refactor: how to add a node type in workflow (#558)

backend/domain/workflow/internal/schema/stream.go

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2025 coze-dev Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package schema
+
+import (
+	"github.com/cloudwego/eino/compose"
+
+	"github.com/coze-dev/coze-studio/backend/domain/workflow/entity/vo"
+)
+
+type FieldStreamType string
+
+const (
+	FieldIsStream    FieldStreamType = "yes"     // absolutely a stream
+	FieldNotStream   FieldStreamType = "no"      // absolutely not a stream
+	FieldMaybeStream FieldStreamType = "maybe"   // maybe a stream, requires request-time resolution
+	FieldSkipped     FieldStreamType = "skipped" // the field source's node is skipped
+)
+
+type FieldSkipStatus string
+
+// SourceInfo contains stream type for a input field source of a node.
+type SourceInfo struct {
+	// IsIntermediate means this field is itself not a field source, but a map containing one or more field sources.
+	IsIntermediate bool
+	// FieldType the stream type of the field. May require request-time resolution in addition to compile-time.
+	FieldType FieldStreamType
+	// FromNodeKey is the node key that produces this field source. empty if the field is a static value or variable.
+	FromNodeKey vo.NodeKey
+	// FromPath is the path of this field source within the source node. empty if the field is a static value or variable.
+	FromPath compose.FieldPath
+	TypeInfo *vo.TypeInfo
+	// SubSources are SourceInfo for keys within this intermediate Map(Object) field.
+	SubSources map[string]*SourceInfo
+}
+
+func (s *SourceInfo) Skipped() bool {
+	if !s.IsIntermediate {
+		return s.FieldType == FieldSkipped
+	}
+
+	for _, sub := range s.SubSources {
+		if !sub.Skipped() {
+			return false
+		}
+	}
+
+	return true
+}
+
+func (s *SourceInfo) FromNode(nodeKey vo.NodeKey) bool {
+	if !s.IsIntermediate {
+		return s.FromNodeKey == nodeKey
+	}
+
+	for _, sub := range s.SubSources {
+		if sub.FromNode(nodeKey) {
+			return true
+		}
+	}
+
+	return false
+}