Add Dumas JSON array iterator node

README.md

@@ -39,6 +39,11 @@
   - Output: `INT`
   - Returns the length of a JSON array.
 
+- `Dumas JSON Array Iterator`
+  - Inputs: `json_input`, `index`, `mode`
+  - Outputs: `item`, `current_index`, `total_items`
+  - Returns the current array item and position, with `mode` set to `fixed`, `incr`, or `decr`.
+
 All nodes live in the `Dumas/JSON` category.
 
 ## Installation
@@ -77,6 +82,14 @@ settings.render.width
 {"enabled": true, "retries": 3}
 ```
 
+`Dumas JSON Array Iterator` clamps to valid bounds:
+
+```text
+fixed -> use index as-is
+incr  -> use index + 1
+decr  -> use index - 1
+```
+
 ## Roadmap
 
 This repo is intended to grow into a broader set of Dumas-branded generic utility nodes, including JSON helpers and adjacent data-manipulation tools.

dumas_json_nodes.py

@@ -86,6 +86,18 @@ def _merge_json_objects(base_object, overlay_object):
     return merged
 
 
+def _resolve_iteration_index(index, mode, total_items):
+    if total_items <= 0:
+        return -1
+
+    if mode == "incr":
+        index += 1
+    elif mode == "decr":
+        index -= 1
+
+    return max(0, min(index, total_items - 1))
+
+
 class DumasJSONStringToObjectNode:
     CATEGORY = "Dumas/JSON"
     RETURN_TYPES = ("JSON",)
@@ -230,6 +242,34 @@ class DumasJSONArrayLengthNode:
         return (len(json_array),)
 
 
+class DumasJSONArrayIteratorNode:
+    CATEGORY = "Dumas/JSON"
+    RETURN_TYPES = ("JSON", "INT", "INT")
+    RETURN_NAMES = ("item", "current_index", "total_items")
+    FUNCTION = "iterate"
+
+    @classmethod
+    def INPUT_TYPES(cls):
+        return {
+            "required": {
+                "json_input": ("JSON",),
+                "index": ("INT", {"default": 0, "min": 0, "step": 1}),
+                "mode": (["fixed", "incr", "decr"], {"default": "fixed"}),
+            }
+        }
+
+    def iterate(self, json_input, index, mode):
+        if not isinstance(json_input, list):
+            return (None, -1, 0)
+
+        total_items = len(json_input)
+        if total_items == 0:
+            return (None, -1, 0)
+
+        current_index = _resolve_iteration_index(index, mode, total_items)
+        return (json_input[current_index], current_index, total_items)
+
+
 NODE_CLASS_MAPPINGS = {
     "DumasJSONStringToObject": DumasJSONStringToObjectNode,
     "DumasJSONObjectToString": DumasJSONObjectToStringNode,
@@ -238,6 +278,7 @@ NODE_CLASS_MAPPINGS = {
     "DumasJSONMergeObjects": DumasJSONMergeObjectsNode,
     "DumasJSONKeys": DumasJSONKeysNode,
     "DumasJSONArrayLength": DumasJSONArrayLengthNode,
+    "DumasJSONArrayIterator": DumasJSONArrayIteratorNode,
 }
 
 NODE_DISPLAY_NAME_MAPPINGS = {
@@ -248,4 +289,5 @@ NODE_DISPLAY_NAME_MAPPINGS = {
     "DumasJSONMergeObjects": "Dumas JSON Merge Objects",
     "DumasJSONKeys": "Dumas JSON Keys",
     "DumasJSONArrayLength": "Dumas JSON Array Length",
+    "DumasJSONArrayIterator": "Dumas JSON Array Iterator",
 }

tests/test_dumas_json_nodes.py

@@ -2,6 +2,7 @@ import unittest
 
 from dumas_json_nodes import (
     DumasJSONArrayLengthNode,
+    DumasJSONArrayIteratorNode,
     DumasJSONGetValueNode,
     DumasJSONKeysNode,
     DumasJSONMergeObjectsNode,
@@ -73,6 +74,41 @@ class DumasJSONNodeTests(unittest.TestCase):
 
         self.assertEqual(result, (4,))
 
+    def test_array_iterator_fixed_mode_uses_given_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "fixed")
+
+        self.assertEqual(result, ("b", 1, 3))
+
+    def test_array_iterator_incr_mode_advances_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "incr")
+
+        self.assertEqual(result, ("c", 2, 3))
+
+    def test_array_iterator_decr_mode_decrements_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "decr")
+
+        self.assertEqual(result, ("a", 0, 3))
+
+    def test_array_iterator_clamps_out_of_range_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 99, "fixed")
+
+        self.assertEqual(result, ("c", 2, 3))
+
+    def test_array_iterator_handles_empty_arrays(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate([], 0, "fixed")
+
+        self.assertEqual(result, (None, -1, 0))
+
 
 if __name__ == "__main__":
     unittest.main()