use route string to avoid hitting high cardinality path.

doc/zh-cn/metric.md

@@ -218,7 +218,7 @@ return [
     ],
 ];
 ```
-> 本中间件中统计维度包含 `request_status`、`request_path`、`request_method`, 如果您的 `request_path` 包含无限种可能(比如`/users/{id}`)，则建议重写本中间件，去掉 `request_path` 维度，否则过高的基数会导致内存溢出。
+> 本中间件中统计维度包含 `request_status`、`request_path`、`request_method`。如果您的 `request_path` 过多，则建议重写本中间件，去掉 `request_path` 维度，否则过高的基数会导致内存溢出。
 
 ### 自定义使用
 

src/metric/composer.json

@@ -34,7 +34,8 @@
         "hyperf/di": "Required to use annotations.",
         "hyperf/event": "Required to use listeners for default metrics.",
         "hyperf/process": "Required to use standalone process, or you have to roll your own",
-        "hyperf/retry": "Required to use back-off retry implementation."
+        "hyperf/retry": "Required to use back-off retry implementation.",
+        "hyperf/http-server": "Required to capture routes in middleware."
     },
     "autoload": {
         "psr-4": {

src/metric/src/Listener/OnWorkerStart.php

@@ -24,7 +24,6 @@ use Psr\Container\ContainerInterface;
 use Psr\EventDispatcher\EventDispatcherInterface;
 use Swoole\Server;
 use Swoole\Timer;
-use Throwable;
 use function gc_status;
 use function getrusage;
 use function memory_get_peak_usage;
@@ -159,7 +158,7 @@ class OnWorkerStart implements ListenerInterface
                     $this->factory->handle();
                 });
             } else {
-                retry(PHP_INT_MAX, function(){
+                retry(PHP_INT_MAX, function () {
                     $this->factory->handle();
                 }, 100);
             }

src/metric/src/Listener/PoolWatcher.php

@@ -41,8 +41,6 @@ abstract class PoolWatcher
         ];
     }
 
-    abstract protected function getPrefix();
-
     /**
      * Periodically scan metrics.
      */
@@ -79,4 +77,6 @@ abstract class PoolWatcher
             $connectionsInUseGauge->set((float) $pool->getCurrentConnections());
         });
     }
+
+    abstract protected function getPrefix();
 }

src/metric/src/Middleware/MetricMiddleware.php

@@ -12,7 +12,7 @@ declare(strict_types=1);
 
 namespace Hyperf\Metric\Middleware;
 
-use Hyperf\Metric\Contract\MetricFactoryInterface;
+use Hyperf\HttpServer\Router\Dispatched;
 use Hyperf\Metric\Timer;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
@@ -29,9 +29,15 @@ class MetricMiddleware implements MiddlewareInterface
      */
     public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
     {
+        $dispatched = $request->getAttribute(Dispatched::class);
+        if (! $dispatched) {
+            $route = $request->getUri()->getPath();
+        } else {
+            $route = $dispatched->handler->route;
+        }
         $labels = [
             'request_status' => '500', //default to 500 in case uncaught exception occur
-            'request_path' => $request->getUri()->getPath(),
+            'request_path' => $route,
             'request_method' => $request->getMethod(),
         ];
         $timer = new Timer('http_requests', $labels);