Unable to Trigger n8n Webhook with POST Request from Flowise

Questions
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1

Hi n8n Community,

I’m currently encountering an issue while trying to trigger an n8n webhook using a POST request sent via the Flowise tool. Despite setting everything up correctly, the webhook doesn’t seem to receive or respond to the POST requests sent from Flowise.

Here’s a detailed summary of my setup and steps taken:

1. Webhook Setup in n8n:

  • I’ve created a webhook node in n8n and set it to listen for POST requests.
  • The webhook URL is hosted on my n8n cloud instance and follows the structure:

bash

Copy code

https://your-n8n-instance/webhook-test/webhook
  • When tested using Postman or similar tools, the webhook works perfectly and responds as expected with a 200 status code and the message:

json

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{ "message": "Workflow was started" }

2. Flowise Setup:

  • I’m using Flowise to trigger the webhook via the fetch method in a custom tool. The code snippet for the POST request is as follows:

javascript

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const fetch = require('node-fetch');
const url = 'https://your-n8n-instance/webhook-test/webhook';

const options = {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ query: "indexes" }),
};

try {
    const response = await fetch(url, options);
    const text = await response.text();
    console.log('Response from n8n:', text);
} catch (error) {
    console.error('Error:', error.message);
}
  • The request does not throw any errors in Flowise, but the n8n webhook is not triggered. I don’t see any logs or events in n8n indicating that the webhook received the request.

3. Debugging Steps Taken:

  • Tested the webhook using Postman, and it works as expected.
  • Verified the URL and headers are correct.
  • Ensured the request payload ({ "query": "indexes" }) is being sent in the correct JSON format.
  • Confirmed there are no network or firewall restrictions preventing the request.
  • Observed that the issue persists only when the request is sent from Flowise.

Question:

Could this be an issue with how Flowise sends POST requests to n8n? Are there any known limitations or specific configurations required for webhook compatibility with Flowise?

Any guidance or suggestions for troubleshooting would be greatly appreciated!

Thank you in advance!

2

It looks like your topic is missing some important information. Could you provide the following if applicable.

  • n8n version:
  • Database (default: SQLite):
  • n8n EXECUTIONS_PROCESS setting (default: own, main):
  • Running n8n via (Docker, npm, n8n cloud, desktop app):
  • Operating system:
3

Welcome to the community @Yashal_Ali !

Tip for sharing information

Pasting your n8n workflow

Ensure to copy your n8n workflow and paste it in the code block, that is in between the pairs of triple backticks, which also could be achieved by clicking </> (preformatted text) in the editor and pasting in your workflow.

```
<your workflow>
```

That implies to any JSON output you would like to share with us.

Make sure that you have removed any sensitive information from your workflow and include dummy or pinned data with it!

There should be no difference from where you send HTTP request from. Perhaps you need to whitelist n8n IPs on Flowise side (I’m not familar with that service), Cloud IP addresses | n8n Docs.

Just a reminder, that for the test URL to work you need to activate it manually and it stays active for a short period of time. Maybe try production mode instead and send the request to production URL (which is different from test URL, Webhook node documentation | n8n Docs).

You also might want to test your Flowise code sening the POST request to some “bin” webhook to ensure it does send the HTTP request in the first place. Try Webhook.site - Test, transform and automate Web requests and emails, for example.

4

I am using (n8n.io - Workflow Automation).
execution process = default
operating system = windows