This repo is our simple heroku deployment of jake.pubpub.org.
Jake is our server which runs Thumbor for resizing and editing images on the fly.
PubPub assets are named with the following convention
/hash/timestamp.extension
The hash is a 8 character hex string. This hash is simply a pseudo-random string that allows certain performance and scalability optimizations for S3 (and likely other storage infrastructures).
The timestamp is a unix timestamp with milliseconds (i.e. new Date().getTime()).
Our assets infrastucture has two main components: an 'originals' fileserver, and a resizing service.
The originals fileserver:
DNS + CDN (Cloudflare)
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CDN (CloudFront)
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assets.pubpub.org (CNAME)
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fileserver (S3)
The resizing service:
CDN (Cloudflare)
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jake.pubpub.org
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Thumbor
The originals fileserver is behind two layers of CDN because S3 alone does not provide what's needed to have a custom domain with SSL. That is, we can't make https://assets.pubpub.org work without using the SSL provided by Cloudfront. Cloudflare in this case behaves more or less as a DNS provider allowing us to CNAME assets.pubpub.org to our Cloudflare URL. The added layer of CDN doesn't hurt anything.
heroku create
heroku buildpacks:set heroku/python
heroku buildpacks:add https://github.com/jc4p/heroku-buildpack-gifsicle.git
git push heroku master
heroku scale web=1
Herokus cache seems to fail with gifsicle on each new build (the original build works fine).
To clear the Heroku cache:
heroku repo:purge_cache -a <app-name>