Tutorial fcm php

$serverKey = 'Chave da sua api Firebase';
                            $msg_notificacao = "Mensagem da notificacao";

                            $pushUrl    = "https://fcm.googleapis.com/fcm/send";
                            $key        = $serverKey;
                            $headers    = [];

                            $headers[] = 'Content-Type: application/json';
                            $headers[] = 'Authorization:key=' . $key;
                            $data  = array(
                                'registration_ids' => //'Aqui vai um array com os tokens fcm dos usuarios que irao receber essa notificacao',
                                "notification" => array(
                                        "title"         =>  "Titulo da sua notificacao",
                                        "body"          =>  $msg_notificacao,
                                        "click_action"  =>"FCM_PLUGIN_ACTIVITY",
                                        "icon"          => "fcm_push_icon",
                                        "priority" => "high",
                                        "show_in_foreground" => true,
                                        "targetScreen" => 'detail'
                                ),
                                "data" => array(
                                        "notification" => array(
                                            "title" =>  "Titulo da sua notificacao",
                                            "body" =>  $msg_notificacao,
                                            "click_action" =>"FCM_PLUGIN_ACTIVITY",
                                            "icon" => "fcm_push_icon",
                                            "priority" => "high",
                                            "show_in_foreground" => true,
                                            "targetScreen" => 'detail',
                                            //dados de seu backend que queira mandar para o ionic esses 3 abaixos
                                            "dia" => "Convite para um jogo",
                                            "email_cancelou" => 'blablabla',
                                            "aviso" => "sim",

                                        )
                                ),
                                "priority" => 10,
                            );
                            $json_data = json_encode($data);

                            $ch = curl_init();
                            curl_setopt($ch, CURLOPT_URL, 'https://fcm.googleapis.com/fcm/send');
                            curl_setopt($ch, CURLOPT_POST, true);
                            curl_setopt($ch,CURLOPT_HTTPHEADER, $headers);
                            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
                            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
                            curl_setopt($ch, CURLOPT_POSTFIELDS, $json_data);

                            $res = curl_exec($ch);
                            curl_close($ch);