Problem with Polymorphic Relationships in Laravel - php

I'm trying to implement a way to get the details of a person depending on the group it belongs to.
My database looks like this:
persons:
id
group
type
1
person
9
2
company
30
3
person
9
and so on.
Each "group" has a model which contains detail information for this record specific to the group.
For example:
persondetails looks like this
id
person_id
firstname
lastname
birthname
1
1
Harry
Example
Bornas
2
3
Henrietta
Example
Bornas
I created models for each table and I'm no trying to implement a relationship which allows me to query a person->with('details') via the person model (for example: for a complete list of all persons no matter which type it is).
For single records I got it working via a simple "if $this->group === person {$this->hasOne()}" relation, which doesn't work for listings.
I tried to wrap my head around a way to use a polymorphic relationship, so I put the following into the person model:
public function details(){
Relation::morphMap([
'person' => 'App\Models\Persondetail',
'company' => 'App\Models\Companydetail',
]);
return $this->morphTo();
}
and a subsequent
public function person(){
return $this->morphMany(Person::class, 'details');
}
which doesn't work sadly. Where is my thinking error?

As you're not using laravel convention for the keys, you need to define the keys on your relation
public function details()
{
Relation::morphMap([
'person' => 'App\Models\Persondetail',
'company' => 'App\Models\Companydetail',
]);
return $this->morphTo(__FUNCTION__, 'group', 'type');
}
Docs Link:
https://laravel.com/docs/9.x/eloquent-relationships#morph-one-to-one-key-conventions

Based on the reply by https://stackoverflow.com/users/8158202/akhzar-javed I figure it out, but I had to change the code a bit:
Instead of the code in the answer, I had to use the following:
public function details()
{
Relation::morphMap([
'person' => 'App\Models\Persondetails',
'company' => 'App\Models\Companydetail',
]);
return $this->morphTo(__FUNCTION__, 'group', 'id', 'person_id');
}

Related

OctoberCMS filter Relation Widget based from currently selected record

The title says it all, but to give an example. I have a Member record and a Group. A member can have memberships in many groups and a group can have many members. (So that's many to many and I would have a pivot table for it.)
Now, each group has membership grades. E.g., (Free, Freemium, Premium, Super Premium). So the membership_grade shall belong to the pivot table, right? But here's the problem, not all groups share the same grades. Some might have Free and Freemium only, some might have all.
In the fields.yaml of the Membership pivot model, I defined the membership_grades as a Relation Widget, like this:
pivot[grade]:
label: Membership Grade
span: full
type: relation
nameFrom: name
And in its relationship in Membership.php like this:
public $belongsTo = [
'grade' => [
'Acme\Models\Grade',
]
];
Obviously, this will expose ALL grades, since I'm pulling data from the Grade model. What I want is to expose the grades that is just available on that group, not all.
What I've thought to do (but I didn't, because it seemed impossible) is to try to pull data from the grades relationship of the Group, but how am I suppose to do that? (Since Relation widget manages the relation of the Model, I cannot simply pull data from other sources just like that).
Also I've tried to do scopes but how am I suppose to pass the current Group I'm in? Since it is needed as the filter, like this:
// Membership.php
public $belongsTo = [
'grade' => [
'Acme\Models\Grade',
'scope' => 'filteredIt'
],
// added this relationship to try the scopes approach
'group' => [
'Acme\Models\Group'
]
];
// Grade.php
public function scopeFilteredIt($query, Membership $m)
// yes, the second parameter in the scope will be the
// current Membership model. I've tried it.
{
// this won't work, since we want the overall relation filter;
// an instance of Membership won't help.
// this would work if I can find a way to pass the
// current Group (record) selected, and get its grades, then use it here.
return $query->whereIn('id', $m->group->grades->pluck('id')->all());
}
Any thoughts?
I have noticed some post values during pivot model ajax call.
When you add new record and when your pivot model opens post values are like this
Array (
[_relation_field] => groups
[_relation_extra_config] => W10=
[foreign_id] => 1
[_session_key] => VrSCoKQrSkIsZNGIju5QIqpdbS3AADoGQRHAsv1e
)
So good thing is that we can now get foreign_id as it will be your selected group id
and we can use it at creation time and for update time you know we have relation so we use that.
public function scopefilteredIt($query, Membership $m)
{
// we are checking relation is there or not
if($m->group) {
// yes group is there we use it
return $query->whereIn('id', $m->group->grades->pluck('id')->all());
}
else {
// seems new record then use foreign_id
$foreign_id = post('foreign_id'); //<-this will be your selected group id
if($foreign_id) { // <- double check if its there
$group = Group::find($foreign_id);
return $query->whereIn('id', $group->grades->pluck('id')->all());
}
}
return $query;
}
please comment if you get any issue.
to check post
public function scopefilteredIt($query, Membership $m)
{
// will show flash message with post data array
$post = print_r(post(), true);
\Flash::success($post);
// we are checking relation is there or not
if($m->group) {
// yes group is there we use it
return $query->whereIn('id', $m->group->grades->pluck('id')->all());
}
else {
// seems new record then use foreign_id
$foreign_id = post('foreign_id'); //<-this will be your selected group id
if($foreign_id) { // <- double check if its there
$group = Group::find($foreign_id);
return $query->whereIn('id', $group->grades->pluck('id')->all());
}
}
return $query;
}

Display attribute using via() or viaTable() when there is multiple relations- YII2

I have for models say, supplier-machine, supplier, supplier-to-part and parts.
This is how these tables are related to each other.
In Supplier model the relation is defined as below to retrieve part_name of Part table keeping supplier-to-part as junction table.
public function getSupplierToParts()
{
return $this->hasMany(SupplierToPart::className(), ['supplier_id' => 'id']);
}
public function getParts()
{
return $this->hasMany(Part::className(), ['id' => 'part_id'])->viaTable('supplier_to_part', ['supplier_id' => 'id']);
}
In Detail view I use implode to display part_name
[
'attribute'=>'Nature of business',
'value' => implode(\yii\helpers\ArrayHelper::map($model->parts, 'id', 'part_name')),
],
My question is how do I display part_name in supplier-machine model instead of supplier model?? In this case I think supplier and supplier-to-part becomes like a two junction tables. How do I solve this?
You can access the parts through the supplier relation via $model->supplier->parts, assuming your relation to Supplier in your SupplierMachine model is supplier. You still have to account for the multiple parts though:
'value' => implode(",",
\yii\helpers\ArrayHelper::map($model->supplier->parts, 'id', 'part_name')
),

Cakephp 3: Set virtual property with condition on belongsToMany association

I have two tables, Tickets and Paintings. A ticket can have many paintings and a painting can be used on many tickets. They have a join table called tickets_paintings with ticket_id and painting_id. Here's how the tables are set:
class TicketsTable extends Table
{
public function initialize(array $config)
{
$this->belongsToMany('Paintings', [
'foreignKey' => 'ticket_id',
'targetForeignKey' => 'painting_id',
'joinTable' => 'tickets_paintings'
]);
}
class PaintingsTable extends Table
{
public function initialize(array $config)
{
$this->belongsToMany('Tickets', [
'foreignKey' => 'painting_id',
'targetForeignKey' => 'ticket_id',
'joinTable' => 'tickets_paintings'
]);
}
Every Ticket has a field "active" that is boolean and tells me if the ticket is currently in use or not. In the edit function the field can be changed to true or false.
But now I also need a property for every Painting, that tells me if this painting is currently used on an active ticket. In this case it would be unavailable to be used on another ticket.
I thought I could add a boolean virtual property for a painting, that checks if it is (currently) associated with any ticket that has active => true and is therefore also set true or false.
Like: "Does this painting belong to a ticket with state active => 0".
And then set the virtual property accordingly, so I can display it in a view.
I managed to create a virtual property for a painting that checks if there is an entry for its ID inside the join table so far:
class Painting extends Entity
{
protected function _getIsAvailable(){
$TicketsTable = TableRegistry::get('TicketsPaintings');
$exists = $TicketsTable->exists(['painting_id' => $this->id]);
if($exists == true){
return 1;
} else {
return 0;
}
}
}
A) How could I add a condition that checks if any matching ticket_id in the join table has an active=> 1 in the original Tickets table?
The query would have to check the ticket_id in the join table in an DESC order and return true as soon as the first active ticket is found (so it does not check the whole thing every time)
I don't even understand how to access that "active" property on the tickets table to check it. I assume I would have to use the " has Many through" option?! But even trying to following the explanation in the book and this question exactly (for hours), I am not able to get this to work for my example because I don't understand the correct syntax I had to use for my tables.
B) Is it even possible or "advisable" to check sth like this inside the Entity?
I tried to use an extra db field in the paintings table first but it seemed much more complicated to check and set another value every time a ticket is edited (not that I managed to make that work either)...and the active value is pretty much doubled then for ticket and painting. So I thought the virtual property would be easier to handle. Or am I on the completely wrong train?
Thanks for any tips or advice on this nightmare =)!
Since nobody came to my rescue I managed to put something together and actually create the virtual property I wanted. I don't know if this is the best way to go but it works for me and I will put it here in case anyone is searching for similar case.
I created a finder method inside the Paintings Table that joins the 3 tables and filters out all paintings that are connected to an active ticket.
class PaintingsTable extends Table
{
public function findNotavailable(Query $query, array $options){
$query
->join([
'tickets_paintings' =>[
'table' => 'tickets_paintings',
'type' => 'LEFT',
'conditions' => 'tickets_paintings.painting_id = Paintings.id'
],
'tickets' => [
'table' => 'tickets',
'type' => 'LEFT',
'conditions' => 'tickets_paintings.ticket_id = Tickets.id'
],
])
->select(['Paintings.id'])
->order(['tickets_paintings.ticket_id' => 'DESC'])
->where([
'Tickets.active' => false
]);
return $query;
}
}
Then in the Entity of the Painting I check if its ID is inside this selection and set a boolean virtual property accordingly:
use Cake\ORM\TableRegistry;
class Painting extends Entity
{
protected function _getNotAvailable(){
$Paintings = TableRegistry::get('Paintings');
$notavailable = $Paintings->find('notavailable')
->where(['Paintings.id'=>$this->id]);
if($notavailable->isEmpty()){
// if no record --> painting is available
return 0;
} else {
// if record found --> painting is not available
return 1;
}
}
}
And in the view I display it like this:
In Paintings - view.ctp
<?= $painting->not_available ? __('not available') : __('available'); ?>
The only downside to it is that virtual properties can't be used for pagination as far as I understand the book. But I'm sure there's a workaround for that too.

Gii CRUD in Yii2 Generating Junction Table Relations

I have three models: Person, Feature and PersonFeature. PersonFeature is a junction table with two foreign keys, person_id referencing id in the person table and feature_id referencing id in the feature table.
My question is does Gii in Yii2 generate all the relevant relations. These are the relation in each of the three models
Person:
public function getPersonfeatures()
{
return $this->hasMany(Personfeature::className(), ['personid' => 'id']);
}
Feature:
public function getPersonfeatures()
{
return $this->hasMany(Personfeature::className(), ['featureid' => 'id']);
}
PersonFeature:
public function getPerson()
{
return $this->hasOne(Person::className(), ['id' => 'personid']);
}
public function getFeature()
{
return $this->hasOne(Feature::className(), ['id' => 'featureid']);
}
But when I browse other posts I see that there exists a 'viaTable' operation for example:
public function getPerson() {
return $this->hasMany(Person::className(), ['id' => 'personid'])
->viaTable('personfeature', ['featureid' => 'id']);}
So basically my question is, is Yii supposed to generate this for me? Or can I manually add it in?
Cheers
The last function (with viaTable) is a many to many relationship, that function can be used just as any other relational function (for instance in a ->with() query).
You don't need a model for your join table, unless you want to use it for something else.
Hope this helps.

Retrieve data from junction table in Yii2

I'm trying to get data from a join table in Yii2 without an additional query. I have 2 models (User, Group) associated via the junction table (user_group). In the user_group table, I want to store extra data (admin flag, ...) for this relation.
What's the best way to add data to the junction table? The link method accepts a parameter extraColumns but I can't figure out how this works.
What's the best way to retrieve this data? I wrote an additional query to get the values out of the junction table. There must be a cleaner way to do this?!
FYI, this is how I defined the relation in the models:
Group.php
public function getUsers() {
return $this->hasMany(User::className(), ['id' => 'user_id'])
->viaTable('user_group', ['group_id' => 'id']);
}
User.php
public function getGroups() {
return $this->hasMany(Group::className(), ['id' => 'group_id'])
->viaTable('user_group', ['user_id' => 'id']);
}
In short: Using an ActiveRecord for the junction table like you suggested is IMHO the right way because you can set up via() to use that existing ActiveRecord. This allows you to use Yii's link() method to create items in the junction table while adding data (like your admin flag) at the same time.
The official Yii Guide 2.0 states two ways of using a junction table: using viaTable() and using via() (see here). While the former expects the name of the junction table as parameter the latter expects a relation name as parameter.
If you need access to the data inside the junction table I would use an ActiveRecord for the junction table as you suggested and use via():
class User extends ActiveRecord
{
public function getUserGroups() {
// one-to-many
return $this->hasMany(UserGroup::className(), ['user_id' => 'id']);
}
}
class Group extends ActiveRecord
{
public function getUserGroups() {
// one-to-many
return $this->hasMany(UserGroup::className(), ['group_id' => 'id']);
}
public function getUsers()
{
// many-to-many: uses userGroups relation above which uses an ActiveRecord class
return $this->hasMany(User::className(), ['id' => 'user_id'])
->via('userGroups');
}
}
class UserGroup extends ActiveRecord
{
public function getUser() {
// one-to-one
return $this->hasOne(User::className(), ['id' => 'user_id']);
}
public function getGroup() {
// one-to-one
return $this->hasOne(Group::className(), ['id' => 'userh_id']);
}
}
This way you can get the data of the junction table without additional queries using the userGroups relation (like with any other one-to-many relation):
$group = Group::find()->where(['id' => $id])->with('userGroups.user')->one();
// --> 3 queries: find group, find user_group, find user
// $group->userGroups contains data of the junction table, for example:
$isAdmin = $group->userGroups[0]->adminFlag
// and the user is also fetched:
$userName = $group->userGroups[0]->user->name
This all can be done using the hasMany relation. So you may ask why you should declare the many-to-many relation using via(): Because you can use Yii's link() method to create items in the junction table:
$userGroup = new UserGroup();
// load data from form into $userGroup and validate
if ($userGroup->load(Yii::$app->request->post()) && $userGroup->validate()) {
// all data in $userGroup is valid
// --> create item in junction table incl. additional data
$group->link('users', $user, $userGroup->getDirtyAttributes())
}
I don't know for sure it is best solution. But for my project it will be good for now :)
1) Left join
Add new class attribute in User model public $flag;.
Append two lines to your basic relation but don't remove viaTable this can (and should) stay.
public function getUsers()
{
return $this->hasMany(User::className(), ['id' => 'user_id'])
->viaTable('user_group', ['group_id' => 'id'])
->leftJoin('user_group', '{{user}}.id=user_id')
->select('{{user}}.*, flag') //or all ->select('*');
}
leftJoin makes possible to select data from junction table and with select to customize your return columns.
Remember that viaTable must stay because link() relies on it.
2) sub-select query
Add new class attribute in User model public $flag;
And in Group model modified getUsers() relation:
public function getUsers()
{
return $this->hasMany(User::className(), ['id' => 'user_id'])
->viaTable('user_group', ['group_id' => 'id'])
->select('*, (SELECT flag FROM user_group WHERE group_id='.$this->id.' AND user_id=user.id LIMIT 1) as flag');
}
As you can see i added sub-select for default select list. This select is for users not group model. Yes, i agree this is litle bit ugly but does the job.
3) Condition relations
Different option is to create one more relation for admins only:
// Select all users
public function getUsers() { .. }
// Select only admins (users with specific flag )
public function getAdmins()
{
return $this->hasMany(User::className(), ['id' => 'user_id'])
->viaTable('user_group', ['group_id' => 'id'],
function($q){
return $q->andWhere([ 'flag' => 'ADMIN' ]);
});
}
$Group->admins - get users with specific admin flag. But this solution doesn't add attribute $flag. You need to know when you select only admins and when all users. Downside: you need to create separate relation for every flag value.
Your solution with using separate model UserGroup still is more flexible and universal for all cases. Like you can add validation and basic ActiveRecord stuff. These solutions are more one way direction - to get stuff out.
Since I have received no answer for almost 14 days, I'll post how I solved this problem. This is not exactly what I had in mind but it works, that's enough for now. So... this is what I did:
Added a model UserGroup for the junction table
Added a relation to Group
public function getUserGroups()
{
return $this->hasMany(UserGroup::className(), ['user_id' => 'id']);
}
Joined UserGroup in my search model function
$query = Group::find()->where('id =' . $id)->with('users')->with('userGroups');
This get's me what I wanted, the Group with all Users and, represented by my new model UserGroup, the data from the junction table.
I thought about extending the query building Yii2 function first - this might be a better way to solve this. But since I don't know Yii2 very well yet, I decided not to do for now.
Please let me know if you have a better solution.
For that purpose I've created a simple extension, that allows to attach columns in junction table to child model in relation as properties.
So after setting up this extension you will be able to access junction table attributes like
foreach ($parentModel->relatedModels as $childModel)
{
$childModel->junction_table_column1;
$childModel->junction_table_column2;
....
}
For more info please have look at
Yii2 junction table attributes extension
Thanks.

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