Updated service to support multiple types

Added support for callable, EndpointHandler, and class name to the input for the handler function to allow for greater flexibility

README.md

@@ -304,39 +304,51 @@ $stream->put('mailer.bye', $payload);
 The services feature provides a simple way to create microservices that leverage NATS.
 
 In the example below, you will see an example of creating an index function for the posts microservice. The request can 
-be accessed under "v1.posts.index". You can add multiple endpoints to support your service. 
+be accessed under "v1.posts" and then individual post by "v1.posts.{post_id}". 
 ```php
 // Define a service
-$service = $client->service('PostsService', 'This service is responsible for handling all things post related.', '1.0');
+$service = $client->service(
+    'PostsService', 
+    'This service is responsible for handling all things post related.', 
+    '1.0'
+);
 
 // Create the version group
 $version = $service->addGroup('v1');
 
-// Create the service group
-$posts = $version->addGroup('posts')
-
-// Create the endpoint handler
-class IndexPosts implements \Basis\Nats\Service\ServiceHandler {
+// Create the index posts endpoint handler
+class IndexPosts implements \Basis\Nats\Service\EndpointHandler {
 
     public function handle(\Basis\Nats\Message\Payload $payload): array 
     {
         // Your application logic
         return [
-            'hello' => 'world'
+            'posts' => []
         ];
     }
 }
 
-// Create an endpoint
+// Create the index endpoint 
+$version->addEndpoint("posts", IndexPosts::class);
+
+// Create the service group
+$posts = $version->addGroup('posts');
+
+// View post endpoint
 $posts->addEndpoint(
-    'index',
-    new IndexPosts()
+    '*',
+    function (\Basis\Nats\Message\Payload $payload) {
+        $postId = explode('.', $payload->subject);
+        $postId = $postId[count($postId)-1];
+
+        return [
+            'post' => []        
+        ];    
+    }
 );
 
 // Run the service
-while (true) {
-    $client->process();
-}
+$service->run();
 ```
 
 

src/Service/Service.php

@@ -120,7 +120,7 @@ public function addGroup(string $name): ServiceGroup
 
     public function addEndpoint(
         string $name,
-        EndpointHandler $endpointHandler,
+        string|EndpointHandler|callable $endpointHandler,
         array $options = []
     ): void {
         $subject = $name;
@@ -203,4 +203,16 @@ private function controlSubject(string $verb, string $name, string $id): string
 
         return "\$SRV.$verb.$name.$id";
     }
+
+    public function run() : void
+    {
+        print_r("$this->name is ready to accept connections\n");
+        while(true) {
+            try {
+                $this->client->process();
+            } catch (\Exception $e) {
+                print_r("$this->name encountered an error:\n" . $e->getMessage() . "\n");
+            }
+        }
+    }
 }

src/Service/ServiceEndpoint.php

@@ -19,11 +19,11 @@ class ServiceEndpoint
     private Client|Queue $subscription;
 
     public function __construct(
-        private readonly Service         $service,
-        private readonly string          $name,
-        private readonly string          $subject,
-        private readonly EndpointHandler $endpointHandler,
-        private readonly string          $queue_group = 'q'
+        private readonly Service $service,
+        private readonly string  $name,
+        private readonly string  $subject,
+        private                  $endpointHandler,
+        private readonly string  $queue_group = 'q'
     )
     {
         $this->subscription = $this->service->client->subscribeQueue(
@@ -36,8 +36,30 @@ function (Payload $message) {
                 // Update the endpoint metrics
                 $this->num_requests += 1;
 
-                // Run the handler
-                $response = $this->endpointHandler->handle($message);
+                // Setup the response
+                $response = "";
+
+                switch ($this->endpointHandler) {
+                    case is_string($this->endpointHandler):
+                        // Instantiate the endpointHandler
+                        $handler = new $this->endpointHandler();
+
+                        // Check to make sure that the class implements ServiceEndpoint
+                        if (!($handler instanceof EndpointHandler)) {
+                            throw new \LogicException("Class must implement EndpointHandler");
+                        }
+
+                        $response = $handler->handle($message);
+                        break;
+                    case is_callable($this->endpointHandler):
+                        $func = $this->endpointHandler;
+
+                        $response = $func($message);
+                        break;
+                    case $this->endpointHandler instanceof EndpointHandler:
+                        $response = $this->endpointHandler->handle($message);
+                        break;
+                }
 
                 // Add to the total processing time
                 $this->processing_time += microtime(true) - $start;

src/Service/ServiceGroup.php

@@ -20,7 +20,7 @@ public function addGroup(string $name): ServiceGroup
 
     public function addEndpoint(
         string   $name,
-        EndpointHandler $serviceHandler,
+        string|EndpointHandler|callable $serviceHandler,
         array    $options = []
     ): void
     {