S3 buckets containing periods not allowed

So, with the introduction of the s3_cdn_url setting, you can set a custom URL to be used instead of the long S3 URL.

Unfortunately, s3_upload_bucket doesn’t allow periods in the name… which means that if I, as per Amazon’s documentation, create a bucket called static.example.com and point a CNAME to it, I can set Discourse to print out URLs to static.example.com, but I can’t set it to actually upload to that bucket.

(I want to put Cloudflare in front of a CNAME, making for a low-cost but effective CDN. It’s not just for looks.)

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If periods are indeed supported we should relax the restriction … @techAPJ can you have a quick look

As I understood it, periods in the bucket name cause havoc with https and certificates so it is strongly discouraged that you do this. Unless you never plan to use https.


We ran into many problems with this, which is why it is disallowed. It is not random. It’s a resolution to a problem many Discourse instances faced.


aha … well then let’s just leave it as is for now.

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This is a good point. However, I think it should be downgraded to a warning, rather than being outright forbidden.

While locking yourself out of HTTPS is a terrible idea on its own, both Amazon CloudFront and CloudFlare (off the top of my head) offer SNI-based SSL certificates that can be put in front of a bucket, even if the default certificate would no longer cover it.

CloudFront can be configured to pull from an S3 bucket of your choice (even if it’s named something different), but also costs money. Well invested money, one may argue, but money nonetheless. If one does not need the additional functionality of a full-fledged CDN, CloudFront is a slightly overkill solution to the problem of “I want my forum to load faster”.
(An incredibly convoluted pricing model doesn’t help… I think there’s an XKCD for this, but I can’t find it.)

CloudFlare is not as configurable, but also offer quite a few other features as well - as well as the very approachable price tag of free. With a properly named bucket and a DNS rule (possibly supplemented by some caching rules), you get an instant improvement to loading performance, with no downsides whatsoever.
Perhaps not as big of a difference as a full CDN would make, but hey, it’s free performance.


@codinghorror @sam I am using a cloudflare CDN to access the S3 content (where discourse uploads all the files) and not directly.

s3 mandates to use bucket name like files.discourse.org to access its content through cname files


Is there a way to allow periods in the S3 name (may be with a warning for https issue for direct s3 use). This is a showstopper in my case to use S3 with cloudflare and discourse.


We worked around that here @gingerman :


@fearlessfrog Thanks…I ended up doing exactly the same. I don’t know how I missed your thread earlier. Just to highlight - this approach has a limitation in terms of cache invalidation. we have to do separately invalidations in cloudfront and cloudflare (after rebaking posts). It would be great to automate them with a script at the very least.

I hit up on the same blocks eventually in terms of optimised image urls and was planning to start a thread today…Nice to know that you have already helped the team towards a fix in the below given thread. Kudos for that.