This node allows you to manually start the workflow by clicking on the ‘Test workflow’ in the n8n interface. This node can be replaced either by a webhook call or included in another workflow of yours.

Node Type: Manual Trigger

A custom JavaScript code node is used to set up the parameters and configuration for the image generation process. This includes defining the prompts and settings for the AI model. The code generates a prompt structure necessary for the ComfyUI API to initiate image generation. AS mentioned in the Pre-requisites, you can extract this ComfyUI JSON workflow from the ComfyUI interface, by clicking on the “Save (API Format)” button on the application menu and opening the downloaded file content with a text editor.

We will slightly modified this JSON and define two variables at the top of the JS Script that will need to be recalled inside of the ComfyUI JSON

1. 1. positiveprompt: This define the prompt to be passed to the AI image generation process. We will use this variable inside of the ComfyUI JSON
   2. seednumber: We will generate a random seed number in order to randomize the AI image generation. If you use always use the same seed number and repeat the workflow you will always get the same image generated

Node Type: Code
Language: JavaScript
JavaScript code:

This node evaluates the status of the image generation process status.status_str coming from the response of the previous node If the status is ‘success’, it proceeds to the next step; otherwise, it waits and rechecks the status later awaiting for the ComfyUI image generation process to be finished..

Node Type: If
Condition:

• Left Value: Expression{{ $('ComfyUI - Check Image generation status').item.json[$('3. ComfyUI HTTP Request').item.json.prompt_id].status.status_str }}
• Operator: is equal to
• Right Value: success

This node pauses the workflow for a few seconds if the results of the previous status check is not yet completed before rechecking the status of the image generation process. I have set-up this temporization to 10 seconds, by experience as on my system an image generation in ComfyUI takes between 30sec to 50sec depending on the workflow.

Node Type: Wait
Parameters:

• Resume: After time interval
• Wait amount: 10
• Wait unit: Seconds

Once the image generation is successful, this node retrieves the generated image from the API for viewing or further processing.

Node Type: HTTP Request
Parameters:

• Method: GET
• URL: http://COMFYUI_IP_ADDRESS:COMFYUI_PORT/view
• Query Parameters: Using fields Below, parsed from the response of the previous step
  • filename: The filename of the generated image: {{$json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs[Object.keys($json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs)[0]].images[0].filename}}
  • subfolder: The subfolder where the image is stored. {{$json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs[Object.keys($json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs)[0]].images[0].subfolder}}
  • type: The type of the image: {{$json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs[Object.keys($json[$node["3. ComfyUI HTTP Request"].json.prompt_id].outputs)[0]].images[0].type}}

The recovery of the filename, subfolder,type parameters from the previous node is a bit tricky as the structure of the returned JSON is dynamic depending on the prompt_id

Parameters

Response

  {
    "91fae807-ff1a-4bf0-a493-0c56b0f8fba2": {
      "prompt": [WORKFLOW STEP DESCRIPTION - DELETED FOR MORE CLARITY ] ,
      "outputs": {
        "9": {
          "images": [
            {
              "filename": "ComfyUI_00492_.png",
              "subfolder": "",
              "type": "output"
            }
          ]
        }
      },
      "status": {
        "status_str": "success",
        "completed": true,
        "messages": [
          [
            "execution_start",
            {
              "prompt_id": "91fae807-ff1a-4bf0-a493-0c56b0f8fba2"
            }
          ],
          [
            "execution_cached",
            {
              "nodes": [
                "7",
                "5",
                "4",
                "6"
              ],
              "prompt_id": "91fae807-ff1a-4bf0-a493-0c56b0f8fba2"
            }
          ]
        ]
      }
    }
  }

Parameters

Response