[Question]: Iteration component only processes first element of array from Code node in v0.24.0

[modmodleon]

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Describe your problem

Title: Iteration component only processes first element of array from Code node in v0.24.0

Version: 0.24.0

Description:

I have a Code node that outputs an array: ["a", "b", "c"] (type: Array<String>).

This array is passed to an Iteration node via the query variable. Inside the Iteration, the IterationItem is connected to a Knowledge Retrieval node.

The workflow runs without errors, but only the first element "a" is processed and retrieved. The elements "b" and "c" are ignored.

Steps to Reproduce:

1. Create a Code node with the following:

   • Code: return ["a", "b", "c"]
   • Return value: tempList as Array<String>

2. Create an Iteration node.

   • Query variable: set to {code_node.tempList}

3. Inside the Iteration, connect IterationItem to a Knowledge Retrieval node.

   • Knowledge Retrieval query: set to {item}

4. Run the Agent.

Expected Behavior:

The Iteration should process all three elements: "a", "b", and "c". The Knowledge Retrieval node should execute three times, once for each element.

Actual Behavior:

Only "a" is processed. The Knowledge Retrieval node executes only once, returning results only for "a".

Additional Context:

• The Code node output is confirmed correct (logs show ["a","b","c"])
• The Iteration node can see and select the array variable from the Code node
• No error messages are shown
• The issue occurs in v0.24.0

Question:

Is this a bug in v0.24.0, or is there a different configuration required to make Iteration process all elements of an array from a Code node?

[hyl64]

I dug into the current iteration runtime and found an output-contract inconsistency around IterationItem.

At the moment, existing RAGFlow iteration DSL/examples still reference IterationItem@result, while the runtime implementation only exposed item/index. I'm testing a compatibility fix around that path now, since it can explain why downstream nodes only see a partial / wrong iteration payload depending on how the variable was wired.

I'll follow up with a PR or a more concrete reproduction once I finish validating the full execution path.

[hyl64]

Quick update after validating this on a local runtime harness:

• the Iteration runtime itself does iterate through all array elements correctly
• I verified a minimal Canvas.run() path where the child node receives a / b / c across 3 iterations
• the concrete inconsistency I found is on IterationItem outputs: existing iteration DSL/examples still reference IterationItem@result, but the runtime only exposed item / index before the fix

I patched that compatibility gap locally and added focused unit coverage around it. If I turn this into a PR, the scope will be: make IterationItem@result work again without breaking the current @item path.

[modmodleon]

great , thx