Saving with HABTM in CakePHP - php

I am creating multiple associations in one go and there are a few problems when it comes to saving.
I have the following code:
<?php
foreach($userData as $user) {
$data = array('User' => array('id' => $user['id']), 'Site' => array('id' => $user['site_id']));
$this->User->save($data);
}
?>
I have experimented with formatting the data array in different ways although I always encounter the same problems. Either the previous entries get moved when a new one is inserted or the current one gets updated.
I could just use the following although I need a behavior to trigger.
$this->User->SiteUser->save($data);
Edit: Also $this->User->create(); doesn't seem to do much.

The IRC helped work out what was wrong, once the unique key was set to false everything was able to save correctly.
//In the user model
var $hasAndBelongsToMany = array(
'Site' => array(
'className' => 'Site',
'unique' => false
)
);

Try resetting the id before a new save(), possibly on both models:
$this->User->id = null;
Cake decides whether to update or insert entries based on the set id, and save() sets an id automatically. Not sure why create() doesn't take care of this for you.
Also, if you want to save HABTM data, you should need to use saveAll() instead of save(). Also see this question.

Related

How to simplify this Laravel PHP code to one Eloquent query?

I assume that this should all be in one query in order to prevent duplicate data in the database. Is this correct?
How do I simplify this code into one Eloquent query?
$user = User::where( 'id', '=', $otherID )->first();
if( $user != null )
{
if( $user->requestReceived() )
accept_friend( $otherID );
else if( !$user->requestSent() )
{
$friend = new Friend;
$friend->user_1= $myID;
$friend->user_2 = $otherID;
$friend->accepted = 0;
$friend->save();
}
}
I assume that this should all be in one query in order to prevent
duplicate data in the database. Is this correct?
It's not correct. You prevent duplication by placing unique constraints on database level.
There's literally nothing you can do in php or any other language for that matter, that will prevent duplicates, if you don't have unique keys on your table(s). That's a simple fact, and if anyone tells you anything different - that person is blatantly wrong. I can explain why, but the explanation would be a lengthy one so I'll skip it.
Your code should be quite simple - just insert the data. Since it's not exactly clear how uniqueness is handled (it appears to be user_2, accepted, but there's an edge case), without a bit more data form you - it's not possible to suggest a complete solution.
You can always disregard what I wrote and try to go with suggested solutions, but they will fail miserably and you'll end up with duplicates.
I would say if there is a relationship between User and Friend you can simply employ Laravel's model relationship, such as:
$status = User::find($id)->friends()->updateOrCreate(['user_id' => $id], $attributes_to_update));
Thats what I would do to ensure that the new data is updated or a new one is created.
PS: I have used updateOrCreate() on Laravel 5.2.* only. And also it would be nice to actually do some check on user existence before updating else some errors might be thrown for null.
UPDATE
I'm not sure what to do. Could you explain a bit more what I should do? What about $attributes_to_update ?
Okay. Depending on what fields in the friends table marks the two friends, now using your example user_1 and user_2. By the example I gave, the $attributes_to_update would be (assuming otherID is the new friend's id):
$attributes_to_update = ['user_2' => otherID, 'accepted' => 0 ];
If your relationship between User and Friend is set properly, then the user_1 would already included in the insertion.
Furthermore,on this updateOrCreate function:
updateOrCreate($attributes_to_check, $attributes_to_update);
$attributes_to_check would mean those fields you want to check if they already exists before you create/update new one so if I want to ensure, the check is made when accepted is 0 then I can pass both say `['user_1' => 1, 'accepted' => 0]
Hope this is clearer now.
I'm assuming "friends" here represents a many-to-many relation between users. Apparently friend requests from one user (myID) to another (otherId).
You can represent that with Eloquent as:
class User extends Model
{
//...
public function friends()
{
return $this->belongsToMany(User::class, 'friends', 'myId', 'otherId')->withPivot('accepted');
}
}
That is, no need for Friend model.
Then, I think this is equivalent to what you want to accomplish (if not, please update with clarification):
$me = User::find($myId);
$me->friends()->syncWithoutDetaching([$otherId => ['accepted' => 0]]);
(accepted 0 or 1, according to your business logic).
This sync method prevents duplicate inserts, and updates or creates any row for the given pair of "myId - otherId". You can set any number of additional fields in the pivot table with this method.
However, I agree with #Mjh about setting unique constraints at database level as well.
For this kind of issue, First of all, you have to enjoy the code and database if you are working in laravel. For this first you create realtionship between both table friend and user in database as well as in Models . Also you have to use unique in database .
$data= array('accepted' => 0);
User::find($otherID)->friends()->updateOrCreate(['user_id', $otherID], $data));
This is query you can work with this . Also you can pass multiple condition here. Thanks
You can use firstOrCreate/ firstOrNew methods (https://laravel.com/docs/5.3/eloquent)
Example (from docs) :
// Retrieve the flight by the attributes, or create it if it doesn't exist...
$flight = App\Flight::firstOrCreate(['name' => 'Flight 10']);
// Retrieve the flight by the attributes, or instantiate a new instance...
$flight = App\Flight::firstOrNew(['name' => 'Flight 10']);
use `firstOrCreate' it will do same as you did manually.
Definition of FirstOrCreate copied from the Laravel Manual.
The firstOrCreate method will attempt to locate a database record using the given column / value pairs. If the model can not be found in the database, a record will be inserted with the given attributes.
So according to that you should try :
$user = User::where( 'id', '=', $otherID )->first();
$friend=Friend::firstOrCreate(['user_id' => $myId], ['user_2' => $otherId]);
It will check with both IDs if not exists then create record in friends table.

Manually packaging data for CakePHP's save()

I'm trying to package up some data for the save() function in cakephp. I'm new to PHP, so I'm confused about how to actually write the below in code:
Array
(
[ModelName] => Array
(
[fieldname1] => 'value'
[fieldname2] => 'value'
)
)
Thank you!
To answer your question, you can create the array structure you need, and save it, by doing this:
<?php
$data = array(
'ModelName' => array(
'fieldname1' => 'value',
'fieldname2' => 'value'
)
);
$this->ModelName->save($data);
?>
Please note:
Based on what you've written above in your comments it looks like you're not keeping to the CakePHP conventions. It's possible to do things this way but you'll save yourself a lot of time and trouble if you decided to stick with the CakePHP defaults as much as possible, and only do it your own way when you have a good reason to.
A couple things to remember are:
Model names should be singular. This means that your model should be called Follower instead of Followers.
The model's primary key in the database should be named just id, not followers_id, and should be set as PRIMARY KEY and AUTO_INCREMENT in your database.
If you decide not to follow the conventions you'll probably find yourself scratching your head, wondering why things aren't working, every step of the way. Try having a look at the CakePHP documentation for more details.
I think you need to do like below:
$this->Followers->create();
$this->data['Followers']['user_id'] = $user_id;
$this->data['Followers']['follower_id'] = $follower_id; // If it is primary and auto increment than you don't need this line.
$this->Followers->save($this->data)

Is there a way to make saveAll() remove extraneous objects?

My host object hasMany option objects associated with it. In the edit form, users can (de)select options and save that new set of associations. This is implemented using saveAll() on the posted data. The result is that
the host (main) object is updated,
option (associated) objects that are included both in the prior and the new association are updated, and
option objects that were not included in the prior association but are included in the new one are created.
But what does not happen is
that option objects that were included in the prior association but not in the new one are deleted.
Question: Can saveAll() do that as well, and how would the data structure have to look like to achieve this effect?
Related information:
My code to handle the edit form is actually more complex (hence I haven't quoted it here) but it results in the data structure as described in the book:
( [Host] => ( ... host object fields ... ),
[Option] => ( [0] => ( ... first option object fields ... ),
...
[n] => ( ... nth option object fields ... )
)
)
Now, if the original host had an associated option that is not included in the 0..n array then saveAll() won't detect this and won't delete that associated object.
Not sure if this is relevant but I am using CakePHP 1.3 .
Not really an elegant solution but works for me.
if ($this->Main->saveAll($this->data))
{
$this->Main->query(sprintf(
'DELETE '
. 'FROM extraneous '
. 'WHERE main_id = \'%s\' AND modified < (SELECT modified FROM main WHERE id = \'%1$s\')'
, mysql_real_escape_string($this->Main->id)
));
}
Note that your tables need to have a modified field.
You can ensure that everything gets executed atomically if you manually wrap everything into a transaction.
This can be done with the begin(), rollback() and commit() methods of the datasource:
$this->Main->begin();
if ( !$this->Main->save(...) ) {
$this->Main->rollback();
return false;
}
// Perform saves in related models...
if ( !$this->Main->MainRelatedModel->save(...) ) {
$this->Main->rollback();
return false;
}
// Perform deletes in extraneous records...
if ( !$this->Main->MainRelatedModel->delete(...) ) {
$this->Main->rollback();
return false;
}
// Everything went well, commit and close the transaction
$this->Main->commit();
The main disadvantage here is that transactions cannot be nested, hence you cannot use saveAll(). You have to save/delete everything step by step, instead of doing it in a single call.
saveAll() wont delete anything from your database.
I guess the best way is to delete options related to the current host before saving, and then adding them. If however, you need to update those that already exists (do you?) for some reason (like: options being related to some other models), I guess you can try to write a piece of code, that will delete unselected options.
Looking for this, I noticed there still isn't a solution built-in CakePHP. To achieve this, I added the following code to my model:
private $oldBarIds = array();
public function beforeSave($options = array() {
parent::beforeSave($options);
$this->oldBarIds = array();
if ($this->id && $this->exists() && isset($this->data['Bar'])) {
$oldBars = $this->Bar->find('all', array(
'fields' => array('id'),
'conditions' => array(
'Bar.foo_id' => $this->id
)
));
$this->oldBarIds = Hash::extract($oldBars, '{n}.id');
}
}
This checks if Bar exists in the saving data. If it does, it'll get the current id's of the current ones, setting them to $this->oldBarIds. Then when the save succeeds, it should delete the old ones:
public function afterSave($created, $options = array()) {
parent::afterSave($created, $options);
if (!$created && $this->oldBarIds) {
$this->Bar->deleteAll(array(
'Bar' => $this->oldBarIds
));
}
}
This way the deletion is handled by the model, and only occurs when the save succeeded. Should be able to add this to a behavior, might do this some day.
HABTM deletes all associated records then recreates what is needed. As PawelMysior suggests, you could achieve this with your hasMany by manually deleting the associated records immediately before the save. The danger, though, is that the save fails you lose the previous state.
I would go with a variant of GJ's solution and delete them after a successful save, but instead loop over an array of redundant IDs and use Cake's Model->del() method. This way you retain all the built-in error handling.

CakePHP HABTM Filtering

I've got two tables - users and servers, and for the HABTM relationship, users_servers. Users HABTM servers and vice versa.
I'm trying to find a way for Cake to select the servers that a user is assigned to.
I'm trying things like $this->User->Server->find('all'); which just returns all the servers, regardless of whether they belong to the user.
$this->User->Server->find('all', array('conditions' => array('Server.user_id' => 1))) just gives an unknown column SQL error.
I'm sure I'm missing something obvious but just need someone to point me in the right direction.
Thanks!
Your table names are right. There are many ways to do this:
Use the Containable behavior
In your AppModel, set the following:
var $recursive = -1;
var $actsAs = array('Containable');
Then, use the following code to query your servers:
$userWithServers = $this->User->find('all', array(
'conditions' => array('User.id' => 1),
'contain' => array('Server')
));
Note that we are querying the User model, instead of the Server model to accomplish this.
Use bindModel
$this->Server->bindModel(array('hasOne' => array('UsersServer')));
$this->Server->find('all', array(
'fields' => array('Server.*'),
'conditions' => array('Server.user_id' => 1)
));
I personally don't recommend using bindModel a lot. Eventually, your code becomes a bit unmanagable. You should try using the Containable behavior whenever possible. The code looks cleaner and simpler. More on the bindModel method can be found here.
HTH.
I think you're supposed to name tour table user_servers.

adding hasMany association causes find() to not work well

OK, I am a little bit lost...
I am pretty new to PHP, and I am trying to use CakePHP for my web-site.
My DB is composed of two tables:
users with user_id, name columns
copies with copy_id, copy_name, user_id (as foreign key to users) columns.
and I have the matching CakePHP elements:
User and Copy as a model
UserController as controller
I don't use a view since I just send the json from the controller.
I have added hasMany relation between the user model and the copy model see below.
var $hasMany = array(
'Copy' => array(
'className' => 'Friendship',
'foreignKey' => 'user_id'
)
);
Without the association every find() query on the users table works well, but after adding the hasMany to the model, the same find() queries on the users stop working (print_r doesn't show anything), and every find() query I am applying on the Copy model
$copy = $this->User->Copy->find('all', array(
'condition' => array('Copy.user_id' => '2')
));
ignores the condition part and just return the whole data base.
How can I debug the code execution? When I add debug($var) nothing happens.
I'm not an expert, but you can start with the following tips:
Try to follow the CakePHP database naming conventions. You don't have to, but it's so much easier to let the automagic happen... Change the primary keys in your tabel to 'id', e.g. users.user_is --> users.id, copies.copy_id -->copies.id.
Define a view, just for the sake of debugging. Pass whatever info from model to view with $this->set('users', $users); and display that in a <pre></pre> block
If this is your first php and/or CakePHP attempt, make sure you do at least the blog tutorial
Make CakePHP generate (bake) a working set of model/view/controllers for users and copies and examine the resulting code
There's good documentation about find: the multifunctional workhorseof all model data-retrieval functions
I think the main problem is this:
'condition' => array('Copy.user_id' => '2')
It should be "conditions".
Also, stick to the naming conventions. Thankfully Cake lets you override pretty much all its assumed names, but it's easier to just do what they expect by default.
The primary keys should be all named id
The controller should be pluralised: UsersController
First off, try as much as possible to follow CakePHP convention.
var $hasMany = array(
'Copy' => array(
'className' => 'Friendship',
'foreignKey' => 'user_id'
)
);
Your association name is 'Copy' which is a different table and model then on your classname, you have 'Friendship'.
Why not
var $hasMany = array(
'Copy' => array('className'=>'Copy')
);
or
var $hasMany = array(
'Friendship' => array('className'=>'Friendship')
);
or
var $hasMany = array(
'Copy' => array('className'=>'Copy'),
'Friendship' => array('className'=>'Friendship')
);
Also, check typo errors like conditions instead of condition
Your table name might be the problem too. I had a table named "Class" and that gave cake fits. I changed it to something like Myclass and it worked. Class was a reserved word and Copy might be one too.

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