Yii2 - Integrity constraint violation – yii\db\IntegrityException - mysql

Question

I have a rather weired error on trying to add data to my database. It keeps telling me that there is an Integrity violation, i.e.
SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (`ticketing_system`.`parcels`, CONSTRAINT `FK_parcels_customers_customer_id` FOREIGN KEY (`sender_id`) REFERENCES `customers` (`customer_id`))
The SQL being executed was: INSERT INTO `parcels` (`parcel_id`) VALUES (DEFAULT)
I have checked the values being inserted and all of them are picked from the referenced table. Funny bit is that when I echo the values and use them to update the database directly via SQL query on the PHPMyAdmin, the database is populated well without any problem. Again, when I try to change the order of the foreign keys as they appear on the SQL query being performed, the first one fails, meaning all the foreign keys of the model are failing.
EDITED
Here is my actionCreate in the ParcelsController
public function actionCreate()
{
$model = new Parcels();
$customerModel = new Customers();
//checking whether we are getting the logged in user id value
Yii::info("User id=".Yii::$app->user->id);
$model->received_by_id = Yii::$app->user->id;
if (Yii::$app->request->post()) {
$data = Yii::$app->request->post('Customers');
$sender_id = Customers::create([
'name' => $data['name'],
'mobile_number' => $data['mobile_number'],
'sex' => $data['sex'],
'address' => $data['address'],
'registered_by_id' => $model->received_by_id,
]);
$data = Yii::$app->request->post('Parcels');
$receiver_id = Customers::create([
'name' => $data['name'],
'mobile_number' => $data['mobile_number'],
'sex' => $data['sex'],
'address' => $data['address'],
'registered_by_id' => $model->received_by_id,
]);
$model->consignment_number = $model->generateUniqueRandomString("consignment_number");
$model->source_id = $model->receivedBy->station_id;
$model->parcel_id = Parcels::create([
'consignment_number' => $model->consignment_number,
'sender_id' => $sender_id,
'receiver_id' => $receiver_id,
'source_id' => $model->source_id,
'destination_id' => $data['destination_id'],
'type_id' => $data['type_id'],
'weight' => $data['weight'],
'cost' => $data['cost'],
'parcel_info' => $data['parcel_info'],
'received_by_id' => $model->received_by_id,
]);
// return $this->redirect(['view', 'id' => $model->parcel_id]);
} else {
return $this->render('create', [
'model' => $model, 'customerModel' => $customerModel,
]);
}
}
Customers::create function in the Customers Model
public static function create($data)
{
$model = new self;
$mobile_number = $data['mobile_number'];
$exists = $model->find()->where( [ 'mobile_number' => $mobile_number ] )->exists();
if($exists) {
$existing_customer = Customers::find()
->where('mobile_number = :mobile_number', [':mobile_number' => $mobile_number])
->one();
return $existing_customer['customer_id'];
}
else {
$model->name = $data['name'];
$model->registered_by_id = $data['registered_by_id'];
$model->mobile_number = $data['mobile_number'];
$model->sex = $data['sex'];
$model->address = $data['address'];
$model->status = 10;
$model->save();
return $model->getPrimaryKey();
}
}
Parcels::create function in the Parcels Model
public static function create($data)
{
$model = new self;
$consignment_number = $data['consignment_number'];
$receiver_id = $data['receiver_id'];
$sender_id = $data['sender_id'];
$source_id = $data['source_id'];
$destination_id = $data['destination_id'];
$type_id = $data['type_id'];
$weight = $data['weight'];
$cost = $data['cost'];
$parcel_info = $data['parcel_info'];
$received_by_id = $data['received_by_id'];
$model->save(false);
return $model->getPrimaryKey();
// echo var_dump($data);
// echo "Consignment Number: ".$consignment_number." - Sender: ".$sender_id." - Receiver: ".$receiver_id." - From: ".$source_id." - To: ".$destination_id." - Type: ".$type_id." - Weight: ".$weight." - Cost: ".$cost." - Parcel Info: ".$parcel_info." - Received By: ".$received_by_id;
}
And here is the function generateUniqueRandomString() in the Parcels Model
public function generateUniqueRandomString($attribute, $length = 10) {
$randomString = Yii::$app->getSecurity()->generateRandomString($length);
$randomString = strtoupper($randomString);
if(!$this->findOne([$attribute => $randomString]))
return $randomString;
else
return $this->generateUniqueRandomString($attribute, $length);
}

Answer 1

Sorry for bothering you guys. I was able to get the problem of where I was going wrong. In the create() function of the Parcels Model, I only created new variables and failed to bind them to the model, i.e.
$consignment_number = $data['consignment_number'];
$receiver_id = $data['receiver_id'];
$sender_id = $data['sender_id'];
$source_id = $data['source_id'];
$destination_id = $data['destination_id'];
$type_id = $data['type_id'];
$weight = $data['weight'];
$cost = $data['cost'];
$parcel_info = $data['parcel_info'];
$received_by_id = $data['received_by_id'];
Should have been:
$model->consignment_number = $data['consignment_number'];
$model->weight = $data['weight'];
$model->cost = $data['cost'];
$model->parcel_info = $data['parcel_info'];
$model->received_by_id = $data['received_by_id'];
$model->status = $data['status'];
$model->receiver_id = $data['receiver_id'];
$model->sender_id = $data['sender_id'];
$model->source_id = $data['source_id'];
$model->destination_id = $data['destination_id'];
$model->type_id = $data['type_id'];
Sorry for taking your time because of my carelessness.