exemplo-promises.php

exemplo-promises.php

<?php                                                                                                                                                                                                              
                                                                                                                                                                                               
require __DIR__ . '/autoload.php';                                                                                                                                                                       
                                                                                                                                                                                                                   
use Amp\Loop;                                                                                                                                                                                                      
use Amp\Artax\Request;                                                                                                                                                                                             
use Amp\Artax\DefaultClient;                                                                                                                                                                                       
                                                                                                                                                                                                                   
function requestJson($url) {                                                                                                                                                                                       
    return Amp\call(function () use ($url) { // A função call transforma um generator em uma promise pois o yield aceita somente promises                                                                          
        $client = new DefaultClient;                                                                                                                                                                               
        $request = (new Request($url))->withHeader('Accept', 'application/json');                                                                                                                                  
        $response = yield $client->request($request);                                                                                                                                                              
        $body = yield $response->getBody();                                                                                                                                                                        
        return json_decode($body, true);                                                                                                                                                                           
    });                                                                                                                                                                                                            
}                                                                                                                                                                                                                  
                                                                                                                                                                                                                   
function getDadJokes() {                                                                                                                                                                                           
    return Amp\call(function () {                                                                                                                                                                                  
        $json = yield requestJson('https://icanhazdadjoke.com/search?term=food');                                                                                                                                  
        return array_map(function ($result) { return $result['joke']; }, $json['results']);                                                                                                                        
    });                                                                                                                                                                                                            
}                                                                                                                                                                                                                  
                                                                                                                                                                                                                   
function getChuckNorrisJokes() {                                                                                                                                                                                   
    return Amp\call(function () {                                                                                                                                                                                  
        $json = yield requestJson('https://api.chucknorris.io/jokes/search?query=food');                                                                                                                           
        return array_map(function ($result) { return $result['value']; }, $json['result']);                                                                                                                        
    });                                                                                                                                                                                                            
}                                                                                                                                                                                                                  
                                                                                                                                                                                                                   
Loop::run(function () {                                                                                                                                                                                            
    $response = ['results' => []];                                                                                                                                                                                 
    try {                                                                                                                                                                                                          
        $jokeResults = yield [                                                                                                                                                                                     
            'dad' => getDadJokes(),                                                                                                                                                                                
            'chuckNorris' => getChuckNorrisJokes(),                                                                                                                                                                
        ];                                                                                                                                                                                                         
        foreach ($jokeResults as $apiName => $jokes) {                                                                                                                                                             
            foreach ($jokes as $joke) {                                                                                                                                                                            
                $response['results'][] = ['joke' => $joke, 'apiName' => $apiName];                                                                                                                                 
            }                                                                                                                                                                                                      
        }                                                                                                                                                                                                          
    } catch (Amp\Artax\HttpException $error) {                                                                                                                                                                     
        http_response_code(500);                                                                                                                                                                                   
        $response['error'] = $error->getMessage();                                                                                                                                                                 
    }                                                                                                                                                                                                              
    echo json_encode($response);                                                                                                                                                                                   
});