Sending push notification using OneSignal API where title and content passed from iOS app as json body

methods.swift

func panic() {
    let url = URL(string: "https://mywebsite.com/send.php")!
    let parameters = ["title": "Some title", "content": "Some content"]
    let body = try! JSONSerialization.data(withJSONObject: parameters, options: [])
    
    let request = URLRequest(url: url)
    request.httpMethod = "POST"
    request.setValue("application/json", forHTTPHeaderField: "Content-Type")
    request.httpBody = body
    
    
    let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
        if let error = error {
            print("error:", error)
            return
        }

        do {
            guard let data = data else { return }
            guard let json = try JSONSerialization.jsonObject(with: data, options: []) as? [String: AnyObject] else { return }
            print("json:", json)
        } catch {
            print("error:", error)
        }
    }

    task.resume()
}

send.php

<?php
function sendMessage($input) {    
    $content = ["en" => $input['content']];
    $title = ["en" => $input['title']];
    $body = json_encode([
      'app_id' => "MYAPPID",
      'included_segments' => ['All']
      'data' => ["foo" => "bar"],
      'contents' => $content,
      'headings' => $title
    ]);
    
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://onesignal.com/api/v1/notifications");
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
      'Content-Type: application/json; charset=utf-8',
      'Authorization: Basic MYAPIKEY'
    ]);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
    
    $response = curl_exec($ch);
    curl_close($ch);
    
    return $response;
}

$input = json_decode(file_get_contents('php://input'), true);

$response = sendMessage($input);
header('Content-Type: application/json');
print $response;