[BUG] Script Node in Custom Workflow Cannot Access Properties of Custom File Uploaded URL—Input Argument Returns NULL

[nne998]

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Dify version

0.10

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. Create a custom workflow.
2. Add a custom file (image) input variable in the "start" node.
3. Add a script node and set the image's URL property as an input argument. Print the input argument for debugging.

✔️ Expected Behavior

Got the url

❌ Actual Behavior

Got null

[nne998]

example.zip

[dosubot]

The issue you're experiencing, where a script node in a custom workflow returns null for a custom file uploaded URL, might be due to the variable not being correctly retrieved from the variable_pool. This can happen if the variable selector used in the script node does not match any existing variable in the variable_pool.

To troubleshoot this, ensure that the variable selector in your script node is correctly configured to match the variable name used in the "start" node. If the variable is not found, the script node will return null, as indicated by the following code snippet:

variable = self.graph_runtime_state.variable_pool.get(variable_selector.value_selector)
if variable is None:
    return NodeRunResult(
        status=WorkflowNodeExecutionStatus.FAILED,
        inputs=variables,
        error=f"Variable `{variable_selector.value_selector}` not found",
    )

This snippet shows that if the variable is not found, the node execution will fail, and the input argument will be null ^[1]. Double-check the variable names and ensure they are consistent across your workflow nodes.

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[crazywoola]

See #9567 for details, this is not a bug, this is still under our UI/UX review.