How do I transform large PHP object to JSON

Question

I am using CodeIgniter and I would like to store a representation of my emails in my database (to be picked up by a CRON job that sends out these emails). Because we realized there's too many emails being sent at once, causing some to not be sent at all. So we want to track in a database when one is sent correctly.

My database table contains the following columns:

CREATE TABLE `mail_queue`(
    `mail_id` INT(11) NOT NULL AUTO_INCREMENT, 
    `from` VARCHAR(255) NOT NULL,
    `to` VARCHAR(255) NOT NULL,
    `mail_object` JSON NOT NULL,
    `date_inserted` datetime DEFAULT CURRENT_TIMESTAMP,
    `priority` INT(11) NOT NULL,
    `mail_sent` INT(11) NOT NULL DEFAULT '0',
    INDEX `mail_queue_FI_1` (`priority`),
    INDEX `mail_queue_FI_2` (`mail_sent`),
    PRIMARY KEY (`mail_id`)
) ENGINE = InnoDB;

The following PHP code I have shows how to create an email:

//Initialize mail
        $this->load->library('email');

        $config['protocol'] = 'smtp';
        $config['smtp_host'] = 'smtp.office365.com';
        $config['smtp_user'] = GENERAL_MAIL;
        $config['smtp_pass'] = GENERAL_MAIL_PW;
        $config['smtp_port'] = '587';
        $config['charset']='utf-8';
        $config['newline']="\r\n";
        $config['crlf'] = "\r\n";
        $config['smtp_crypto'] = 'tls';
        $config['mailtype'] = 'html';
        $this->email->initialize($config);

        $this->email->from(GENERAL_MAIL, 'me');
        $this->email->to('dennis@me.com');
        $this->email->subject("test123cron");
        $message = $this->load->view('mail/membership/request',"123",TRUE);
        $this->email->message($message);

The object $this->email then contains a PHP object with quite a lot of parameters inside. Some are public and some are protected.

for example :

...
  public 'bcc_batch_mode' => boolean false
  public 'bcc_batch_size' => int 200
  protected '_safe_mode' => boolean false
  protected '_subject' => string '' (length=0)
  protected '_body' => string '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
    <meta name="format-detection" content="telephone=no" /> <!-- disable auto telephone linking in iOS -->
    <title> <title>Geregistr'... (length=49335)
  protected '_finalbody' => string '' (length=0)
...

By using json_encode it seems that only the public parameters are encoded in JSON while the protected are not.

I've read about implementing JsonSerialization, but according to the documentation "Specify data which should be serialized to JSON". Do I need to define each and every object parameter in there? I am not even sure if it's a fixed amount every time.

EDIT: I tried the suggestion as provided by the comment and my code is like this:

class Cron extends MY_Controller implements JsonSerializable
{
    public function __construct()
    {
        parent::__construct();
        // Force SSL
        $this->force_ssl();

        //Initialize mail
        $this->load->library('email');

        $config['protocol'] = 'smtp';
        $config['smtp_host'] = 'smtp.office365.com';
        $config['smtp_user'] = GENERAL_MAIL;
        $config['smtp_pass'] = GENERAL_MAIL_PW;
        $config['smtp_port'] = '587';
        $config['charset']='utf-8';
        $config['newline']="\r\n";
        $config['crlf'] = "\r\n";
        $config['smtp_crypto'] = 'tls';
        $config['mailtype'] = 'html';
        $this->email->initialize($config);
    }
    public function sendQueuingMails() {

        $this->email->from(GENERAL_MAIL, 'me');
        $this->email->to('dennis@me.com');
        $this->email->subject("test123cron");
        $message = $this->load->view('mail/membership/request',"123",TRUE);
        $this->email->message($message);

        var_dump($this->email);

        $jsonencode = json_encode($this->email);
        var_dump($jsonencode);

        $jsondecode = json_decode($jsonencode);
        var_dump($jsondecode);
    }

    public function jsonSerialize()
    {
        return get_object_vars($this);
    }
}

The output of the encoded JSON object is :

D:\wamp\www\codeigniter\application\controllers\cli\Cron.php:594:string '{"useragent":"CodeIgniter","mailpath":"\/usr\/sbin\/sendmail","protocol":"smtp","smtp_host":"smtp.office365.com","smtp_user":"dev@giveaday.be","smtp_pass":"266duZg6x4TP66Vn","smtp_port":"587","smtp_timeout":5,"smtp_keepalive":false,"smtp_crypto":"tls","wordwrap":true,"wrapchars":76,"mailtype":"html","charset":"utf-8","multipart":"mixed","alt_message":"","validate":false,"priority":3,"newline":"\r\n","crlf":"\r\n","dsn":false,"send_multipart":true,"bcc_batch_mode":false,"bcc_batch_size":200}' (length=495)

Which shows that it does not encode the protected attributes.

EDIT 2: based on the blog article linked below I changed the code of the jsonSerialize method to the following:

public function jsonSerialize()
        {
            $json = array();
            foreach($this as $key => $value) {
                $json[$key] = $value;
            }
            return $json;
        }

The result is the same. I noticed that the jsonSerialize method is just not being called. No matter what i put there, e.g. return "testtest"; it seems to keep on using the json_encode from somewhere else?

i think this is what you're looking for. https://stackoverflow.com/questions/7005860/php-json-encode-class-private-members — yasoh, Oct 05 '18 at 11:46
Thanks for the reply! This seems to not work for protected (modified my question to show new code) — Dennis, Oct 05 '18 at 12:03
Take a look at [this blog](https://jondavidjohn.com/show-non-public-members-with-json_encode/) — Michel, Oct 05 '18 at 12:14
@Michel Thanks for your reply! I tried the suggested solution at the bottom, did not work, the results were the same. Updated my question with the new code! — Dennis, Oct 05 '18 at 12:49

score 0 · Answer 1 · answered Oct 05 '18 at 12:19

0

Are you sure the JsonSerializeable didn't work?

class Cron implements \JsonSerializable
{
  protected $test1;
  private $test2;
  public function __construct()
  {
    $this->test1 = 'protected';
    $this->test2 = 'private';
  }


  public function jsonSerialize()
  {
    return get_object_vars($this);
  }
}

$cron = new Cron;

print_r(json_encode($cron->jsonSerialize()));

prints

{"test1":"protected","test2":"private"}

answered Oct 05 '18 at 12:19

yasoh

149
5

I realized that it isn't using the jsonSerialize method as I've defined it, why is this? – Dennis Oct 05 '18 at 13:05

How do I transform large PHP object to JSON

1 Answers1