pp.php

<?php

class Endpoint {
    function __construct(public string $url, ?callable $dfunc=null, array $opts = []) {
        $this->context = stream_context_create($opts);
        $this->dfunc = $dfunc ? $dfunc : fn($x)=>$x;
    }
}

class Api {
    static public ?weakMap $cache = null;
    static public function fetch(Endpoint $ep): string|object {
        if(!self::$cache) self::$cache = new weakMap;
        return self::$cache[$ep] ??= $ep->dfunc->call($ep, file_get_contents($ep->url, context:$ep->context));
    }
}

$xkcd = new Endpoint("http://xkcd.com/info.0.json", fn($x)=>json_decode($x, associative:false));
$joke = new Endpoint("https://icanhazdadjoke.com/", opts:['http'=>['header'=>"Accept: text/plain"]]);

echo '<img src="'.Api::fetch($xkcd)->img.'" alt="'.Api::fetch($xkcd)->alt.'">'."\n";
echo Api::fetch($joke) . "\n";
echo Api::$cache->count() . "\n"; // 3
unset($xkcd);
echo Api::$cache->count() . "\n"; // 2
echo Api::fetch($joke) . "\n";    // Same bad joke
$joke = new Endpoint("https://icanhazdadjoke.com/", opts:['http'=>['header'=>"Accept: text/plain\r\n"]]);
echo Api::fetch($joke) . "\n";    // New bad joke
echo Api::$cache->count() . "\n"; // 3?
gc_collect_cycles();              // Force gc
echo Api::$cache->count() . "\n"; // 2