Varnish is used extensively within Amedia's microservices architecture to cache APIs and content. It caches Amedia's public read-only REST API that serves over 100,000 articles daily from multiple content management systems. Cache invalidation is challenging with a microservices architecture but they address it with techniques like purging by URL path or using Varnish's cache channel feature to invalidate groups of URLs.

1. How Amedia uses Varnish within the Microservices
architecture.
Varnish everywhere…
1

2. How Amedia does API caching
with Varnish
2

3. 3
Simen Graff Jenssen
Head of Infrastructure
@simengj
simen.graff.jenssen@amedia.no
Jakob Vad Nielsen
Senior Developer
@jakobvad
jakob.nielsen@amedia.no

4. 4
77 publications
1,850 new articles published every day
5,721,352 articles in our databases/CMSs
6,660,559 images
110,000 different articles served online every day
940 journalists and 140 editors

5. ESI and Cache-Channel
support in Varnish 2
5

6. 6

7. So, Microservices…
7
a particular way of designing software applications as
suites of independently deployable services

8. 8
STATELESS
STATELESS
STATELESS
STATELESS
Http
Html
XML/JSON

9. Varnish for API caching
since 2008
9

10. ACP
Amedia Content Platform

11. 11

12. 12
Escenic 4 PolopolyEscenic 5 Arkena
ACP Composer (Public Read Only Rest API)

13. 13
Escenic 4 PolopolyEscenic 5 Arkena
ACP Composer (Public Read Only Rest API)

14. 14
Arkena
Escenic 5
Escenic 4

15. Cache invalidation
15
The hard part:

16. 16
ACP Composer (Public Read Only Rest API)
Escenic 4 PolopolyEscenic 5 Arkena

17. 17
Escenic 5
Atomizer
purge /bar
Cache-Control: channel-maxage=1000, group=/foo, group=/bar, group=/zot
Cache-Control: channel-maxage=5000, group=/bar
varnish-cc

18. Thank you!
18