Merge pull request #1269 from hinshun/ref-array

Change result type to array of refs

frontend/gateway/gateway.go

@@ -475,7 +475,16 @@ func (lbf *llbBridgeForwarder) Solve(ctx context.Context, req *pb.SolveRequest)
 			}
 			ids[k] = id
 		}
-		pbRes.Result = &pb.Result_Refs{Refs: &pb.RefMap{Refs: ids}}
+
+		if req.AllowResultArrayRef {
+			refMap := make(map[string]*pb.Ref, len(res.Refs))
+			for k, id := range ids {
+				refMap[k] = pb.NewRef(id)
+			}
+			pbRes.Result = &pb.Result_Refs{Refs: &pb.RefMap{Refs: refMap}}
+		} else {
+			pbRes.Result = &pb.Result_RefsDeprecated{RefsDeprecated: &pb.RefMapDeprecated{Refs: ids}}
+		}
 	} else {
 		id := identity.NewID()
 		if res.Ref == nil {
@@ -484,7 +493,12 @@ func (lbf *llbBridgeForwarder) Solve(ctx context.Context, req *pb.SolveRequest)
 			lbf.refs[id] = res.Ref
 		}
 		defaultID = id
-		pbRes.Result = &pb.Result_Ref{Ref: id}
+
+		if req.AllowResultArrayRef {
+			pbRes.Result = &pb.Result_Ref{Ref: pb.NewRef(id)}
+		} else {
+			pbRes.Result = &pb.Result_RefDeprecated{RefDeprecated: id}
+		}
 	}
 	lbf.mu.Unlock()
 
@@ -635,16 +649,42 @@ func (lbf *llbBridgeForwarder) Return(ctx context.Context, in *pb.ReturnRequest)
 		}
 
 		switch res := in.Result.Result.(type) {
+		case *pb.Result_RefDeprecated:
+			var ids []string
+			if res.RefDeprecated != "" {
+				ids = append(ids, res.RefDeprecated)
+			}
+
+			ref, err := lbf.convertRef(ids)
+			if err != nil {
+				return nil, err
+			}
+			r.Ref = ref
+		case *pb.Result_RefsDeprecated:
+			m := map[string]solver.CachedResult{}
+			for k, v := range res.RefsDeprecated.Refs {
+				var ids []string
+				if v != "" {
+					ids = append(ids, v)
+				}
+
+				ref, err := lbf.convertRef(ids)
+				if err != nil {
+					return nil, err
+				}
+				m[k] = ref
+			}
+			r.Refs = m
 		case *pb.Result_Ref:
-			ref, err := lbf.convertRef(res.Ref)
+			ref, err := lbf.convertRef(res.Ref.Ids)
 			if err != nil {
 				return nil, err
 			}
 			r.Ref = ref
 		case *pb.Result_Refs:
 			m := map[string]solver.CachedResult{}
-			for k, v := range res.Refs.Refs {
-				ref, err := lbf.convertRef(v)
+			for k, ref := range res.Refs.Refs {
+				ref, err := lbf.convertRef(ref.Ids)
 				if err != nil {
 					return nil, err
 				}
@@ -656,16 +696,24 @@ func (lbf *llbBridgeForwarder) Return(ctx context.Context, in *pb.ReturnRequest)
 	}
 }
 
-func (lbf *llbBridgeForwarder) convertRef(id string) (solver.CachedResult, error) {
-	if id == "" {
+func (lbf *llbBridgeForwarder) convertRef(ids []string) (solver.CachedResult, error) {
+	if len(ids) == 0 {
 		return nil, nil
 	}
+
+	if len(ids) > 1 {
+		return nil, errors.Errorf("return reference has multi-result array")
+	}
+
 	lbf.mu.Lock()
 	defer lbf.mu.Unlock()
+
+	id := ids[0]
 	r, ok := lbf.refs[id]
 	if !ok {
 		return nil, errors.Errorf("return reference %s not found", id)
 	}
+
 	return r, nil
 }
 

frontend/gateway/grpcclient/client.go

@@ -105,14 +105,14 @@ func (c *grpcClient) Run(ctx context.Context, f client.BuildFunc) (retError erro
 					Metadata: res.Metadata,
 				}
 				if res.Refs != nil {
-					m := map[string]string{}
+					m := map[string]*pb.Ref{}
 					for k, r := range res.Refs {
 						id, err := convertRef(r)
 						if err != nil {
 							retError = err
 							continue
 						}
-						m[k] = id
+						m[k] = pb.NewRef(id)
 					}
 					pbRes.Result = &pb.Result_Refs{Refs: &pb.RefMap{Refs: m}}
 				} else {
@@ -120,7 +120,7 @@ func (c *grpcClient) Run(ctx context.Context, f client.BuildFunc) (retError erro
 					if err != nil {
 						retError = err
 					} else {
-						pbRes.Result = &pb.Result_Ref{Ref: id}
+						pbRes.Result = &pb.Result_Ref{Ref: pb.NewRef(id)}
 					}
 				}
 				if retError == nil {
@@ -280,10 +280,11 @@ func (c *grpcClient) Solve(ctx context.Context, creq client.SolveRequest) (*clie
 	}
 
 	req := &pb.SolveRequest{
-		Definition:        creq.Definition,
-		Frontend:          creq.Frontend,
-		FrontendOpt:       creq.FrontendOpt,
-		AllowResultReturn: true,
+		Definition:          creq.Definition,
+		Frontend:            creq.Frontend,
+		FrontendOpt:         creq.FrontendOpt,
+		AllowResultReturn:   true,
+		AllowResultArrayRef: true,
 		// old API
 		ImportCacheRefsDeprecated: legacyRegistryCacheImports,
 		// new API
@@ -310,18 +311,37 @@ func (c *grpcClient) Solve(ctx context.Context, creq client.SolveRequest) (*clie
 	} else {
 		res.Metadata = resp.Result.Metadata
 		switch pbRes := resp.Result.Result.(type) {
-		case *pb.Result_Ref:
-			if id := pbRes.Ref; id != "" {
+		case *pb.Result_RefDeprecated:
+			if id := pbRes.RefDeprecated; id != "" {
 				res.SetRef(&reference{id: id, c: c})
 			}
-		case *pb.Result_Refs:
-			for k, v := range pbRes.Refs.Refs {
+		case *pb.Result_RefsDeprecated:
+			for k, v := range pbRes.RefsDeprecated.Refs {
 				ref := &reference{id: v, c: c}
 				if v == "" {
 					ref = nil
 				}
 				res.AddRef(k, ref)
 			}
+		case *pb.Result_Ref:
+			ids := pbRes.Ref.Ids
+			if len(ids) > 0 {
+				if len(ids) > 1 {
+					return nil, errors.Errorf("solve returned multi-result array")
+				}
+				res.SetRef(&reference{id: ids[0], c: c})
+			}
+		case *pb.Result_Refs:
+			for k, v := range pbRes.Refs.Refs {
+				var ref *reference
+				if len(v.Ids) > 0 {
+					if len(v.Ids) > 1 {
+						return nil, errors.Errorf("solve returned multi-result array")
+					}
+					ref = &reference{id: v.Ids[0], c: c}
+				}
+				res.AddRef(k, ref)
+			}
 		}
 	}
 

frontend/gateway/pb/gateway.proto

@@ -30,16 +30,28 @@ service LLBBridge {
 
 message Result {
 	oneof result {
-		string ref = 1;
-		RefMap refs = 2;
+    		// Deprecated non-array refs.
+		string refDeprecated = 1;
+		RefMapDeprecated refsDeprecated = 2;
+
+		Ref ref = 3;
+		RefMap refs = 4;
 	}
 	map<string, bytes> metadata = 10;
 }
 
-message RefMap {
+message RefMapDeprecated {
 	map<string, string> refs = 1;
 }
 
+message Ref {
+	repeated string ids = 1;
+}
+
+message RefMap {
+	map<string, Ref> refs = 1;
+}
+
 message ReturnRequest {
 	Result result = 1;
 	google.rpc.Status error = 2;
@@ -70,6 +82,7 @@ message SolveRequest {
         // for each of the ImportCacheRefs entry to CacheImports for compatibility. (planned to be removed)
 	repeated string ImportCacheRefsDeprecated = 4;
 	bool allowResultReturn = 5;
+	bool allowResultArrayRef = 6;
 	
 	// apicaps.CapSolveInlineReturn deprecated
 	bool Final = 10;

frontend/gateway/pb/ref.go

@@ -0,0 +1,9 @@
+package moby_buildkit_v1_frontend
+
+func NewRef(id string) *Ref {
+	var ref Ref
+	if id != "" {
+		ref.Ids = append(ref.Ids, id)
+	}
+	return &ref
+}