ComfyUI Backend API (works with RunComfy Server API)

RunComfy offers two API approaches to suit various integration needs: RunComfy Server API and ComfyUI Backend API These APIs lets you spin up and fully control a dedicated ComfyUI backend. Start by using the Server API to manage machines through simple calls: POST to generate a server_id, poll the status endpoint until it reaches "Ready", and then access the ComfyUI Backend API directly for tasks like executing workflows, managing nodes, and retrieving outputs. This approach is perfect when you need complete oversight of the ComfyUI backend, such as for in-depth integrations with creative software like Krita, Photoshop, Blender, iClone, or other tools. RunComfy Serverless API This API turns any ComfyUI workflow into an on-demand, autoscaling endpoint, enabling simple API calls without any server setup or maintenance. It includes asynchronous job monitoring and versioning for rapid updates, making it ideal for efficient, scalable production setups that can be easily integrated into your apps. For more details, check our Serverless API documentation.

Get ComfyUI Backend URL

1. From RunComfy website in the browser
1. The url appears as https://www.runcomfy.com/comfyui/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/servers/yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy.
2. The actual ComfyUI URL can be found in here, in a format of https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com.
2. From RunComfy API
1. It is the main_service_url in this response.

Note: Please use this ComfyUI URL in a trusted environment, DO NOT SHARE IT publicly.

Activate Development Mode

Ensure that "Enable Development Mode Options" is activated in the Settings menu.

Download the workflow_api.json file by clicking on the Save (API Format) button.

The following file is AnimateDiff + ControlNet + Auto Mask | Restyle Video, which will be used as an example.

Upload Image as Input

import requests

url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/upload/image"

payload = {'overwrite':'true', 'type':'input', 'subfolder':''} # you can safely remove the subfolder field here if you don't need it
files=[
  ('image',('zzzz.png',open('/folder_path/zzzz.png','rb'),'application/octet-stream'))
]
headers = {}

response = requests.post(url, headers=headers, data=payload, files=files)

print(response.json())

Upload Video as Input

import requests

url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/upload/image"

payload = {'overwrite':'true', 'type':'input', 'subfolder':''} # you can safely remove the subfolder field here if you don't need it
files=[
  ('image',('zzzz.mp4',open('/folder_path/zzzz.mp4','rb'),'application/octet-stream'))
]
headers = {}

response = requests.post(url, headers=headers, data=payload, files=files)

print(response.json())

The response will be something like:

{
    "name": "zzzz.mp4",
    "subfolder": "",
    "type": "input"
}

The zzzz.mp4 is the file you uploaded via the API in the input folder. Sometimes it may contain suffixes like '(1)' or '(1)(1)' if a file with the same name already exists.

Queue prompt

Basic HTTP API:

• Generate client_id

import uuid
client_id = str(uuid.uuid4())

• Load workflow_api.json from your local disk and change the input to the file name which you just uploaded in input folder, and also modify the prompt text in the json if you need to.

import json

prompt_data = json.load(open("workflow_api.json"))

prompt_data['89']['inputs']['video'] = 'zzzz.mp4'

• Call the queue prompt api

import requests

url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/prompt"

prompt = {
    "prompt": prompt_data,
    "client_id": client_id
}

headers = {}

response = requests.post(url, headers=headers, json=prompt)

print(response.json())

### response:
{'prompt_id': '10b3da78-cf5f-4ed7-885d-dccf5f3f3c69', 'number': 0, 'node_errors': {}}

• check status
• Reference to https://github.com/comfyanonymous/ComfyUI/blob/master/script_examples/websockets_api_example.py for more details

import websocket
import uuid

ws = websocket.WebSocket()
ws.connect("ws://{}/ws?clientId={}".format('yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com', client_id))
while True:
    out = ws.recv()
    print(out)

• Get Result

import requests
import urllib.parse 

# see the explanation in the next section for the path
def get_image(filename, subfolder, folder_type):
    data = {"filename": filename, "subfolder": subfolder, "type": folder_type}
    url_value = urllib.parse.urlencode(data)
    url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/view?{}".format(url_value)
    response = requests.get(url)
    return response.content

# see the explanation in the next section for the path
def get_video(filename, subfolder, _format):
    data = {"filename": filename, "subfolder": subfolder, "format": _format}
    url_value = urllib.parse.urlencode(data)
    url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/view?{}".format(url_value)
    response = requests.get(url)
    return response.content

prompt_id = '10b3da78-cf5f-4ed7-885d-dccf5f3f3c69' # the response from POST https://comfyui_url/prompt

url = "https://yyyyyyy-yyyy-yyyy-yyyyyyyyyyyy-comfyui.runcomfy.com/history/{}".format(prompt_id)

headers = {}

response = requests.get(url, headers=headers)

data = response.json().get(prompt_id)

video_result = data.get('outputs').get('90').get('gifs')[0]
raw_video = get_video(video_result.get('filename'), video_result.get('subfolder'), video_result.get('format'))

with open(video_result.get('filename'), 'wb') as f:
    f.write(raw_video)

# GET ALL MEDIA OUTPUT FROM WORKFLOW
    
for node_id, node_output in data.get('outputs').items():
    if 'images' in node_output:
        for image in node_output['images']:
            raw_image = get_image(image.get('filename'), image.get('subfolder'), image.get('temp'))
            with open(f"./output/{image.get('filename')}", "wb") as f:
                f.write(raw_image)

    if 'gifs' in node_output:
        for video in node_output['gifs']:            
            raw_video = get_video(video.get('filename'), video.get('subfolder'), video.get('format'))
            with open(f"./output/{video.get('filename')}", "wb") as f:
                f.write(raw_video)
        
    if 'openpose_json' in node_output:
        pass

• Explanation on the url path
• If you want to get the file from the following path, /ComfyUI/output/subfolder1/subfolder2/test_00001_.png, try GET the following url, https://xxx-comfyui.runcomfy.com/api/view?filename=test_00001_.png&subfolder=subfolder1%2Fsubfolder2&type=output