add MAL Heartbeat info to / root response

.env.dist

@@ -35,6 +35,9 @@ SOURCE_BAD_HEALTH_RECHECK=10
 SOURCE_BAD_HEALTH_RANGE=30
 # Max Fail stores
 SOURCE_BAD_HEALTH_MAX_STORE=50
+# Disable failover if the score reaches the following (0.0-1.0 values ONLY)
+# e.g 0.9 means 90% successful requests to MyAnimeList
+SOURCE_GOOD_HEALTH_SCORE=0.9
 # Max time request is allowed to take
 # https://curl.haxx.se/libcurl/c/CURLOPT_TIMEOUT.html
 SOURCE_TIMEOUT=5

app/Http/Middleware/SourceHeartbeatMonitor.php

@@ -16,7 +16,7 @@ class SourceHeartbeatMonitor
      */
     public function handle($request, Closure $next)
     {
-        event(new SourceHeartbeatEvent(SourceHeartbeatEvent::GOOD_HEALTH, 200));
+        event(new SourceHeartbeatEvent(SourceHeartbeatEvent::GOOD_HEALTH, 500));
 
         return $next($request);
     }

app/Listeners/SourceHeartbeatListener.php

@@ -86,7 +86,7 @@ class SourceHeartbeatListener
     {
         $score = $this->getSuccessfulRequestsScore();
 
-        if ($score >= 0.9) {
+        if ($score >= env('SOURCE_GOOD_HEALTH_SCORE', 0.9)) {
             $this->disableFailover();
             $this->logger->debug('Failover disabled; Score: '.$score);
             $this->logger->debug('Failover DISABLED');

app/Providers/SourceHeartbeatProvider.php

@@ -2,6 +2,7 @@
 
 namespace App\Providers;
 
+use App\Events\SourceHeartbeatEvent;
 use Illuminate\Support\Facades\Storage;
 use Laravel\Lumen\Providers\EventServiceProvider as ServiceProvider;
 
@@ -25,4 +26,64 @@ class SourceHeartbeatProvider extends ServiceProvider
     {
         return Storage::exists('source_failover.lock');
     }
+
+    public static function getLastDowntime() : int
+    {
+        try {
+            return Storage::lastModified('source_failover.lock');
+        } catch (\Exception $e) {
+            return 0;
+        }
+    }
+
+    public static function getHeartbeatScore() : float
+    {
+        try {
+            $failsJson = Storage::get('failovers.json');
+            $fails = json_decode($failsJson, true);
+        } catch (\Exception $e) {
+            $fails = [];
+        }
+
+        // remove any fails greater than SOURCE_BAD_HEALTH_RANGE
+        foreach ($fails as $fail) {
+
+            if ($fail[0] >= (time()-env('SOURCE_BAD_HEALTH_RANGE'))) {
+                unset($fail);
+            }
+        }
+
+        // slice
+        if (count($fails) > env('SOURCE_BAD_HEALTH_MAX_STORE')) {
+            $fails = array_slice($fails, 0 - env('SOURCE_BAD_HEALTH_MAX_STORE'));
+        }
+
+        $score = 0;
+        $totalFails = count($fails) - 1;
+
+        foreach ($fails as $fail) {
+            if ((int) $fail[2] === SourceHeartbeatEvent::GOOD_HEALTH) {
+                $score++;
+            }
+        }
+
+        $scored = $score / max($totalFails, 1);
+
+        return $scored;
+    }
+
+    public static function getHeartbeatStatus() : string
+    {
+        $score = self::getHeartbeatScore();
+
+        if ($score > 0.5 && $score < env('SOURCE_GOOD_HEALTH_SCORE')) {
+            return "LEARNING";
+        }
+
+        if ($score <= 0.5) {
+            return "UNHEALTHY";
+        }
+
+        return "HEALTHY";
+    }
 }

routes/web.v4.php

@@ -12,7 +12,13 @@ $router->get('/', function () use ($router) {
         'github_url' => 'https://github.com/jikan-me/jikan-rest',
         'parser_github_url' => 'https://github.com/jikan-me/jikan',
         'production_api_url' => 'https://api.jikan.moe/v4/',
-        'status_url' => 'https://status.jikan.moe'
+        'status_url' => 'https://status.jikan.moe',
+        'myanimelist_heartbeat' => [
+            'status' => \App\Providers\SourceHeartbeatProvider::getHeartbeatStatus(),
+            'score' => \App\Providers\SourceHeartbeatProvider::getHeartbeatScore(),
+            'down' => \App\Providers\SourceHeartbeatProvider::isFailoverEnabled(),
+            'last_downtime' => \App\Providers\SourceHeartbeatProvider::getLastDowntime()
+        ]
     ]);
 });