feat: add JSON Iterator node for array and directory iteration

nodes/json_iterator.py

@@ -0,0 +1,136 @@
+import json
+import os
+import signal
+import sys
+
+# Global counter: key=file_path, value=current_index
+_JSON_ITER_COUNTERS = {}
+
+
+def _interrupt_handler(signum, frame):
+    """Called when the iterator is exhausted, terminating the workflow queue."""
+    print("[JSONIterator] All items iterated. Stopping workflow.")
+    sys.exit(0)
+
+
+class JSONIterator:
+    """
+    Load a local JSON file or a directory containing JSON files and iterate through them.
+    - If a directory is provided: Iterates through all .json files in it.
+    - If a JSON file containing an array is provided: Iterates through its items.
+    - If a regular JSON file is provided: Returns its content (1 iteration).
+    """
+
+    @classmethod
+    def INPUT_TYPES(cls):
+        return {
+            "required": {
+                "file_path": ("STRING", {"default": "", "multiline": False, "placeholder": "/path/to/folder_or_file.json"}),
+                "start_index": ("INT", {"default": 0, "min": 0, "max": 0xffffffffffffffff, "step": 1}),
+                "auto_next": ("BOOLEAN", {"default": True, "label_on": "Auto (iterates each run)", "label_off": "Manual (use start_index)"}),
+                "reset_iterator": ("BOOLEAN", {"default": False, "label_on": "Reset NOW", "label_off": "Continue"}),
+            },
+        }
+
+    RETURN_TYPES = ("STRING", "INT", "INT")
+    RETURN_NAMES = ("json_string", "current_index", "total_items")
+    FUNCTION = "iterate"
+    CATEGORY = "🚦ComfyUI_LLMs_Toolkit/JSON"
+
+    @classmethod
+    def IS_CHANGED(cls, file_path, start_index, auto_next, reset_iterator):
+        # Always re-run so the counter can advance each execution
+        return float("NaN")
+
+    def iterate(self, file_path, start_index, auto_next, reset_iterator):
+        global _JSON_ITER_COUNTERS
+
+        # --- Validate path ---
+        if not file_path or not os.path.exists(file_path):
+            print(f"[JSONIterator] Path not found: {file_path}")
+            return (f'{{"error": "Path not found: {file_path}"}}', -1, 0)
+
+        data_items = []
+        is_directory = os.path.isdir(file_path)
+
+        # --- Gather items to iterate ---
+        if is_directory:
+            # Case 1: Directory - find all .json files
+            files = [f for f in os.listdir(file_path) if f.lower().endswith('.json')]
+            files.sort()
+            if not files:
+                return (f'{{"error": "No .json files found in directory: {file_path}"}}', -1, 0)
+            data_items = [os.path.join(file_path, f) for f in files]
+        else:
+            # Case 2: Single File
+            try:
+                with open(file_path, 'r', encoding='utf-8') as f:
+                    content = json.load(f)
+                if isinstance(content, list):
+                    # It's an array - iterate its items
+                    data_items = content
+                else:
+                    # It's a single object - wrap it
+                    data_items = [content]
+            except Exception as e:
+                return (f'{{"error": "Failed to load JSON file: {str(e)}"}}', -1, 0)
+
+        total_items = len(data_items)
+        if total_items == 0:
+            return (f'{{"error": "No items to iterate."}}', -1, 0)
+
+        # --- Counter management ---
+        key = file_path
+
+        if reset_iterator or key not in _JSON_ITER_COUNTERS:
+            _JSON_ITER_COUNTERS[key] = start_index
+            if reset_iterator:
+                print(f"[JSONIterator] Iterator reset to index {start_index} for: {file_path}")
+
+        # --- Determine index to use ---
+        if auto_next:
+            current_idx = _JSON_ITER_COUNTERS[key]
+        else:
+            current_idx = start_index
+
+        # --- Check bounds: stop the workflow if exhausted ---
+        if current_idx >= total_items:
+            print(f"[JSONIterator] All {total_items} items iterated. Stopping workflow.")
+            signal.signal(signal.SIGINT, _interrupt_handler)
+            signal.raise_signal(signal.SIGINT)
+            return (f'{{"error": "Iterator exhausted (index {current_idx} >= {total_items})"}}', current_idx, total_items)
+
+        # --- Get current item ---
+        item = data_items[current_idx]
+        
+        # If it's a file path string (from directory iteration), load it
+        if is_directory:
+            try:
+                with open(item, 'r', encoding='utf-8') as f:
+                    final_data = json.load(f)
+                result_str = json.dumps(final_data, ensure_ascii=False)
+            except Exception as e:
+                result_str = f'{{"error": "Failed to load file {item}: {str(e)}"}}'
+        else:
+            # If it's already a loaded item (from array or single object)
+            if isinstance(item, str):
+                result_str = item
+            else:
+                result_str = json.dumps(item, ensure_ascii=False)
+
+        # --- Advance counter ---
+        if auto_next:
+            _JSON_ITER_COUNTERS[key] += 1
+            remaining = total_items - (_JSON_ITER_COUNTERS[key])
+            print(f"[JSONIterator] Output index {current_idx}. Remaining: {remaining}")
+
+        return (result_str, current_idx, total_items)
+
+
+NODE_CLASS_MAPPINGS = {
+    "JSONIterator": JSONIterator
+}
+
+NODE_DISPLAY_NAME_MAPPINGS = {
+    "JSONIterator": "JSON Iterator"
+}