No value of property after setting visibility

Thoulah · June 5, 2020, 4:06pm

Im pretty sure the issue below is a case of me not fully understanding PHP 7.4 Typed Properties (aka PEBKAC), but after retrieving values from DB over ActiveRecord I end up with the following:

object(mister42\models\music\Collection)#90 (10) {
  ["artist":"mister42\models\music\Collection":private]=>
  uninitialized(string)
  ["created":"mister42\models\music\Collection":private]=>
  uninitialized(string)
  ["id":"mister42\models\music\Collection":private]=>
  uninitialized(int)
  ["image":"mister42\models\music\Collection":private]=>
  uninitialized(?string)
  ["image_color":"mister42\models\music\Collection":private]=>
  uninitialized(?string)
  ["image_override":"mister42\models\music\Collection":private]=>
  uninitialized(?string)
  ["status":"mister42\models\music\Collection":private]=>
  uninitialized(string)
  ["title":"mister42\models\music\Collection":private]=>
  uninitialized(string)
  ["user_id":"mister42\models\music\Collection":private]=>
  uninitialized(int)
  ["year":"mister42\models\music\Collection":private]=>
  uninitialized(int)
  ["_attributes":"yii\db\BaseActiveRecord":private]=>
  array(11) {
    ["id"]=>
    int(281014)
    ["user_id"]=>
    int(1)
    ["artist"]=>
    string(12) "Angel Theory"
    ["year"]=>
    string(4) "2004"
    ["title"]=>
    string(15) "Fatal Condition"
    ["image"]=>
    string(7725) "<<binary string deleted>>"
    NULL
    ["image_color"]=>
    string(7) "#DFE4E8"
    ["status"]=>
    string(10) "collection"
    ["created"]=>
    string(19) "2019-10-10 20:52:32"
    ["updated"]=>
    string(19) "2020-06-04 22:56:10"
  }
  ["_oldAttributes":"yii\db\BaseActiveRecord":private]=>
  array(11) {
    ["id"]=>
    int(281014)
    ["user_id"]=>
    int(1)
    ["artist"]=>
    string(12) "Angel Theory"
    ["year"]=>
    string(4) "2004"
    ["title"]=>
    string(15) "Fatal Condition"
    ["image"]=>
    string(7725) "<<binary string deleted>>"
    ["image_override"]=>
    NULL
    ["image_color"]=>
    string(7) "#DFE4E8"
    ["status"]=>
    string(10) "collection"
    ["created"]=>
    string(19) "2019-10-10 20:52:32"
    ["updated"]=>
    string(19) "2020-06-04 22:56:10"
  }
  ["_related":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_relationsDependencies":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_errors":"yii\base\Model":private]=>
  NULL
  ["_validators":"yii\base\Model":private]=>
  NULL
  ["_scenario":"yii\base\Model":private]=>
  string(7) "default"
  ["_events":"yii\base\Component":private]=>
  array(0) {
  }
  ["_eventWildcards":"yii\base\Component":private]=>
  array(0) {
  }
  ["_behaviors":"yii\base\Component":private]=>
  array(0) {
  }
}

How can I have uninitialized in the Object and values in _attributes at the same time? How do I get rid of the uninitialized after self::findOne?

samdark · June 6, 2020, 7:47am

Try updating Yii version.

Thoulah · June 6, 2020, 9:15am

This is on version 2.0.35.

<?php

namespace mister42\models\music;

use Yii;

class Test extends \yii\db\ActiveRecord
{
    private string $artist;
    private string $created;
    private int $id;
    private ?string $image;
    private ?string $image_color;
    private ?string $image_override;
    private string $status;
    private string $title;
    private string $updated;
    private int $user_id;
    private int $year;

    public static function getEntryLastModified(int $id): int
    {
        $data = self::find()->where(['id' => $id])->limit(1)->one();
        var_dump($data);exit; #shows output above
        return isset($data->updated) ? Yii::$app->formatter->asTimestamp($data->updated) : time();
    }

    public static function tableName(): string
    {
        return '{{%discogs_collection}}';
    }
}

Thoulah · June 6, 2020, 10:14am

Same result on 2.0.36-dev

mbunyan · June 6, 2020, 2:27pm

My understanding is that it is thus important to make sure it is given a value before accessing a property. The best ways to enforce this are making sure the property is set in the constructor or giving them default values.

A ‘__construct’ method may be overkill, but you could assign default values which might look like this:

private string $created = "";
private int $id = 0;
private ?string $image = null;

Thoulah · June 6, 2020, 2:44pm

I don’t think I should have to do that, as that would be a job of the framework. However, Yii still won’t set any values:

private string $title = '';

public static function getEntryLastModified(int $id): int
{
    $data = self::find()->where(['id' => $id])->limit(1)->one();
    var_dump($data->title);
    var_dump($data->attributes['title']);
    exit;
}

string(0) ""
string(15) "Fatal Condition"

No error, but an empty string from the assignment.

samdark · June 6, 2020, 7:35pm

Alright. Now I remember the issue. Here it is:

Thoulah · June 6, 2020, 7:44pm

I don’t think that issue applied here:

It is talking about user entered data from a form. The error there is at the moment of validating data.
I am trying to retrieve data from database (no need to re-validate), but am now facing empty object values.

batyrmastyr · June 6, 2020, 8:57pm

I may be wrong, but Yii2 assigns db/ActiveRecord values to _attributes If they are listed in ::attributes(), and to real properties otherwise. So you have to override::attributes() to return empty array… but thus you’ll break getDirtyAttributes and everything that relies on in: smart update and updateAttributes, because they rely on _attributes and _oldAttributes.

So, I see no way to use typed properties in Yii2 the way you want.

Thoulah · June 7, 2020, 9:58am

I have been able to bring it down to a much more basic issue. Yii2 does not set the value to any property with a set visibility.

public $value; causes $this->value to be NULL

object(mister42\models\test\Test)#113 (11) {
  ["value"]=>
  NULL
  ["_attributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_oldAttributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_related":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_relationsDependencies":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_errors":"yii\base\Model":private]=>
  NULL
  ["_validators":"yii\base\Model":private]=>
  NULL
  ["_scenario":"yii\base\Model":private]=>
  string(7) "default"
  ["_events":"yii\base\Component":private]=>
  array(0) {
  }
  ["_eventWildcards":"yii\base\Component":private]=>
  array(0) {
  }
  ["_behaviors":"yii\base\Component":private]=>
  array(0) {
  }
}

var_dump($data->value); //NULL

public $value = 'test'; causes $this->value to be string(4) "test"instead of the assign attribute value

object(mister42\models\test\Test)#113 (11) {
  ["value"]=>
  string(4) "test"
  ["_attributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_oldAttributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_related":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_relationsDependencies":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_errors":"yii\base\Model":private]=>
  NULL
  ["_validators":"yii\base\Model":private]=>
  NULL
  ["_scenario":"yii\base\Model":private]=>
  string(7) "default"
  ["_events":"yii\base\Component":private]=>
  array(0) {
  }
  ["_eventWildcards":"yii\base\Component":private]=>
  array(0) {
  }
  ["_behaviors":"yii\base\Component":private]=>
  array(0) {
  }
}

var_dump($data->value); //string(4) "test"

removing the visibility works as expected

object(mister42\models\test\Test)#113 (10) {
  ["_attributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_oldAttributes":"yii\db\BaseActiveRecord":private]=>
  array(2) {
    ["id"]=>
    int(1)
    ["value"]=>
    string(9) "Yii2 test"
  }
  ["_related":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_relationsDependencies":"yii\db\BaseActiveRecord":private]=>
  array(0) {
  }
  ["_errors":"yii\base\Model":private]=>
  NULL
  ["_validators":"yii\base\Model":private]=>
  NULL
  ["_scenario":"yii\base\Model":private]=>
  string(7) "default"
  ["_events":"yii\base\Component":private]=>
  array(0) {
  }
  ["_eventWildcards":"yii\base\Component":private]=>
  array(0) {
  }
  ["_behaviors":"yii\base\Component":private]=>
  array(0) {
  }
}

var_dump($data->value); //string(9) "Yii2 test"

lubosdz · June 10, 2020, 11:55am

If your validator is e.g. string, then add filter for all stringual attributes:

[
   [['name'], 'filter', filter => 'trim'], // <- typecast NULL/numeric to string
   [['name'], 'string'],
]

Same for numeric - typecast to numeric etc.

IMHO - strict types are putting extra burden to a developer who has to extra pay attention to all incoming types - which may be hard especially for user inputs. Nice example why over-strictyping in PHP is becoming contra-productive.

samdark · June 12, 2020, 7:47am

@lubosdz it is true for this use-case but strict types are really helpful in all layers not connected with user input.

Thoulah · June 12, 2020, 11:46am

This is not connected to any user input. That why it is weird to me to have to run a validator to get it working.