Google Calendar Token Credential Error

Questions
1

I’m facing an issue while trying to set up Google OAuth2 credentials in n8n.

Setup Details:

  • I’m self-hosting the latest n8n Docker image on AWS EC2 instance
  • Im using a custom domain from namecheap.
  • I’ve followed the official documentation and multiple tutorials to set up Google OAuth2 credentials.
  • My OAuth Redirect URL in the Google Cloud Console is set to:
    (http://localhost:5678/rest/oauth2-credential/callback)

The Problem

When I enter my Client ID and Client Secret in the n8n Google Calendar OAuth2 API node and proceed to sign in to my Google account, I:

  1. Select my Google account.
  2. Grant all the required permissions.
  3. Click “Allow.”

I’m taken to a page with the following error:
This site can’t be reached localhost refused to connect. ERR_CONNECTION_REFUSED

Screenshot from 2025-06-26 11-28-37
Screenshot from 2025-06-26 11-28-37626×940 42.7 KB

2

Yeah can not use localhost as redirect domain url.

Need to use ngrok or cloudflare tunnel to get a public accessible domain.

3

CAUSE

I have a domain setup but my docker env’s Webhook_URL was set to localhost:5678

SOLUTION

  1. Print your container env to check your webhook url
    sudo docker exec -it <container_name_or_id> printenv
  2. If it isnt https://[domainname].com
    sudo docker stop [container_name]
    sudo docker rm n8n
  3. Replace the old one
sudo docker run -d \
  --name n8n \
  -e N8N_HOST=[domain] \
  -e N8N_PORT=5678 \
  -e WEBHOOK_URL=https://[domain].com \
  -e N8N_SECURE_COOKIE=false \
  -v n8n_data:/home/node/.n8n \
  -p 5678:5678 \
  n8nio/n8n

Add a google credential. The callback url should be

https://[domain]/rest/oauth2-credential/callback