Deploy and Run ComfyUI as an API on Inferless

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Introduction

ComfyUI is an open-source graphical user interface for image-generation models, used for generating images from text prompts using node-based approach. It allows users to create complex image generation workflows and offers extensive customization options, making it a powerful tool for AI-driven creativity.

In this tutorial we will show you how you can use your custom workflow with the ComfyUI API on Inferless.

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Overview of the Solution

Our solution revolves around these key files that works together to set up and run ComfyUI on Inferless, alongside an NFS (Network File System) volume for persistent storage.

1. build.sh: This shell script automates the setup of the ComfyUI environment on the NFS volume. It leverages the ComfyUI command-line interface (CLI) to install and configure ComfyUI, ensuring the necessary model weights are downloaded into the specified workspace directory.

   comfy --skip-prompt --workspace=$NFS_VOLUME/ComfyUI install --nvidia
   comfy --skip-prompt model download --url https://huggingface.co/black-forest-labs/FLUX.1-dev/resolve/main/flux1-dev.safetensors --relative-path models/unet --set-civitai-api-token $HF_ACCESS_TOKEN
   comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/t5xxl_fp16.safetensors --relative-path models/clip
   comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/clip_l.safetensors --relative-path models/clip
   comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/t5xxl_fp8_e4m3fn.safetensors --relative-path models/clip
   comfy --skip-prompt model download --url https://huggingface.co/black-forest-labs/FLUX.1-schnell/resolve/main/ae.safetensors --relative-path models/vae
   comfy --skip-prompt model download --url https://huggingface.co/autismanon/modeldump/resolve/main/dreamshaper_8.safetensors --relative-path models/checkpoints
   mkdir -p "$NFS_VOLUME/workflows"
   

2. app.py: This Python script contains the InferlessPythonModel class, which Inferless uses to manage the application lifecycle.

   • The initialize function within this class triggers the build.sh script to set up the environment.
   • The infer function is responsible for processing incoming user requests by interacting with the ComfyUI server to generate images, which it then returns to the user. Additionally, this function handles loading user workflows, updating them with user prompts, and managing the lifecycle of the ComfyUI server.

   import subprocess
   import os
   import uuid
   from comfy_utils import run_comfyui_in_background, check_comfyui, load_workflow, prompt_update_workflow, send_comfyui_request, get_img_file_path, image_to_base64, stop_server_on_port, is_comfyui_running
   import requests
   import json
   
   class InferlessPythonModel:
       def initialize(self):
           self.directory_path = os.getenv('NFS_VOLUME')
           if not os.path.exists(self.directory_path+"/ComfyUI"):
               subprocess.run(["wget", "https://github.com/inferless/ComfyUI-Inferless-template/raw/main/build.sh"])
               subprocess.run(["bash", "build.sh"], check=True)
           
           self._data_dir = self.directory_path+"/workflows"
           self.server_address = "127.0.0.1:8188"
           self.client_id = str(uuid.uuid4())
           
           if is_comfyui_running(self.server_address):
               stop_server_on_port(8188)    
           run_comfyui_in_background(self.directory_path+'/ComfyUI')
           self.ws = check_comfyui(self.server_address,self.client_id)
   
       def infer(self, inputs):
           workflow_input = inputs.get("workflow")
           prompt = inputs.get("prompt")
           negative_prompt = inputs.get("negative_prompt")
           workflow_filename = "workflow_api.json"
           workflow_path = os.path.join(self._data_dir, workflow_filename)
           # Process the workflow input
           if workflow_input.startswith('http://') or workflow_input.startswith('https://'):
               response = requests.get(workflow_input)
               workflow_json = response.json()
           else:
               workflow_json = json.loads(workflow_input)
           
           # Save the workflow JSON to a file
           with open(workflow_path, 'w') as f:
               json.dump(workflow_json, f)
           
           # Load the saved workflow
           workflow = load_workflow(workflow_path)
           prompt = prompt_update_workflow(workflow_filename, workflow, prompt)
           prompt_id = send_comfyui_request(self.ws, prompt, self.server_address, self.client_id)
           file_path = get_img_file_path(self.server_address, prompt_id)
           image_base64 = image_to_base64(self.directory_path+"/ComfyUI"+file_path)
           return {"generated_image_base64": image_base64}
       
       def finalize(self):
           pass
   

3. comfy_utils.py: This utility script have helper functions that streamline our interaction with ComfyUI.

   import json
   import urllib.request
   import time
   import subprocess
   import os
   import websocket
   import threading
   import sys
   import base64
   import requests
   import psutil
   
   def start_comfyui(comfyui_path):
       try:
           
           process = subprocess.Popen(f"comfy --skip-prompt --workspace={comfyui_path} launch -- --listen 127.0.0.1 --port 8188",shell=True)
           # Wait for a short time to see if the process starts successfully
           time.sleep(5)
           
           if process.poll() is None:
               return process
           else:
               stdout, stderr = process.communicate()
               raise Exception("ComfyUI server failed to start")
       except Exception as e:
           raise Exception("Error setting up ComfyUI repo") from e
   
   def run_comfyui_in_background(comfyui_path):
       def run_server():
           process = start_comfyui(comfyui_path)
           if process:
               stdout, stderr = process.communicate()
   
       server_thread = threading.Thread(target=run_server)
       server_thread.start()
   
   def check_comfyui(server_address,client_id):
       socket_connected = False
       while not socket_connected:
           try:
               ws = websocket.WebSocket()
               ws.connect(
                   "ws://{}/ws?clientId={}".format(server_address, client_id)
               )
               socket_connected = True
           except Exception as e:
               time.sleep(5)
       return ws
   
   def load_workflow(workflow_path):
       with open(f"{workflow_path}", 'rb') as file:
           return json.load(file)
   
   def prompt_update_workflow(workflow_name,workflow,prompt,negative_prompt=None):
       workflow["6"]["inputs"]["text"] = prompt
       if negative_prompt:
           workflow["7"]["inputs"]["text"]  = negative_prompt
           
       return workflow
       
   def send_comfyui_request(ws, prompt, server_address,client_id):
       p = {"prompt": prompt,"client_id": client_id}
       data = json.dumps(p).encode("utf-8")
       url = f"http://{server_address}/prompt"
       req = urllib.request.Request(url, data=data, headers={'Content-Type': 'application/json'})
   
       with urllib.request.urlopen(req, timeout=10) as response:
           response = json.loads(response.read())
       
       while True:
           prompt_id = response["prompt_id"]
           out = ws.recv()
           if isinstance(out, str):
               message = json.loads(out)
               if message["type"] == "executing":
                   data = message["data"]
                   if data["node"] is None and data["prompt_id"] == prompt_id:
                       break
           else:
               continue
       return prompt_id
   
   def get_img_file_path(server_address,prompt_id):
       with urllib.request.urlopen(
           "http://{}/history/{}".format(server_address, prompt_id),timeout=10
       ) as response:
           output = json.loads(response.read())
       outputs = output[prompt_id]["outputs"]
       for node_id in outputs:
           node_output = outputs[node_id]
       
       if "images" in node_output:
           image_outputs = []
           for image in node_output["images"]:
                   image_outputs.append({"filename": image.get("filename")})
       
       for node_id in image_outputs:
           file_path = f"/output/{node_id.get('filename')}"
       
       return file_path
   
   def image_to_base64(image_path):
       with open(image_path, "rb") as image_file:
           encoded_string = base64.b64encode(image_file.read())
           return encoded_string.decode('utf-8')
           
   def stop_server_on_port(port):
       for connection in psutil.net_connections():
           if connection.laddr.port == port:
               process = psutil.Process(connection.pid)
               process.terminate()
   
   def is_comfyui_running(server_address="127.0.0.1:8188"):
   
       try:
           response = requests.get(f"http://{server_address}/", timeout=5)
           return response.status_code == 200
       except requests.RequestException:
           return False
   

4. inferless-runtime-config.yaml : This YAML file is crucial for configuring the runtime environment for our ComfyUI application on Inferless.

    build:
    system_packages:
        - "wget"
        - "ffmpeg"
        - "libgl1-mesa-glx"
    python_packages:
        - "comfy-cli==1.2.3"
        - "websocket-client==1.6.4"
        - "accelerate==0.23.0"
        - "opencv-python==4.10.0.84"
        - "boto3==1.35.9"
        - "pillow==10.4.0"
        - "torchvision==0.19.0"
        - "einops==0.8.0"
        - "transformers==4.44.2"
        - "scipy==1.14.1"
        - "torchsde==0.2.6"
        - "aiohttp==3.10.5"
        - "safetensors==0.4.4"
        - "pydantic==2.8.2"
        - "groq==0.10.0"
        - "aiohttp-sse==2.2.0"
        - "spandrel==0.3.4"
        - "kornia==0.7.3"
        - "torchaudio==2.4.0"
        - "matplotlib==3.8.0"
        - "scikit-image==0.24.0"
        - "simpleeval==0.9.13"
        - "imageio-ffmpeg==0.5.1"
        - "pypng==0.20220715.0"

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Architecture overview

Our solution utilizes a streamlined request-response model consisting of the following steps:

1. User Request: Users submit requests to the Inferless endpoint, specifying both the desired workflow and a prompt. Inferless then directs these requests to our ComfyUI server.
2. ComfyUI Processing: Upon receiving the request, the specified workflow is executed by the ComfyUI server, which processes the prompt to generate the image. Once the image is ready, we retrieve the result.
3. Response Delivery: The generated image is encoded in base64 format and returned to the user.

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Deploy your ComfyUI application

Deploying your ComfyUI application on Inferless involves a series of straightforward steps that leverage the platform’s serverless capabilities. Here’s the steps for deployment:

1. Begin by creating an NFS volume on Inferless. This volume will serve as the persistent storage for your ComfyUI files, workflows, and generated images. Note the mount path (e.g., /var/nfs-mount/YOUR_VOLUME_MOUNT_PATH) as you’ll need to pass as an environment variable as NFS_VOLUME.

2. Ensure your build.sh, app.py, comfy_utils.py, and any custom workflow JSON files are ready. These files should be uploaded to a GitHub repository for easy access during deployment.

3. Log into your Inferless account and click on the Add a custom model. Then follow these steps:

   • Select the Github from the model provider list and then select the GitHub repository URL and branch.
   • Choose the type of machine, and specify the minimum and maximum number of replicas for deploying your ComfyUI.

   • Upload the Custom Runtime and choose the NFS Volume that we have created. Secrets and set Environment variables like Inference Timeout, Container Concurrency, Scale Down Timeout.

   • Now pass the NFS Volume path and Hugging Face access token as a environment variables NFS_VOLUME as key and YOUR_VOLUME_MOUNT_PATH as the value. And then HF_ACCESS_TOKEN as key and YOUR_HF_ACCESS_TOKEN as the value.

   • Click on the deploy to start the deployment process.

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Adding your ComfyUI workflow with Example

Let’s take ComfyUI workflow for Flux as an example and import this workflow into Inferless.

1. First, download the workflow.json for the Flux workflow and convert it into a format compatible with the ComfyUI API.
2. Identifying Required Models: For the Flux workflow, we need to download the FLUX model and any other model required for this workflow. We’ll add this to our build.sh script. You can add any other models in similar way.

comfy --skip-prompt model download --url https://huggingface.co/black-forest-labs/FLUX.1-dev/resolve/main/flux1-dev.safetensors --relative-path models/unet --set-civitai-api-token $HF_ACCESS_TOKEN
comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/t5xxl_fp16.safetensors --relative-path models/clip
comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/clip_l.safetensors --relative-path models/clip
comfy --skip-prompt model download --url https://huggingface.co/comfyanonymous/flux_text_encoders/resolve/main/t5xxl_fp8_e4m3fn.safetensors --relative-path models/clip
comfy --skip-prompt model download --url https://huggingface.co/black-forest-labs/FLUX.1-schnell/resolve/main/ae.safetensors --relative-path models/vae

3. Updating Input Schema: If your Flux workflow requires additional user inputs, you will need to update the input_schema.py file accordingly. For instance, if your workflow requires both a prompt and a negative prompt, update the file to handle these inputs.

INPUT_SCHEMA = {
    "prompt": {
        'datatype': 'STRING',
        'required': True,
        'shape': [1],
        'example': ["A cat holding a sign that says hello world"]
    },
     "negative_prompt": {
        'datatype': 'STRING',
        'required': True,
        'shape': [1],
        'example': ["low quality"]
    }
}

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Running Comfy-UI on Inferless

Once your ComfyUI workflow is set up and deployed on Inferless, you can run it effortlessly through a simple API call.

1. API Endpoint: Inferless provides a unique URL for your deployed model, which will be used for making requests.

2. Authentication: Include an authorization token in the request headers. Inferless uses bearer token authentication for secure access.

3. Input Format: Format your input as a JSON object, specifying the parameters defined in your input_schema.py.

Here’s a Python example of how to make a request to your deployed ComfyUI model on Inferless:

In this example:

import requests 
import json
curl --location '<your_inference_url>' \
    --header 'Content-Type: application/json' \
    --header 'Authorization: Bearer <your_api_key>' \
URL = '<your_inference_url>'
headers = {"Content-Type": "application/json", "Authorization": "Bearer <your_api_key>"}
          
data = {
	"inputs": [
		{
			"name": "prompt",
			"shape": [
				1
			],
			"data": [
				"A cat holding a sign that says hello world"
			],
			"datatype": "BYTES"
		},
		{
			"name": "workflow",
			"shape": [
				1
			],
			"data": [
				"https://github.com/inferless/ComfyUI-Inferless-template/raw/main/workflows/sd1-5_workflow.json"
			],
			"datatype": "BYTES"
		},
        {
            "name": "negative_prompt",
            "optional": true,
            "shape": [
                1
            ],
            "data": [
                "blurry, illustration, toy, clay, low quality, flag, nasa, mission patch"
            ],
            "datatype": "BYTES"
        }
	]
} 
response = requests.post(URL, headers=headers, data=json.dumps(data)) 
print(response.json())

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Choosing Inferless for Deployment

Deploying your ComfyUI application with Inferless offers compelling advantages, making your development journey smoother and more cost-effective. Here’s why Inferless is the go-to choice:

1. Ease of Use: Forget the complexities of infrastructure management. With Inferless, you simply bring your model, and within minutes, you have a working endpoint. Deployment is hassle-free, without the need for in-depth knowledge of scaling or infrastructure maintenance.
2. Cold-start Times: Inferless’s unique load balancing ensures faster cold-starts. Expect around 10.59 seconds to process each queries, significantly faster than many traditional platforms.
3. Cost Efficiency: Inferless optimizes resource utilization, translating to lower operational costs. Here’s a simplified cost comparison:

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Scenario 1

You are looking to deploy a ComfyUI application for processing 100 queries.

Parameters:

• Total number of queries: 100 daily.
• Inference Time: All models are hypothetically deployed on A100 80GB, taking 10.59 seconds of processing time and a cold start overhead of 6.88 seconds.
• Scale Down Timeout: Uniformly 60 seconds across all platforms, except Hugging Face, which requires a minimum of 15 minutes. This is assumed to happen 100 times a day.

Key Computations:

1. Inference Duration: Processing 100 queries and each takes 10.59 seconds Total: 100 x 10.59 = 1059 seconds (or approximately 0.29 hours)
2. Idle Timeout Duration: Post-processing idle time before scaling down: (60 seconds - 10.59 seconds) x 100 = 4941 seconds (or 1.37 hours approximately)
3. Cold Start Overhead: Total: 100 x 6.88 = 688 seconds (or 0.19 hours approximately)

Total Billable Hours with Inferless: 0.29 (inference duration) + 1.37 (idle time) + 0.19 (cold start overhead) = 1.85 hours

Total Billable Hours with Inferless: 1.85 hours

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Scenario 2

You are looking to deploy a ComfyUI application for processing 1000 queries per day.

Key Computations:

1. Inference Duration: Processing 1000 queries and each takes 10.59 seconds Total: 1000 x 10.59 = 10590 seconds (or approximately 2.94 hours)
2. Idle Timeout Duration: Post-processing idle time before scaling down: (60 seconds - 10.59 seconds) x 100 = 4941 seconds (or 1.37 hours approximately)
3. Cold Start Overhead: Total: 100 x 6.88 = 688 seconds (or 0.19 hours approximately)

Total Billable Hours with Inferless: 2.94 (inference duration) + 1.37 (idle time) + 0.19 (cold start overhead) = 4.5 hours

Total Billable Hours with Inferless: 4.5 hours

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Pricing Comparison for all the Scenario

By opting for Inferless, you can achieve up to 80.94% cost savings.

Please note that we have utilized the A100(80 GB) GPU for model benchmarking purposes, while for pricing comparison, we referenced the A10G GPU price from both platforms. This is due to the unavailability of the A100 GPU in SageMaker.

Also, the above analysis is based on a smaller-scale scenario for demonstration purposes. Should the scale increase tenfold, traditional cloud services might require maintaining 2-4 GPUs constantly active to manage peak loads efficiently. In contrast, Inferless, with its dynamic scaling capabilities, adeptly adjusts to fluctuating demand without the need for continuously running hardware.

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Conclusion

By following this approach, you can easily integrate your ComfyUI workflows into other applications or scripts, leveraging the power of Inferless for efficient and scalable AI image generation.