Payment Flow + Access Flow Change

models/workflow/graph/graph.go

@@ -145,6 +145,50 @@ func (g *Graph) GetAverageTimeProcessingBeforeStart(average float64, processingI
 	return max, nil
 }
 
+// DataStorageLink represents a resolved Data→Storage pair found in the graph.
+type DataStorageLink struct {
+	DataItemID    string
+	StorageItemID string
+}
+
+// GetDataStorageLinks returns all links that connect a Data item to a Storage item.
+// These links are mandatory when the Data instance has a Source configured:
+// the workflow builder uses them to know where to download the data before
+// any processing step that consumes that storage.
+func (g *Graph) GetDataStorageLinks() []DataStorageLink {
+	var result []DataStorageLink
+	for _, link := range g.Links {
+		srcItem, srcOk := g.Items[link.Source.ID]
+		dstItem, dstOk := g.Items[link.Destination.ID]
+		if !srcOk || !dstOk {
+			continue
+		}
+		if g.IsData(srcItem) && g.IsStorage(dstItem) {
+			result = append(result, DataStorageLink{
+				DataItemID:    link.Source.ID,
+				StorageItemID: link.Destination.ID,
+			})
+		} else if g.IsStorage(srcItem) && g.IsData(dstItem) {
+			result = append(result, DataStorageLink{
+				DataItemID:    link.Destination.ID,
+				StorageItemID: link.Source.ID,
+			})
+		}
+	}
+	return result
+}
+
+// GetLinkedStorageForData returns the storage item IDs linked to a given Data item.
+func (g *Graph) GetLinkedStorageForData(dataItemID string) []string {
+	var storageIDs []string
+	for _, dsl := range g.GetDataStorageLinks() {
+		if dsl.DataItemID == dataItemID {
+			storageIDs = append(storageIDs, dsl.StorageItemID)
+		}
+	}
+	return storageIDs
+}
+
 func (g *Graph) GetResource(id string) (tools.DataType, resources.ResourceInterface) {
 	if item, ok := g.Items[id]; ok {
 		if item.NativeTool != nil {