你也可以试试下面这段代码:

<?php
    define("GOOGLE_API_KEY", "AIzaSyCJiVkatisdQ44rEM353PFGbia29mBVscA");
    define("GOOGLE_GCM_URL", "https://android.googleapis.com/gcm/send");

    function send_gcm_notify($reg_id, $message) {
        $fields = array(
            'registration_ids'  => array( $reg_id ),
            'data'              => array( "message" => $message ),
        );

        $headers = array(
            'Authorization: key=' . GOOGLE_API_KEY,
            'Content-Type: application/json'
        );

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, GOOGLE_GCM_URL);
        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_encode($fields));

        $result = curl_exec($ch);
        if ($result === FALSE) {
            die('Problem occurred: ' . curl_error($ch));
        }

        curl_close($ch);
        echo $result;
    }

    $reg_id = "APA91bHuSGES.....nn5pWrrSz0dV63pg";
    $msg = "Google Cloud Messaging working well";

    send_gcm_notify($reg_id, $msg);

这段代码将通过PHP CURL向多个注册id发送一个GCM消息。

// Payload data you want to send to Android device(s)
// (it will be accessible via intent extras)    
$data = array('message' => 'Hello World!');

// The recipient registration tokens for this notification
// https://developer.android.com/google/gcm/    
$ids = array('abc', 'def');

// Send push notification via Google Cloud Messaging
sendPushNotification($data, $ids);

function sendPushNotification($data, $ids) {
    // Insert real GCM API key from the Google APIs Console
    // https://code.google.com/apis/console/        
    $apiKey = 'abc';

    // Set POST request body
    $post = array(
                    'registration_ids'  => $ids,
                    'data'              => $data,
                 );

    // Set CURL request headers 
    $headers = array( 
                        'Authorization: key=' . $apiKey,
                        'Content-Type: application/json'
                    );

    // Initialize curl handle       
    $ch = curl_init();

    // Set URL to GCM push endpoint     
    curl_setopt($ch, CURLOPT_URL, 'https://gcm-http.googleapis.com/gcm/send');

    // Set request method to POST       
    curl_setopt($ch, CURLOPT_POST, true);

    // Set custom request headers       
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

    // Get the response back as string instead of printing it       
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    // Set JSON post data
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($post));

    // Actually send the request    
    $result = curl_exec($ch);

    // Handle errors
    if (curl_errno($ch)) {
        echo 'GCM error: ' . curl_error($ch);
    }

    // Close curl handle
    curl_close($ch);

    // Debug GCM response       
    echo $result;
}

许多教程都过时了，甚至当前的代码都没有考虑设备注册id何时更新或设备取消注册。如果不检查这些项目，最终将导致无法接收消息的问题。http://forum.loungekatt.com/viewtopic.php?t=63#p181

这是我从CodeMonkeysRU分叉出来的一个库。

我分叉的原因是因为谷歌需要指数回退。我使用redis服务器将消息排队，并在设定的时间后重新发送。

我还将其更新为支持iOS。

https://github.com/stevetauber/php-gcm-queue

在搜索了很长一段时间后，我终于能够弄清楚我到底需要什么，连接到GCM使用PHP作为服务器端脚本语言，下面的教程将让我们清楚地了解如何设置我们需要开始使用GCM的一切

Android推送通知使用谷歌云消息(GCM)， PHP和MySQL

我知道这是一个晚的答案，但它可能对那些想要使用当前FCM格式(GCM已弃用)开发类似应用程序的人有用。 下面的PHP代码用于发送主题播客。所有在上述频道/topis注册的应用程序都会收到这个推送通知。

<?php

try{
$fcm_token = 'your fcm token';
$service_url = 'https://fcm.googleapis.com/fcm/send';
$channel = '/topics/'.$adminChannel;
echo $channel.'</br>';
      $curl_post_body = array('to' => $channel,
        'content_available' => true,
        'notification' => array('click_action' => 'action_open',
                            'body'=> $contentTitle,
                            'title'=>'Title '.$contentCurrentCat. ' Updates' ,
                            'message'=>'44'),
        'data'=> array('click_action' => 'action_open',
                            'body'=>'test',
                            'title'=>'test',
                            'message'=>$catTitleId));

        $headers = array(
        'Content-Type:application/json',
        'Authorization:key='.$fcm_token);

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $service_url);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($curl_post_body));

    $result = curl_exec($ch);
    if ($result === FALSE) {
        die('FCM Send Error: ' . curl_error($ch));
        echo 'failure';
    }else{

    echo 'success' .$result;
    }
    curl_close($ch);
    return $result;

}
catch(Exception $e){

    echo 'Message: ' .$e->getMessage();
}
?>