Can't upload to S3 (Cloudflare R2)

[darkpixlz (Pyx)]

I was setting up R2 on my site following some guides here but no I just see a generic Sorry, but your upload failed. Please try again. message when I try to upload a file. The only thing I see in the logs are this:

I have my URLs configured in the app.yml file because the web UI was rejecting my URLs as structured in the how-to posts (invalid format):

The CDN_URL is the custom domain (as set in Cloudflare) and the S3_ENDPOINT is the URL in the web panel. I have all of my options configured properly with correctly created auth tokens:

It looks like Cloudflare is seeing some requests but nothing is being stored.

What is the problem?

[David_Ghost]

Hey,

Is it not because of the final slashs (/) in the s3 cdn url and the s3 endpoint?

[Lilly (Lillian)]

are these the guides you followed? are you certain your upload bucket is named “discourse”?

Configure an S3 compatible object storage provider for uploads

This topic covers how to configure some common S3 compatible Object Storage providers (S3 clones). See Set up file and image uploads to S3 for more details about Amazon AWS S3 configuration, which is officially supported and used internally by Discourse for our hosting services. Provider Service Name Works with Discourse? Amazon AWS S3 Yes Digital Ocean Spaces Yes Linode Object Storage Yes Google Cloud Storage Yes Scaleway Object Storage Yes Vultr Obj…

Using Discourse with Cloudflare: Best Practices

Using Discourse with Cloudflare This guide explains how to configure and use Discourse with Cloudflare, including security best practices and troubleshooting tips. Required user level: Administrator Console access is required for self-hosted installations Summary Cloudflare can enhance your Discourse instance with improved performance through CDN, additional security layers like DDoS protection, and HTTPS support. This guide covers the…

yea if you remove the ending slashes you should be able to use those URLs in the UI settings.

[darkpixlz (Pyx)]

@Lilly

are these the guides you followed

Yes, the first one is what I followed

@Lilly

are you certain your upload bucket is named “discourse”?

Correct

I’ll try removing the slashes and will follow up

[darkpixlz (Pyx)]

I removed the trailing slashes, still no luck. Same Unauthorized error.

Token is configured properly too

[Lilly (Lillian)]

are you certain the cloudflare R2 token has read/write permission and did you correctly configure the CORS policy? i know you have a bit of a unique server configuration, and the cloudflare bucket permissions and configuration need to be exactly correct or it will throw permissions errors.

[Lilly (Lillian)]

@darkpixlz

Token is configured properly too

you created the wrong token type - you have a general API token. you need to create an R2 bucket token:

1. go to the cloudflare dashboard → R2 object storage (left sidebar under storage & databases).
2. on the right side of the R2 overview page, click manage R2 API tokens.
3. click create API token.
4. set Permissions to object read & write then save
5. this will output an access key id and a secret access key. those are what you need to put into discourse’s S3 configuration

and yes you need to remove trailing slashes because discourse will likely reject them

[darkpixlz (Pyx)]

Thanks, turns out that was the problem.. needlessly confusing but that’s Cloudflare’s fault

[Lilly (Lillian)]

yea the cloudflare dashboard can be a hornet’s nest of configuration lol. glad you got it fixed!