http://roma2017.drupalday.it

http://www.bmeme.com

http://www.bmeme.com

Adriano Cori

• drupal.org: aronne • github.com: Fatal-Error • twitter: @coriadriano • email: adriano.cori@bmeme.com

return shuffle([ "programmazione", "famiglia", "videogames", "calcio", ]);

HTTPDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:

Adriano Cori, @bmeme DrupalDay Roma

3 Marzo 2017

CLIENT MANAGER

HTTP CLIENT MANAGER

“L'HyperText Transfer Protocol (HTTP) è un protocollo a livello applicativo usato come principale sistema per la trasmissione d'informazioni sul web ovvero in un'architettura tipica client-

server.” - https://it.wikipedia.org/wiki/Hypertext_Transfer_Protocol

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:

HTTP REQUESTDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

• POST • GET • PUT, PATCH • DELETE • OPTIONS • HEAD • TRACE • CONNECT

> Request Method

• CREATE • RETRIEVE • UPDATE • DELETE

> Request URI

Lo uniform resource identifier indica l'oggetto della richiesta

> Request Header

• Host • User-Agent • Accept

HTTP RESPONSEDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

• 200 • 301 • 302 • 307 • 400 • 404 • 500 • 505

> Response Status

Ok Moved Permanently Found Temporary Redirect Bad Request Not Found Internal Server Error HTTP Version Unsupported

> Response body

Contiene il contenuto della risposta

> Response Header

• Date • Content-Type • Cache-Control

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

“REpresentational State Transfer (REST) è un tipo di architettura software per i sistemi di ipertesto distribuiti come il World Wide

Web.” - https://it.wikipedia.org/wiki/Representational_State_Transfer

“REST defines a set of architectural principles by which you can design Web services that focus on a system's resources, including how resource states are addressed and transferred over HTTP by a

wide range of clients written in different languages.” - https://www.ibm.com/developerworks/webservices/library/ws-restful

/** * * * * * * * * * * * * * * * * * */

@see \Drupal\sparkfabrik\PaoloPustorino::restInPieces()

REST SERVICEDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

> HTTP ResponseHTTP/1.1 200 OKContent-Type: application/json; charset=UTF-8 [ {

"id": 1, "title": "Ma che bella notizia", "body": "Lorem ipsum non passa mai di moda", "date": "2017-03-03 10:15:32”

}, {

"id": 2, "title": "Inizia il talk di @aronne", "body": "Lorem ipsum come se piovesse", "date": "2017-03-03 10:02:54”

} ]

GET /api/news?date=2017-03-03 HTTP/1.1 Host: example.com User-Agent: curl/7.43.0 Accept: application/json

> HTTP Request

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

“An HTTP client uses HTTP to connect to a web server over the Internet to transfer documents or other data. The most well known

types of HTTP Clients include web browsers.” - https://en.wikipedia.org/wiki/Category:Hypertext_Transfer_Protocol_clients

Cosa ci mette a disposizione Drupal 8?

\Drupal::httpClient()public static function httpClient() { return static::getContainer()->get('http_client'); }

http_client: class: GuzzleHttp\Client factory: http_client_factory:fromOptions

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

$news = \Drupal::httpClient()->request( 'GET', 'http://api.example.com/news', ['date' => '2017-03-03'] );

“Ahah..ma come Guzzle se fa dico io”

Alternative?

ALTERNATIVEDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

Creare una classe che faccia da wrapper al \Drupal::httpClient()

• Memorizzare l’host tanto per cominciare • Creare dei metodi ad hoc per ogni Request • Validazione dei parametri • Design pattern a piacere :) • Riusabilità del codice • …

e poi un bel giorno….

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

REFACTORINGDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

Creare una classe astratta che faccia da bla bla bla…

• Programmazione orientata agli insulti • Il nuovo codice va ritestato • la tua ragazza ti lascia • il corvo si sbagliava riguardo alla pioggia • belle sbuffate • io manco ce volevo veni’ • e mettemocela n’altra if… • AggileGiggi me spiccia casa

ma poi alla fine….

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

REFACTORINGDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

Come si potrebbe migliorare ancora il nostro codice?

• Rendendolo (se non lo si era già fatto) il più astratto possibile • Rimuovendo dal codice info relative agli endpoint, risorse e

parametri, spostandole invece su dei file di configurazione • cancellandolo…

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

Http Client Manager introduces a new Guzzle based plugin which allows you to manage HTTP clients using Guzzle Service Descriptions via JSON files, in a simple and efficient way:

"Service descriptions define web service APIs by documenting each operation, the operation's parameters, validation options for each parameter, an operation's response, how the response is parsed, and any errors that can be raised for an operation. Writing a service description for a web service allows you to more quickly consume a web service than writing concrete commands for each web service operation.”

You will no longer need to write down Http services calls each times specifying endpoints and parameters in a totally decentralized way.

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER> Http Services Api definition via *.http_services_api.yml file example_services: title: "Example Services - posts API" api_path: "src/api/example_services.json" base_url: "http://api.example.com"

auth_services: title: "Another Example Services - auth API" api_path: "src/api/auth_services.json" base_url: “http://auth.services.com"

> Overridable Services Api definition via settings.php file $settings['http_services_api']['example_services'] = [ 'title' => 'Example Services - posts API (Development)', 'base_url' => 'http://api.example.dev', ];

> Ad Hoc client definition via *.services.yml file services: example_api.http_client: parent: http_client_manager.client_base arguments: ['example_services']

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

> src/api/example_services.json { "name": "ExampleServicesApi", "apiVersion": "2016-07-29", "description": "Example Services API descriptions.", "includes" : [ "resources/posts.json" ] }

> src/api/resources/posts.json { "operations": { "FindPosts": { "httpMethod": "GET", "uri": "posts/{postId}", "summary": "Find posts", "parameters": { "postId": { "location": "uri", "description": "Filter posts by id", "required": false, "type": "string" } } }, "models": {} }

HTTP SERVICE DESCRIPTIONS

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER> Multiple ways to instantiate http clients

// Client instantiation via http_client_manager service factory method. $client = \Drupal::service('http_client_manager.factory')->get('example_services');

// Client instantiation via service. $client = \Drupal::service(‘example_api.http_client');

> Multiple ways to execute http requests

// Call method usage. $latestPosts = $client->call('FindPosts', ['limit' => '10', 'sort' => 'desc']);

// Magic method usage. $latestPosts = $client->findPosts(['limit' => '10', 'sort' => 'desc']);

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGERYou can also create and store (bookmark) predefined requests via web UI as Configuration Entities (exportable via Configuration Manager), and execute them from your code in this way:

// Http Config Request usage via Config Entity static method. $latestPosts = HttpConfigRequest::load('find_posts')->execute();

// Http Config Request usage via entity type manager. $latestPosts = $this->entityTypeManager()

->getStorage('http_config_request') ->load('find_posts') ->execute();

DRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER/** * Class HttpEventSubscriber. */ class HttpEventSubscriber implements EventSubscriberInterface {

/** * {@inheritdoc} */ static function getSubscribedEvents() { return [ 'request.before_send' => array('onRequestBeforeSend', -1000) ]; }

/** * Request before-send event handler * * @param Event $event * Event received */ public function onRequestBeforeSend(Event $event) {

// your code goes here… } }

CONCLUSIONIDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:HTTP CLIENT MANAGER

HTTP Client Manager in cosa ci aiuta?

• Ad evitare la dispersione del codice centralizzandone l’utilizzo • Ad evitare di scrivere altro codice in favore di un riutilizzo delle

descrizioni dei servizi • A risolvere un problema comune proponendosi quindi come un

nuovo standard per la gestione delle sorgenti e per lapresentazione di dati nelle istanze Drupal che consumano servizi

HTTP CLIENT MANAGERDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:

LIVE DEMOQUESTIONS& ANSWERS

HTTP CLIENT MANAGERDRUPAL COME FRONT-END CHE CONSUMA SERVIZI REST:

LIVE DEMOQUESTIONS& ANSWERS