Caching with PSRs at PHP Tour

In this talk you will learn what PSR-6 and PSR-16 are, why they are designed like they are, what the differences are, and how to use them. From the provided interfaces, the virtual package on Packagist.org, to the implementations available. Everything will be explained for both beginners and more experienced developers. We will dive into implementations, cache stampede protection, all using libraries we can find on Packagist.org. We will also show how to start using it today in our current applications by using adapters. The entire talk will be accompanied with code samples and live demos, showing both working and failing caching systems.

Transcript

1. Caching with PSRs PHP Tour Montpellier #phptour @hannesvdvreken
2. Hi, my name is Hannes.
3. Caching PSRs Caching in PHP anno 2018
4. 1. Intro 2. Caching in 2015 3. Hello PSR-6 4. Hello PSR-16
5. 1. Intro what is caching?
6. WHAT IS CACHING Speeding up your app
7. WHAT IS CACHING 1. Query stored value 2.Execute slow task 3.Remember result
8. WHAT IS CACHING Should not cause app failure
9. WHAT IS CACHING - EXAMPLES • HTTP Request • Slow DB call • Process image/zip/…
10. WHAT IS CACHING Should not cause app failure
11. WHAT IS CACHING geocode IP check cache store result check cache
12. WHAT IS CACHING Should not cause app failure
13. WHAT IS CACHING At different layers: User-Agent Webserver (Varnish/Nginx) Application Opcache
14. WHAT IS CACHING Should not cause app failure
15. WHAT IS CACHING • cache busting • TTL • warming up
16. 2. Caching in 2015 the state of caching (pre PSR-FIG)
17. APPLICATION CACHING IN 2015 1. Libraries do it 2.Frameworks do it 3.Cache libs do it
18. APPLICATION CACHING IN 2015 Frameworks & cache libs have their own: - set of supported caching back- ends - maybe an interface to allow custom implementations
19. APPLICATION CACHING IN 2015 Adapters everywhere!
20. APPLICATION CACHING IN 2015 Framework X cache Framework Y cache Package W cache Cache package Z Adapter W->X Adapter W->Y Adapter W->Z Adapter Y->Z
21. APPLICATION CACHING IN 2015 If no adapter available - Write your own - Store in different cache stores
 (ops will not love you for that)
22. 3. Hello PSR-6
23. INTRODUCING PSR-6 Finalized & accepted in December 2015
24. INTRODUCING PSR-6 Repository - Entity
25. INTRODUCING PSR-6 use Psr\Cache\CacheItemPoolInterface; use Psr\Cache\CacheItemInterface; $item = $pool->getItem($key); $item->getKey(); $item->get();
26. INTRODUCING PSR-6 Item is an entity, it’s not immutable, but the Key is
27. INTRODUCING PSR-6 Don’t instantiate your own Items. $item = $pool->getItem(‘key’) ->set($value) ->expiresAfter(3600); $pool->save($item);
28. INTRODUCING PSR-6 Pool has support for multi-actions $pool->getItems($keys); $pool->saveDeferred($item); $pool->commit();
29. INTRODUCING PSR-6 Repository - Entity model allows extensions
30. INTRODUCING PSR-6 Allows future specced features by reserving characters - {}()/\@:
31. INTRODUCING PSR-6 Cache features: - Stampede protection: Parallel incoming requests executing long process to update cache value
32. STAMPEDE PROTECTION
33. STAMPEDE PROTECTION
34. STAMPEDE PROTECTION
35. STAMPEDE PROTECTION
36. STAMPEDE PROTECTION
37. STAMPEDE PROTECTION
38. STAMPEDE PROTECTION
39. STAMPEDE PROTECTION
40. STAMPEDE PROTECTION
41. INTRODUCING PSR-6 Cache features: - Stampede protection - Taggable cache cache/taggable-cache
42. INTRODUCING PSR-6 Cache features: - Stampede protection - Taggable cache $item->setTags([‘cat-1']); $pool->invalidateTags([‘cat-1’]);
43. INTRODUCING PSR-6 Cache features: - Stampede protection - Taggable cache - Hierarchical cache cache/hierarchical-cache
44. INTRODUCING PSR-6 Cache features: - Stampede protection - Taggable cache - Hierarchical cache $pool->hasItem('|users|4711|followers'); // true $pool->delete(‘|users|4711'); $pool->hasItem('|users|4711|followers'); // false
45. Practical who uses it, and how can I use it?
49. START USING IT Integration tests for implementations: cache/integration-tests
51. START USING IT class PoolIntegrationTest extends CachePoolTest { public function createCachePool() { return new MyCustomCachePool(); } }
52. START USING IT cache/taggable-cache cache/namespaced-cache cache/hierarchical-cache cache/chain-adapter cache/array-adapter cache/void-adapter cache/prefix-adapter
53. START USING IT - UPGRADE Upgrade paths
54. START USING IT - UPGRADE Libraries
55. START USING IT - UPGRADE Libraries (next major versions) have a PSR-6 caching decorator
56. START USING IT - UPGRADE Frameworks
57. START USING IT - UPGRADE Start using PSR-6 enabled libraries with adapters for current FW’s implementation.
58. START USING IT - UPGRADE Example: symfony/cache cache/illuminate-adapter
59. START USING IT Adoption?
61. 4. Hello PSR-16
62. INTRODUCING PSR-16 Finalised & accepted in December 2016
63. One simple interface INTRODUCING PSR-16
64. Psr\SimpleCache\CacheInterface INTRODUCING PSR-16
65. // Returns null when not available. // Returns null when you set it to null. $cache->set($key, null); $value = $cache->get($key); // null INTRODUCING PSR-16
66. $cache->set($key, new ValueObject()); INTRODUCING PSR-16
67. CacheInterface::getMultiple CacheInterface::setMultiple CacheInterface::deleteMultiple INTRODUCING PSR-16
68. Differences from PSR-6 - No `null` values - No deferring INTRODUCING PSR-16
69. Also allows future extension thanks to reservation of characters - {}()/\@: INTRODUCING PSR-16
70. Practical who uses it, and how can I use it?
73. START USING IT Upgrade path? Same as PSR-6
74. START USING IT Adoption?
78. $laravelCache = App::make(‘cache’); $psr6Cache = new IlluminateCachePool($laravelCache); $psr16Cache = new SimpleCacheBridge($psr6Cache); INTRODUCING PSR-16
79. 1. Intro 2. Caching in 2015 3. Hello PSR-6 4. Hello PSR-16 RECAP
80. Thank you! #phptour @hannesvdvreken
81. Time for questions! #phptour @hannesvdvreken