ComfyUI Runner

Runs a ComfyUI workflow via its API

Overview

The ComfyUI Runner node is designed to run a ComfyUI workflow by sending it to a specified ComfyUI instance via its API. It accepts a JSON representation of a ComfyUI workflow and the URL of the running ComfyUI server, then processes this workflow remotely.

This node is useful when you want to automate or integrate ComfyUI workflows within an n8n automation pipeline. For example, you can dynamically generate or modify a ComfyUI workflow in previous nodes and then execute it on a remote ComfyUI server without manual intervention.

Note: The current implementation is a placeholder and does not yet perform the actual API call to ComfyUI. Instead, it returns the input data along with some metadata indicating that the API call is not implemented.

Properties

Name Meaning
ComfyUI URL The base URL of your running ComfyUI instance (e.g., http://localhost:8188). This is where the workflow will be sent for execution.
Workflow JSON The ComfyUI workflow in API JSON format. You can paste the entire workflow here or use expressions to insert dynamic data from previous nodes.

Output

The output contains an array of items corresponding to each input item. Each output item has the following structure:

  • json: Contains the original input JSON merged with additional metadata fields:
    • _comfyRunnerStatus: A placeholder string indicating the API call is not implemented.
    • _receivedUrl: The ComfyUI URL received as input.
    • _receivedWorkflow: The workflow JSON received as input.
  • binary: Empty object (no binary data output).
  • pairedItem: References the index of the input item.

Since the actual API call is not implemented, no real execution results or binary data are returned.

Dependencies

  • Requires a running ComfyUI instance accessible via HTTP at the provided URL.
  • No external API keys or authentication mechanisms are currently handled by the node.
  • No additional environment variables or n8n credentials are required in the current placeholder state.

Troubleshooting

  • Common Issue: Since the API call is not implemented, users expecting actual workflow execution will only see placeholder status messages.
  • Error Handling: If an error occurs during processing, and "Continue On Fail" is enabled, the node outputs an error object containing the error message, stack trace, and the input JSON that caused the failure.
  • Resolution: To fully utilize this node, the API call logic needs to be implemented. Until then, verify that the ComfyUI URL and workflow JSON inputs are correctly formatted to avoid input-related errors.

Links and References

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