverse index
+	childTargets := func(reqForNodes map[string][]*reqForNode, opt map[string]Options) map[string][]string {
+		out := make(map[string][]string)
+		for name := range opt {
+			dps := reqForNodes[name]
+			for i, dp := range dps {
+				so := reqForNodes[name][i].so
+				for k, v := range so.FrontendAttrs {
+					if strings.HasPrefix(k, "context:") && strings.HasPrefix(v, "target:") {
+						target := resultKey(dp.driverIndex, strings.TrimPrefix(v, "target:"))
+						out[target] = append(out[target], resultKey(dp.driverIndex, name))
+					}
+				}
+			}
+		}
+		return out
+	}(reqForNodes, opt)
 
 	for k, opt := range opt {
 		err := func(k string) error {
@@ -630,7 +658,7 @@ func BuildWithResultHandler(ctx context.Context, nodes []builder.Node, opt map[s
 			for i, dp := range dps {
 				i, dp := i, dp
 				node := dp.Node()
-				so := drivers[k][i].SolveOpt
+				so := reqForNodes[k][i].so
 				if multiDriver {
 					for i, e := range so.Exports {
 						switch e.Type {
@@ -1298,24 +1326,6 @@ func resultKey(index int, name string) string {
 	return fmt.Sprintf("%d-%s", index, name)
 }
 
-// calculateChildTargets returns all the targets that depend on current target for reverse index
-func calculateChildTargets(drivers map[string][]*resolvedNode, opt map[string]Options) map[string][]string {
-	out := make(map[string][]string)
-	for name := range opt {
-		dps := drivers[name]
-		for i, dp := range dps {
-			so := drivers[name][i].SolveOpt
-			for k, v := range so.FrontendAttrs {
-				if strings.HasPrefix(k, "context:") && strings.HasPrefix(v, "target:") {
-					target := resultKey(dp.driverIndex, strings.TrimPrefix(v, "target:"))
-					out[target] = append(out[target], resultKey(dp.driverIndex, name))
-				}
-			}
-		}
-	}
-	return out
-}
-
 func waitContextDeps(ctx context.Context, index int, results *waitmap.Map, so *client.SolveOpt) error {
 	m := map[string]string{}
 	for k, v := range so.FrontendAttrs {

build/driver.go

@@ -19,8 +19,6 @@ import (
 )
 
 type resolvedNode struct {
-	SolveOpt *client.SolveOpt
-
 	resolver    *nodeResolver
 	driverIndex int
 	platforms   []specs.Platform