[API] Add check_auth function with json output

application/controllers/Api.php

@@ -127,6 +127,29 @@ class API extends CI_Controller {
 		}
 	}
 
+	function check_auth($key) {
+		$this->load->model('api_model');
+			header("Content-type: text/xml");
+		if($this->api_model->access($key) == "No Key Found" || $this->api_model->access($key) == "Key Disabled") {
+			// set the content type as json
+			header("Content-type: application/json");
+
+			// set the http response code to 401
+			http_response_code(401);
+
+			// return the json with the status as failed
+			echo json_encode(['status' => 'failed', 'reason' => "missing or invalid api key"]);
+		} else {
+			// set the content type as json
+			header("Content-type: application/json");
+
+			// set the http response code to 200
+			http_response_code(200);
+			// return the json
+			echo json_encode(['status' => 'valid', 'rights' => $this->api_model->access($key)]);
+		}
+	}
+
 	function station_info($key) {
 		$this->load->model('api_model');
 		$this->load->model('stations');