Hi, i have been use a webhook for a post request. But the app (UI Bakery made) gives me these error: 0 Unknown Error. This could be a CORS issue - try configuring your server to allow requests enable cross-origin resource sharing Access Control Allow Header is set. What can it be ? Thanks, Stef…

Jan, when you use the Docker Version. You need this parameter in Docker Compose traefik.frontend.headers.customResponseHeaders=Access-Control-Allow-Origin:* Then it works ! Thanks, Stefan

Hey @Stefan , When others have run into this in the past, the solution was to run everything behind a proxy, which, in my opinion, is the right way to do this anyway. You are simply asking for trouble if you are running n8n “naked” on the internet.

[image] Tephlon: everything behind a proxy, which, in my opinion, is the right way to do this anyway. You are simply asking for trouble if you are running n8n “naked” on the internet. Ok ? I use your Docker Version, this runs behind a proxy ? Right ?

If you run n8n with docker then there will just be n8n and no proxy. If you use run n8n as described in our Server Setup Guide then there will be a proxy in front of it. In this case traefik. About your CORS issue. Did you try to make a request with curl to see if the Access Control Allow Header g…

I had to add a few more labels to my docker: - traefik.http.middlewares.cors.headers.customResponseHeaders.Access-Control-Allow-Origin=* - traefik.http.middlewares.cors.headers.customResponseHeaders.Access-Control-Allow-Methods=GET, POST, OPTIONS - traefik.http.middlewares.cors.he…

Thank you for this, it made my problems with CORS go away immediately as well! A question regarding security though since I feel I need to learn, what exactly does it mean to remove f.e. the Access-Control-Allow-Origin from the proxy? Doesn’t this remove the whole purpose with a proxy? On the other…

@JulioC_me Man, you made my day. For the whole day I tried to solve that. And only your advice helped

CORS Error

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jan August 26, 2020, 4:28pm 6

Interesting. But it should also work if you set it as a response header an the Webhook-Node. At least in our setup it is working fine. Can not imagine that traefik would remove that.

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