Enhance LoraStackerMapper and WorkflowParser functionality

- Updated LoraStackerMapper to handle multiple formats for lora_stack input, improving flexibility in processing existing stacks.
- Introduced caching for processed node results in WorkflowParser to optimize performance and prevent redundant processing.
- Added a new method to collect loras from model inputs, enhancing the ability to extract relevant data from the workflow.
- Improved handling of processed nodes to avoid cycles and ensure accurate results during workflow parsing.

py/workflow/parser.py

@@ -18,6 +18,7 @@ class WorkflowParser:
     def __init__(self, load_extensions_on_init: bool = True):
         """Initialize the parser with mappers"""
         self.processed_nodes: Set[str] = set()  # Track processed nodes to avoid cycles
+        self.node_results_cache: Dict[str, Any] = {}  # Cache for processed node results
         
         # Load extensions if requested
         if load_extensions_on_init:
@@ -25,14 +26,19 @@ class WorkflowParser:
     
     def process_node(self, node_id: str, workflow: Dict) -> Any:
         """Process a single node and extract relevant information"""
-        # Check if we've already processed this node to avoid cycles
+        # Return cached result if available
+        if node_id in self.node_results_cache:
+            return self.node_results_cache[node_id]
+            
+        # Check if we're in a cycle
         if node_id in self.processed_nodes:
             return None
         
-        # Mark this node as processed
+        # Mark this node as being processed (to detect cycles)
         self.processed_nodes.add(node_id)
         
         if node_id not in workflow:
+            self.processed_nodes.remove(node_id)
             return None
         
         node_data = workflow[node_id]
@@ -43,6 +49,8 @@ class WorkflowParser:
         if mapper:
             try:
                 result = mapper.process(node_id, node_data, workflow, self)
+                # Cache the result
+                self.node_results_cache[node_id] = result
             except Exception as e:
                 logger.error(f"Error processing node {node_id} of type {node_type}: {e}", exc_info=True)
                 # Return a partial result or None depending on how we want to handle errors
@@ -52,6 +60,33 @@ class WorkflowParser:
         self.processed_nodes.remove(node_id)
         return result
     
+    def collect_loras_from_model(self, model_input: List, workflow: Dict) -> str:
+        """Collect loras information from the model node chain"""
+        if not isinstance(model_input, list) or len(model_input) != 2:
+            return ""
+            
+        model_node_id, _ = model_input
+        # Convert node_id to string if it's an integer
+        if isinstance(model_node_id, int):
+            model_node_id = str(model_node_id)
+            
+        # Process the model node
+        model_result = self.process_node(model_node_id, workflow)
+        
+        # If this is a Lora Loader node, return the loras text
+        if model_result and isinstance(model_result, dict) and "loras" in model_result:
+            return model_result["loras"]
+            
+        # If not a lora loader, check the node's inputs for a model connection
+        node_data = workflow.get(model_node_id, {})
+        inputs = node_data.get("inputs", {})
+        
+        # If this node has a model input, follow that path
+        if "model" in inputs and isinstance(inputs["model"], list):
+            return self.collect_loras_from_model(inputs["model"], workflow)
+            
+        return ""
+    
     def parse_workflow(self, workflow_data: Union[str, Dict], output_path: Optional[str] = None) -> Dict:
         """
         Parse the workflow and extract generation parameters
@@ -69,8 +104,9 @@ class WorkflowParser:
         else:
             workflow = workflow_data
             
-        # Reset the processed nodes tracker
+        # Reset the processed nodes tracker and cache
         self.processed_nodes = set()
+        self.node_results_cache = {}
         
         # Find the KSampler node
         ksampler_node_id = find_node_by_type(workflow, "KSampler")
@@ -117,6 +153,18 @@ class WorkflowParser:
                 if "guidance" in node_inputs:
                     result["gen_params"]["guidance"] = node_inputs["guidance"]
         
+        # Extract loras from the model input of KSampler
+        ksampler_node = workflow.get(ksampler_node_id, {})
+        ksampler_inputs = ksampler_node.get("inputs", {})
+        if "model" in ksampler_inputs and isinstance(ksampler_inputs["model"], list):
+            loras_text = self.collect_loras_from_model(ksampler_inputs["model"], workflow)
+            if loras_text:
+                result["loras"] = loras_text
+        
+        # Handle standard ComfyUI names vs our output format
+        if "cfg" in result["gen_params"]:
+            result["gen_params"]["cfg_scale"] = result["gen_params"].pop("cfg")
+            
         # Add clip_skip = 2 to match reference output if not already present
         if "clip_skip" not in result["gen_params"]:
             result["gen_params"]["clip_skip"] = "2"