HHVM/Hack ShapeとTypeAssertで堅実なアプリケーション

HHVM/Hack勉強会Vol.1 slide
https://istyle.connpass.com/event/80398/

Transcript

1. shapeͱTypeAssertͰ ݎ࿚ͳΞϓϦέʔγϣϯ yuuki takezawa (ytake)
2. εϥΠυͰར༻͍ͯ͠Δαϯϓϧίʔυ https://github.com/istyle-inc/example-hack- strict-api
3. <?hh ෆ࣮֬ͳAPI
4. Ͳ͏΍ͬͯܕΛࢦఆ͢Δ͔ • Collection (Map, Vector etc) • Generics • shape • tuple
5. [ ‘message’ => ‘hackstudy’, ‘date’ => ‘2018/04/20’ ];
6. ഑ྻ͸อূ͞ΕΔ͔ • ͍ΘΏΔPHPͷ഑ྻ͸ɺܕͷ੍໿͕ͳ͍
 ࣗ༝ͳϋογϡςʔϒϧ • ഑ྻͰ͋Ε͹serialize -> json response • messageʹint͕ೖͬͨΒʁ • date͕intͩͬͨΒʁ • Ωʔ͕૿͑ͨΓݮͬͨΓ • typo?
7. ෆ࣮֬Ͱ͔͠ͳ͍ʂ
8. <?hh shape
9. shape( 'message' => string, 'date' => string, );
10. <?hh // strict class Serialize { public function execute(shape( 'message' => string, 'date' => string, ) $shape): string { return serialize($shape); } }
11. $serialize = new \Serialize(); $serialize->execute(shape( 'message' => 'hackstudy', 'date' => '2018/04/20', ));
12. shapeΛ౉ͯ͠΋େৎ෉ • ഑ྻͱಉ౳ʹར༻͢Δ͜ͱ͕Ͱ͖ΔͷͰɺ
 ઃఆ஋ͳͲΛ౉͢ɺ֎෦Ϧιʔεʹର੍ͯ͠໿Λ͔͚Δ ͳͲʹ༻్ʹόονϦ • foreach͸shapeʹର࣮ͯ͠ߦͰ͖ͳ͍ • it doesn't implement Traversable or Container. • []͸࢖͑·ͤΜ • toArrayͰม׵ͯ͠΋ྑ͍
13. foreach͍ͨ͠ΜͰ͚͢Ͳ
14. <?hh shape + Collection
15. type CollectableShape = shape( 'id' => int, 'name' => string, );
16. public function executeCollection(shape( 'message' => string, 'date' => string, 'tables' => Vector<CollectableShape>, ) $shape): string { $v = Shapes::idx($shape, 'tables', Vector{ }); return serialize( array_merge( Shapes::toArray($shape), ['tables' => $v->toArray()] ) ); }
17. CollectionΛ૊Έ߹Θͤͯଟछଟ༷ʹ • ഑ྻʹม׵ͨ͠Γɺ΋͘͠͸഑ྻΛදݱͨ͠Γ • ৭ʑͳ༻్Ͱ৭ʑ੍໿Λ͔͚Δ͜ͱ͕Ͱ͖Δ • Ͱ΋shape
18. ֎෦Ϧιʔε͸shapeͰ͸ͳ͍
19. function nullthrows<T>( ?T $data, string $message = 'unexpected null’ ): T { invariant( $data !== null, $message, ); return $data; }
20. APIͷ໭Γ஋ͷνΣοΫʁ • ഑ྻʹม׵ͨ͋͠ͱʹgenerics+invariant͢Δʁ • ҰͭҰͭεΩϟϯʁ
21. hhvm/type-assert
22. ෆ࣮֬ͳ஋ΛΞαʔτʂ • primitiveܕ͸΋ͪΖΜɺmapͳͲʹ΋ • is_aͳͲ΋ந৅Խ • Ұ൪ͷ໨ۄ͸ matches_type_structure
23. <?hh // strict use namespace Facebook\TypeAssert; class Foo { const type TAPIResponse = shape( 'id' => int, 'user' => string, 'data' => shape(/* ... */), ); public static function getAPIResponse(): self::TAPIResponse { $json_string = file_get_contents('https://api.example.com'); $array = json_decode($json_string, /* associative = */ true); return TypeAssert\matches_type_structure( type_structure(self::class, 'TAPIResponse'), $array, ); } }
24. matches_type_structure • ReflectionTypeAlias ΫϥεͷgetTypeStructureϝιου͸഑ྻΛ ฦͨ͢Ίਏ͍(HackͳΒجຊstirctͰॻ͘͜ͱ͕ଟ͍)
 https://github.com/facebook/hhvm/blob/master/hphp/hack/hhi/ reflection.hhi#L308 • ܕ௨ΓͩͬͨΒͦͷ··௨աͯ͠ཉ͍͠ͷͰɺ
 Genericsʹͯ͠΄͍͠ʂ
 type_structure ؔ਺ར༻ͷΈରԠ
 https://github.com/facebook/hhvm/blob/master/hphp/hack/hhi/ typestructure.hhi#L94
25. matches_type_structure • ݕࠪ͢Δܕ͸const stringͰ͋Δඞཁ͕͋ΔͷͰɺ
 ಈతʹੜ੒͸Ͱ͖ͳ͍
 • shapeͰͻͨ͢Βॻ͔͘͠ͳ͍

26. json decodeʹؔͯ͠ • ίʔϧͨ͠APIͷ໭Γ஋ͳͲʹ΋࢖͏͜ͱ͕Ͱ͖Δ
 • JSONʹؔͯ͠͸json_decodeͰ
 ͍͔ͭ͘Hack޲͚Φϓγϣϯ͕͋Γ
 • JSON_FB_COLLECTIONS => Map
 JSON_FB_HACK_ARRAYS => dict
 https://github.com/facebook/hhvm/blob/master/hphp/ hack/hhi/stdlib/builtins_json.hhi#L41
27. ΞϓϦέʔγϣϯ͕ฦ٫͢Δ΋ͷʹ ద༻ ݎ࿚ͳϨεϙϯεΛఏڙ͢Δ
28. ΞϓϦέʔγϣϯͰ࣮༻͢Δʹ͸ • HackͳΒϚΠΫϩαʔϏεʹ͓͚ΔAPI Gatewayͱ͔
 • ฦ٫͢Δ஋Λ୲อͯ͋͛͠ΔΑ͏ʹͨ͠΄͏͕ྑ͍
 • Ϟμϯͳ΋ͷͰ͋Ε͹ϛυϧ΢ΣΞΛ༻ҙͯ͠ɺ
 ࣗΒͷϨεϙϯεΛௐ΂Δ
29. ΦϨΦϨHackϑϨʔϜϫʔΫͰ ૊ΈࠐΜͰΈͨ https://github.com/ytake/nazg-skeleton
30. ࣮ફ • ΞΠελΠϧͰ͸HAL - Hypertext Application Language Λ࠾༻͍ͯ͠Δ
 • ߏ଄ΛshapeͰදݱ͢Δ • https://techblog.istyle.co.jp/2018/04/18/ hack%E3%81%A7%E4%BD%9C%E3%82%8B%E5%A0 %85%E5%AE%9F%E3%81%AAapi/

31. // goal { "id":1234, "name":"ytake", "title":"type-assert for api response", "_links":{ "self":{ “href":"/", "type":"application/json" } }, "_embedded":{ "enviroments":[ { "name":"HHVM/Hack", "_links":{ "self":{ "href":"https://docs.hhvm.com/" } } } ] } }
32. // shapeͰhal+jsonΛදݱ͢Δ const type embeddedLinks = shape( 'name' => string, '_links' => shape( 'self' => shape( 'href' => string ) ) ); const type hateoasStructure = shape( 'id' => int, 'name' => string, 'title' => string, '_links' => shape( 'self' => shape( 'href' => string, 'type' => string ) ), '_embedded' => shape( 'enviroments' => array<self::embeddedLinks> ) );
33. // ར༻ྫɹ͜͜Ͱ͸ImmMap new ImmMap([ 'id' => 1234, 'name' => 'ytake', 'title' => 'type-assert for api response', 'embedded' => [ [ 'name' => 'HHVM/Hack', 'url' => 'https://docs.hhvm.com/' ], ] ]);
34. ࣮ફ • ImmMapΛड͚औΓhal+jsonʹม׵
 • HalରԠϥΠϒϥϦ͸PHPͰ͍͔ͭ͋͘Δ
 Hack͸PHP͔Β཭Ε͍ͯͬͯΔͨΊɺ
 PHPϥΠϒϥϦ࢖͏ཧ༝΋ͳ͍ͷͰࣗ෼Ͱ࡞Δ(ͨ)
 • https://github.com/ytake/hhhal

35. protected Vector<HalResource> $vec = Vector{}; public function __construct( protected ImmMap<mixed, mixed> $resource ) {}
36. $map = $this->resource ->filterWithKey(($k, $v) ==> $k != 'embedded') ->toMap(); $hal = new HalResource($map); $hal->withLink(new Link( 'self', new Vector([ new LinkResource( '/', shape('type' => 'application/json')) ]), )); // hal+jsonରԠϥΠϒϥϦ࣮૷ྫ (Hack)
37. $embedded = $this->resource->get('embedded'); if(is_array($embedded)) { foreach($embedded as $row) { $embeddedResource = new HalResource(); foreach($row as $key => $value) { if($key === 'url') { $embeddedResource->withLink( new Link('self', new Vector([new LinkResource($value)])) ); continue; } $embeddedResource->addResource(strval($key), $value); } $this->vec->add($embeddedResource); } }
38. // γϦΞϥΠζ͢Δͱhal+jsonରԠͷjson͕ग़ྗ͞Ε·͢(Hack) $hal = $hal->withEmbedded('enviroments', $this->vec); $serialize = new Serializer(new JsonSerializer(), $hal); return $serialize->toArray();
39. ࣮ફ • ϛυϧ΢ΣΞͷ࠷ޙʹ࣮ߦ͢ΔΑ͏ʹ͢Δ
 • PSR-15४ڌͷϛυϧ΢ΣΞͰ͋Ε͹ͳΜͰ΋

40. public function process( ServerRequestInterface $request, RequestHandlerInterface $handler, ): ResponseInterface { $response = $handler->handle($request); // ϛυϧ΢ΣΞͷޙ൒Ͱಈ͘ $decode = json_decode($response->getBody()->getContents(), true); TypeAssert\matches_type_structure( type_structure(self::class, 'hateoasStructure'), $decode, ); return $response; }
41. <?hh // stirct use Psr\Log\LoggerInterface; use Ytake\HHContainer\Scope; use Ytake\HHContainer\ServiceModule; use Ytake\HHContainer\FactoryContainer; use App\Middleware\ResponseAssertMiddleware; final class MiddlewareServiceModule extends ServiceModule { public function provide(FactoryContainer $container): void { $container->set( ResponseAssertMiddleware::class, $container ==> new ResponseAssertMiddleware() ); // container΁ͷόΠϯυྫ } }
42. // route΋shapeͰෆ࣮֬͞Λͳ͘͢ʂ \Nazg\Http\HttpMethod::GET => ImmMap { '/' => shape( 'middleware' => ImmVector { App\Middleware\ResponseAssertMiddleware::class, App\Action\IndexAction::class, }, ) },
43. ·ͱΊ • strictҎ֎͸ͭΒ͍ • mixed΋ͭΒ͍ • ϚΠΫϩαʔϏεͰ౤ೖ͢ΔͳΒtype-assertΛ͓קΊ • inputͱoutput ৴༻͗ͯ͢͠͸͍͚ͳ͍ • null͕ʂܕ͕ʂͱݴΘΕͨΒHackͰఏڙͯ͠Έ·͠ΐ͏