如何使用PHP开发微信小程序的任务提醒功能？

<?php
$appid = "your_appid"; // 替换为小程序的 appid
$secret = "your_secret"; // 替换为小程序的密钥
$url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".$appid."&secret=".$secret;

$res = file_get_contents($url);
$res = json_decode($res);

$access_token = $res->access_token;

echo $access_token;
?>

<?php
$access_token = "your_access_token"; // 替换为上一步获取到的 access_token
$openid = "your_openid"; // 替换为需要发送模板消息的用户的 openid
$template_id = "your_template_id"; // 替换为你的模板消息 ID
$page = "pages/index/index"; // 替换为你的小程序页面路径
$form_id = "your_form_id"; // 替换为用户提交的 form_id

$data = array(
    'touser' => $openid,
    'template_id' => $template_id,
    'page' => $page,
    'form_id' => $form_id,
    'data' => [
        'keyword1' => ['value' => '任务提醒'], // 替换为模板消息中的字段内容
        'keyword2' => ['value' => '任务内容'],
        'keyword3' => ['value' => '任务时间']
    ],
);

$options = array(
    'http' => array(
        'method' => 'POST',
        'header' => 'Content-type:application/json',
        'content' => json_encode($data)
    )
);

$url = "https://api.weixin.qq.com/cgi-bin/message/wxopen/template/send?access_token=".$access_token;

$context = stream_context_create($options);
$res = file_get_contents($url, false, $context);

echo $res;
?>