Generate AI Images in n8n with Fal Flux HTTP Requests

Opening Problem Statement

Meet Sarah, a freelance graphic designer juggling multiple client projects every week. She spends countless hours manually generating high-quality images for her clients using AI tools, repeatedly copying prompts, submitting requests, and downloading images. The process is tedious, taking away valuable time she could spend on creative design and client communication. Sarah also faces delays from manual checking of image generation statuses and the risk of losing track of files saved in multiple locations.

This inefficiency not only causes frustration but also costs her billable hours and potentially impacts client satisfaction due to delays. How can Sarah automate this entire AI image generation workflow efficiently and reliably?

What This Automation Does

This specific n8n workflow streamlines the process of AI image generation using Fal Flux’s API with HTTP Request nodes and automation steps to manage the entire lifecycle from prompt input to image storage.

• Accepts configurable prompts and image parameters (width, height, inference steps, guidance scale)
• Submits image generation requests automatically via HTTP POST to Fal Flux’s AI image service
• Polls the status of image generation with timed waits and HTTP GET requests to ensure completion
• Fetches the final generated image URL once ready
• Downloads the image directly from the URL
• Uploads and organizes the downloaded image to a designated Google Drive folder

This automation removes hours of manual work: no more submitting repetitive requests, manually polling status, or downloading and organizing images. It ensures a smooth, hands-off generation and storage process.

Prerequisites ⚙️

• n8n Account with workflow automation access 🔌
• Fal Flux API account with API key for HTTP Header Authentication 🔐
• Google Drive account with OAuth2 credentials for file upload 📁

Optional: If you prefer more control and privacy, you can self-host n8n as per guides available at resources like Hostinger’s n8n hosting.

Step-by-Step Guide

1. Trigger the workflow with Manual Trigger

From the n8n editor, start by adding the Manual Trigger node named “When clicking ‘Test workflow’”. This lets you manually start the workflow to test and run it step-by-step.

Navigate to the Nodes panel → Add → Manual Trigger → Renamed it accordingly. This node doesn’t require configuration.

Successful output: The workflow waits for your manual start command.

Common mistake: Forgetting to activate the workflow or trigger the manual start.

2. Set Input Parameters with the Set Node

Add the Set node named “Edit Fields” connected to the manual trigger. Here, configure the image prompt and generation parameters the workflow uses.

Navigate: Add Node → Set → Rename “Edit Fields” → Click on “Values to Set” → Add the following fields:

Prompt: Thai young woman net idol 25 yrs old, walking on the street
Width: 1024
Height: 768
Steps: 30
Guidance: 3.5

This sets the AI image generation parameters programmatically.

Expected output: These parameters flow downstream to the next nodes.

Common mistake: Typo in JSON fields leads to failed API calls.

3. Submit the Image Generation Request (Fal Flux HTTP Request)

Add the HTTP Request node named “Fal Flux” connected to “Edit Fields”. It sends a POST request to Fal Flux’s Flux.dev API endpoint.

Configure:

• Method: POST
• URL: https://queue.fal.run/fal-ai/flux/dev
• Body Type: JSON
• JSON Body with variables:

{
 "prompt": "{{ $json.Prompt }}",
 "image_size": { "width": {{ $json.Width }}, "height": {{ $json.Height }} },
 "num_inference_steps": {{ $json.Steps }},
 "guidance_scale": {{ $json.Guidance }},
 "num_images": 1,
 "enable_safety_checker": true
}

Set authentication with your Fal Flux API key using generic HTTP Header Auth.

Expected output: Receives a request_id in the response to track the image generation.

Common mistake: Missing or incorrect API key causing 401 Unauthorized.

4. Wait 3 Seconds Before Polling Status

Add the Wait node named “Wait 3 Sec” connected to “Fal Flux” node. This adds a pause to let the AI server start processing.

Configuration: Set to 3 seconds.

Expected output: Workflow pauses before status check.

Common mistake: Skipping wait can cause premature status requests and errors.

5. Poll the Status (Fal Flux HTTP GET Request)

Add an HTTP Request node named “Check Status” connected to “Wait 3 Sec” to query the request status.

Configure:

• Method: GET
• URL: https://queue.fal.run/fal-ai/flux/requests/{{ $json.request_id }}/status
• Authorization: Header Auth with Fal Flux API key

Expected output: JSON response showing status such as “COMPLETED” or “PROCESSING”.

Common mistake: Incorrect URL path or missing request_id variable causes 404 errors.

6. Conditional Check If Generation is Completed

Add an IF node named “Completed?” connected to “Check Status” node. It checks if the status equals “COMPLETED”.

Configure the condition: status equals COMPLETED.

Expected outcome: If yes, continue to fetch the image URL; if not, loop back to wait and check again.

Common mistake: Mismatched case sensitivity in status string.

7. Loop Until Completed: Wait and Status Check

Connect the “Completed?” node’s false output back to the “Wait 3 Sec” node to repeat polling every 3 seconds until completion.

This looping ensures the workflow patiently waits for image generation to finish.

Expected outcome: Successful completion leads to the next step.

8. Get Image Result URL

Once completed, follow the true output of “Completed?” to the HTTP Request node “Get Image Result URL” which calls:

GET https://queue.fal.run/fal-ai/flux/requests/{{ $json.request_id }}

This fetches the image’s metadata and URL.

Expected output: Response includes the image URL in JSON.

9. Download the Actual Image

Connect “Get Image Result URL” node to an HTTP Request node “Download Image” that requests the image URL directly:

URL: {{ $json.images[0].url }}

Expected output: Binary image data ready for upload.

10. Save Image to Google Drive

Finally, connect “Download Image” node to the Google Drive node.

Configure Google Drive node:

• Set Drive Id to “My Drive”
• Folder Id to your target folder (e.g., “Flux Image” folder ID)
• Name field set to {{$binary.data.fileName}}
• Authenticate with Google Drive OAuth2 API

Expected outcome: Image file saved into your Google Drive folder.

Customizations ✏️

• Change Image Prompt and Size: Modify fields in the “Edit Fields” node to personalize the AI prompt, width, height, steps, and guidance scale.
• Adjust Polling Interval: Change the “Wait 3 Sec” node duration to faster or slower polling depending on your API limits or preference.
• Save to Different Storage: Replace the Google Drive node with other storage integrations like Dropbox or AWS S3 if supported by n8n.
• Add Image Variations: Modify JSON body in the “Fal Flux” node to increase “num_images” for multiple image generation per request.

Troubleshooting 🔧

• Problem: “401 Unauthorized” when submitting image generation request.
  Cause: Incorrect or missing API key in HTTP Header Auth.
  Solution: Double-check Fal Flux API key in credentials, ensure header name “Authorization” is exactly set with “Key YOUR_API_KEY” format.
• Problem: Workflow gets stuck in infinite waiting loop.
  Cause: Status never changes to “COMPLETED” due to API delays or errors.
  Solution: Add a timeout condition in “Completed?” node or add max retry node to break loop after set attempts.
• Problem: Image file not appearing in Google Drive.
  Cause: Incorrect folder ID or insufficient permissions.
  Solution: Verify the Google folder ID, ensure credentials allow file upload, and test with manual uploads.

Pre-Production Checklist ✅

• Confirm Fal Flux API key is set and authenticated in n8n credentials.
• Verify Google Drive credentials and folder ID for write access.
• Fill “Edit Fields” node with valid prompt and parameters.
• Test manual trigger to ensure the workflow runs end-to-end without errors.

Deployment Guide

Activate your workflow by toggling the active switch in n8n. Run manual tests after deployment. Monitor workflow executions in n8n’s executions list for errors or API failures.

Set up alerts or logs for key failure points, especially HTTP request failures, to ensure reliability in production.

FAQs

• Can I use a different AI image generation API?
  Yes, but you will need to adjust HTTP Request node URLs, request body formats, and authentication accordingly.
• Does this workflow consume API credits?
  Yes, each image generation request consumes Fal Flux API usage credits based on their pricing.
• Is my data safe?
  The workflow uses secure header authentication and connects only to trusted APIs, but always review credential management best practices.
• Can this workflow handle multiple images at once?
  Currently, it is configured for single image generation per request, but you can customize the “num_images” parameter to handle multiple.

Conclusion

By following this detailed n8n automation guide, you have built a reliable system to generate AI images using the Fal Flux API, automatically handling prompt submission, status polling, image downloading, and organized storage to Google Drive. This solution saves you hours of manual work and improves your productivity.

Next, you could enhance this workflow by integrating notifications (e.g., email or Slack) when images are ready or adding a front-end form for easier prompt inputs.

With this setup, Sarah and others in creative fields can focus on what they love—designing—while n8n handles the repetitive parts seamlessly.